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Standard Ed. 7

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java.util

Class Collections

java.lang.Object

java.util.Collections

public class Collections
extends Object

This class consists exclusively of static methods that operate on or return
 collections.  It contains polymorphic algorithms that operate on
 collections, "wrappers", which return a new collection backed by a
 specified collection, and a few other odds and ends.

The methods of this class all throw a <tt>NullPointerException</tt>
 if the collections or class objects provided to them are null.

The documentation for the polymorphic algorithms contained in this class
 generally includes a brief description of the implementation.  Such
 descriptions should be regarded as implementation notes, rather than
 parts of the specification.  Implementors should feel free to
 substitute other algorithms, so long as the specification itself is adhered
 to.  (For example, the algorithm used by <tt>sort</tt> does not have to be
 a mergesort, but it does have to be stable.)

The "destructive" algorithms contained in this class, that is, the
 algorithms that modify the collection on which they operate, are specified
 to throw <tt>UnsupportedOperationException</tt> if the collection does not
 support the appropriate mutation primitive(s), such as the <tt>set</tt>
 method.  These algorithms may, but are not required to, throw this
 exception if an invocation would have no effect on the collection.  For
 example, invoking the <tt>sort</tt> method on an unmodifiable list that is
 already sorted may or may not throw <tt>UnsupportedOperationException</tt>.

This class is a member of the

 Java Collections Framework.

Since:

1.2

See Also:

Collection,
Set,
List,
Map

Field Summary

Fields

Modifier and Type
Field and Description

static List
EMPTY_LIST

The empty list (immutable).

static Map
EMPTY_MAP

The empty map (immutable).

static Set
EMPTY_SET

The empty set (immutable).

Method Summary

Methods

Modifier and Type
Method and Description

static <T> boolean
addAll(Collection<? super T> c,
      T... elements)

Adds all of the specified elements to the specified collection.

static <T> Queue<T>
asLifoQueue(Deque<T> deque)

Returns a view of a Deque as a Last-in-first-out (Lifo)
 Queue.

static <T> int
binarySearch(List<? extends Comparable<? super T>> list,
            T key)

Searches the specified list for the specified object using the binary
 search algorithm.

static <T> int
binarySearch(List<? extends T> list,
            T key,
            Comparator<? super T> c)

Searches the specified list for the specified object using the binary
 search algorithm.

static <E> Collection<E>
checkedCollection(Collection<E> c,
                 Class<E> type)

Returns a dynamically typesafe view of the specified collection.

static <E> List<E>
checkedList(List<E> list,
           Class<E> type)

Returns a dynamically typesafe view of the specified list.

static <K,V> Map<K,V>
checkedMap(Map<K,V> m,
          Class<K> keyType,
          Class<V> valueType)

Returns a dynamically typesafe view of the specified map.

static <E> Set<E>
checkedSet(Set<E> s,
          Class<E> type)

Returns a dynamically typesafe view of the specified set.

static <K,V> SortedMap<K,V>
checkedSortedMap(SortedMap<K,V> m,
                Class<K> keyType,
                Class<V> valueType)

Returns a dynamically typesafe view of the specified sorted map.

static <E> SortedSet<E>
checkedSortedSet(SortedSet<E> s,
                Class<E> type)

Returns a dynamically typesafe view of the specified sorted set.

static <T> void
copy(List<? super T> dest,
    List<? extends T> src)

Copies all of the elements from one list into another.

static boolean
disjoint(Collection<?> c1,
        Collection<?> c2)

Returns true if the two specified collections have no
 elements in common.

static <T> Enumeration<T>
emptyEnumeration()

Returns an enumeration that has no elements.

static <T> Iterator<T>
emptyIterator()

Returns an iterator that has no elements.

static <T> List<T>
emptyList()

Returns the empty list (immutable).

static <T> ListIterator<T>
emptyListIterator()

Returns a list iterator that has no elements.

static <K,V> Map<K,V>
emptyMap()

Returns the empty map (immutable).

static <T> Set<T>
emptySet()

Returns the empty set (immutable).

static <T> Enumeration<T>
enumeration(Collection<T> c)

Returns an enumeration over the specified collection.

static <T> void
fill(List<? super T> list,
    T obj)

Replaces all of the elements of the specified list with the specified
 element.

static int
frequency(Collection<?> c,
         Object o)

Returns the number of elements in the specified collection equal to the
 specified object.

static int
indexOfSubList(List<?> source,
              List<?> target)

Returns the starting position of the first occurrence of the specified
 target list within the specified source list, or -1 if there is no
 such occurrence.

static int
lastIndexOfSubList(List<?> source,
                  List<?> target)

Returns the starting position of the last occurrence of the specified
 target list within the specified source list, or -1 if there is no such
 occurrence.

static <T> ArrayList<T>
list(Enumeration<T> e)

Returns an array list containing the elements returned by the
 specified enumeration in the order they are returned by the
 enumeration.

static <T extends Object & Comparable<? super T>>
T
max(Collection<? extends T> coll)

Returns the maximum element of the given collection, according to the
 natural ordering of its elements.

static <T> T
max(Collection<? extends T> coll,
   Comparator<? super T> comp)

Returns the maximum element of the given collection, according to the
 order induced by the specified comparator.

static <T extends Object & Comparable<? super T>>
T
min(Collection<? extends T> coll)

Returns the minimum element of the given collection, according to the
 natural ordering of its elements.

static <T> T
min(Collection<? extends T> coll,
   Comparator<? super T> comp)

Returns the minimum element of the given collection, according to the
 order induced by the specified comparator.

static <T> List<T>
nCopies(int n,
       T o)

Returns an immutable list consisting of <tt>n</tt> copies of the
 specified object.

static <E> Set<E>
newSetFromMap(Map<E,Boolean> map)

Returns a set backed by the specified map.

static <T> boolean
replaceAll(List<T> list,
          T oldVal,
          T newVal)

Replaces all occurrences of one specified value in a list with another.

static void
reverse(List<?> list)

Reverses the order of the elements in the specified list.

static <T> Comparator<T>
reverseOrder()

Returns a comparator that imposes the reverse of the natural
 ordering on a collection of objects that implement the
 Comparable interface.

static <T> Comparator<T>
reverseOrder(Comparator<T> cmp)

Returns a comparator that imposes the reverse ordering of the specified
 comparator.

static void
rotate(List<?> list,
      int distance)

Rotates the elements in the specified list by the specified distance.

static void
shuffle(List<?> list)

Randomly permutes the specified list using a default source of
 randomness.

static void
shuffle(List<?> list,
       Random rnd)

Randomly permute the specified list using the specified source of
 randomness.

static <T> Set<T>
singleton(T o)

Returns an immutable set containing only the specified object.

static <T> List<T>
singletonList(T o)

Returns an immutable list containing only the specified object.

static <K,V> Map<K,V>
singletonMap(K key,
            V value)

Returns an immutable map, mapping only the specified key to the
 specified value.

static <T extends Comparable<? super T>>
void
sort(List<T> list)

Sorts the specified list into ascending order, according to the
 natural ordering of its elements.

static <T> void
sort(List<T> list,
    Comparator<? super T> c)

Sorts the specified list according to the order induced by the
 specified comparator.

static void
swap(List<?> list,
    int i,
    int j)

Swaps the elements at the specified positions in the specified list.

static <T> Collection<T>
synchronizedCollection(Collection<T> c)

Returns a synchronized (thread-safe) collection backed by the specified
 collection.

static <T> List<T>
synchronizedList(List<T> list)

Returns a synchronized (thread-safe) list backed by the specified
 list.

static <K,V> Map<K,V>
synchronizedMap(Map<K,V> m)

Returns a synchronized (thread-safe) map backed by the specified
 map.

static <T> Set<T>
synchronizedSet(Set<T> s)

Returns a synchronized (thread-safe) set backed by the specified
 set.

static <K,V> SortedMap<K,V>
synchronizedSortedMap(SortedMap<K,V> m)

Returns a synchronized (thread-safe) sorted map backed by the specified
 sorted map.

static <T> SortedSet<T>
synchronizedSortedSet(SortedSet<T> s)

Returns a synchronized (thread-safe) sorted set backed by the specified
 sorted set.

static <T> Collection<T>
unmodifiableCollection(Collection<? extends T> c)

Returns an unmodifiable view of the specified collection.

static <T> List<T>
unmodifiableList(List<? extends T> list)

Returns an unmodifiable view of the specified list.

static <K,V> Map<K,V>
unmodifiableMap(Map<? extends K,? extends V> m)

Returns an unmodifiable view of the specified map.

static <T> Set<T>
unmodifiableSet(Set<? extends T> s)

Returns an unmodifiable view of the specified set.

static <K,V> SortedMap<K,V>
unmodifiableSortedMap(SortedMap<K,? extends V> m)

Returns an unmodifiable view of the specified sorted map.

static <T> SortedSet<T>
unmodifiableSortedSet(SortedSet<T> s)

Returns an unmodifiable view of the specified sorted set.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

EMPTY_SET

public static final Set EMPTY_SET

The empty set (immutable).  This set is serializable.

See Also:

emptySet()

EMPTY_LIST

public static final List EMPTY_LIST

The empty list (immutable).  This list is serializable.

See Also:

emptyList()

EMPTY_MAP

public static final Map EMPTY_MAP

The empty map (immutable).  This map is serializable.

Since:

1.3

See Also:

emptyMap()

Method Detail

sort

public static <T extends Comparable<? super T>> void sort(List<T> list)

Sorts the specified list into ascending order, according to the
 natural ordering of its elements.
 All elements in the list must implement the Comparable
 interface.  Furthermore, all elements in the list must be
 mutually comparable (that is, e1.compareTo(e2)
 must not throw a ClassCastException for any elements
 e1 and e2 in the list).

This sort is guaranteed to be stable:  equal elements will
 not be reordered as a result of the sort.

The specified list must be modifiable, but need not be resizable.

Implementation note: This implementation is a stable, adaptive,
 iterative mergesort that requires far fewer than n lg(n) comparisons
 when the input array is partially sorted, while offering the
 performance of a traditional mergesort when the input array is
 randomly ordered.  If the input array is nearly sorted, the
 implementation requires approximately n comparisons.  Temporary
 storage requirements vary from a small constant for nearly sorted
 input arrays to n/2 object references for randomly ordered input
 arrays.

The implementation takes equal advantage of ascending and
 descending order in its input array, and can take advantage of
 ascending and descending order in different parts of the same
 input array.  It is well-suited to merging two or more sorted arrays:
 simply concatenate the arrays and sort the resulting array.

The implementation was adapted from Tim Peters's list sort for Python
 (
 TimSort).  It uses techiques from Peter McIlroy's "Optimistic
 Sorting and Information Theoretic Complexity", in Proceedings of the
 Fourth Annual ACM-SIAM Symposium on Discrete Algorithms, pp 467-474,
 January 1993.

This implementation dumps the specified list into an array, sorts
 the array, and iterates over the list resetting each element
 from the corresponding position in the array.  This avoids the
 n2 log(n) performance that would result from attempting
 to sort a linked list in place.

Parameters:

list - the list to be sorted.

Throws:

ClassCastException - if the list contains elements that are not
         mutually comparable (for example, strings and integers).

UnsupportedOperationException - if the specified list's
         list-iterator does not support the set operation.

IllegalArgumentException - (optional) if the implementation
         detects that the natural ordering of the list elements is
         found to violate the Comparable contract

sort

public static <T> void sort(List<T> list,
            Comparator<? super T> c)

Sorts the specified list according to the order induced by the
 specified comparator.  All elements in the list must be mutually
 comparable using the specified comparator (that is,
 c.compare(e1, e2) must not throw a ClassCastException
 for any elements e1 and e2 in the list).

This sort is guaranteed to be stable:  equal elements will
 not be reordered as a result of the sort.

The specified list must be modifiable, but need not be resizable.

Implementation note: This implementation is a stable, adaptive,
 iterative mergesort that requires far fewer than n lg(n) comparisons
 when the input array is partially sorted, while offering the
 performance of a traditional mergesort when the input array is
 randomly ordered.  If the input array is nearly sorted, the
 implementation requires approximately n comparisons.  Temporary
 storage requirements vary from a small constant for nearly sorted
 input arrays to n/2 object references for randomly ordered input
 arrays.

The implementation takes equal advantage of ascending and
 descending order in its input array, and can take advantage of
 ascending and descending order in different parts of the same
 input array.  It is well-suited to merging two or more sorted arrays:
 simply concatenate the arrays and sort the resulting array.

The implementation was adapted from Tim Peters's list sort for Python
 (
 TimSort).  It uses techiques from Peter McIlroy's "Optimistic
 Sorting and Information Theoretic Complexity", in Proceedings of the
 Fourth Annual ACM-SIAM Symposium on Discrete Algorithms, pp 467-474,
 January 1993.

This implementation dumps the specified list into an array, sorts
 the array, and iterates over the list resetting each element
 from the corresponding position in the array.  This avoids the
 n2 log(n) performance that would result from attempting
 to sort a linked list in place.

Parameters:

list - the list to be sorted.

c - the comparator to determine the order of the list.  A
        null value indicates that the elements' natural
        ordering should be used.

Throws:

ClassCastException - if the list contains elements that are not
         mutually comparable using the specified comparator.

UnsupportedOperationException - if the specified list's
         list-iterator does not support the set operation.

IllegalArgumentException - (optional) if the comparator is
         found to violate the Comparator contract

binarySearch

public static <T> int binarySearch(List<? extends Comparable<? super T>> list,
                   T key)

Searches the specified list for the specified object using the binary
 search algorithm.  The list must be sorted into ascending order
 according to the natural ordering of its
 elements (as by the sort(List) method) prior to making this
 call.  If it is not sorted, the results are undefined.  If the list
 contains multiple elements equal to the specified object, there is no
 guarantee which one will be found.

This method runs in log(n) time for a "random access" list (which
 provides near-constant-time positional access).  If the specified list
 does not implement the RandomAccess interface and is large,
 this method will do an iterator-based binary search that performs
 O(n) link traversals and O(log n) element comparisons.

Parameters:

list - the list to be searched.

key - the key to be searched for.

Returns:

the index of the search key, if it is contained in the list;
         otherwise, <tt>(-(insertion point) - 1)</tt>.  The
         insertion point is defined as the point at which the
         key would be inserted into the list: the index of the first
         element greater than the key, or <tt>list.size()</tt> if all
         elements in the list are less than the specified key.  Note
         that this guarantees that the return value will be >= 0 if
         and only if the key is found.

Throws:

ClassCastException - if the list contains elements that are not
         mutually comparable (for example, strings and
         integers), or the search key is not mutually comparable
         with the elements of the list.

binarySearch

public static <T> int binarySearch(List<? extends T> list,
                   T key,
                   Comparator<? super T> c)

Searches the specified list for the specified object using the binary
 search algorithm.  The list must be sorted into ascending order
 according to the specified comparator (as by the
 sort(List, Comparator)
 method), prior to making this call.  If it is
 not sorted, the results are undefined.  If the list contains multiple
 elements equal to the specified object, there is no guarantee which one
 will be found.

This method runs in log(n) time for a "random access" list (which
 provides near-constant-time positional access).  If the specified list
 does not implement the RandomAccess interface and is large,
 this method will do an iterator-based binary search that performs
 O(n) link traversals and O(log n) element comparisons.

Parameters:

list - the list to be searched.

key - the key to be searched for.

c - the comparator by which the list is ordered.
         A <tt>null</tt> value indicates that the elements'
         natural ordering should be used.

Returns:

the index of the search key, if it is contained in the list;
         otherwise, <tt>(-(insertion point) - 1)</tt>.  The
         insertion point is defined as the point at which the
         key would be inserted into the list: the index of the first
         element greater than the key, or <tt>list.size()</tt> if all
         elements in the list are less than the specified key.  Note
         that this guarantees that the return value will be >= 0 if
         and only if the key is found.

Throws:

ClassCastException - if the list contains elements that are not
         mutually comparable using the specified comparator,
         or the search key is not mutually comparable with the
         elements of the list using this comparator.

reverse

public static void reverse(List<?> list)

Reverses the order of the elements in the specified list.

 This method runs in linear time.

Parameters:

list - the list whose elements are to be reversed.

Throws:

UnsupportedOperationException - if the specified list or
         its list-iterator does not support the <tt>set</tt> operation.

shuffle

public static void shuffle(List<?> list)

Randomly permutes the specified list using a default source of
 randomness.  All permutations occur with approximately equal
 likelihood.

 The hedge "approximately" is used in the foregoing description because
 default source of randomness is only approximately an unbiased source
 of independently chosen bits. If it were a perfect source of randomly
 chosen bits, then the algorithm would choose permutations with perfect
 uniformity.

 This implementation traverses the list backwards, from the last element
 up to the second, repeatedly swapping a randomly selected element into
 the "current position".  Elements are randomly selected from the
 portion of the list that runs from the first element to the current
 position, inclusive.

 This method runs in linear time.  If the specified list does not
 implement the RandomAccess interface and is large, this
 implementation dumps the specified list into an array before shuffling
 it, and dumps the shuffled array back into the list.  This avoids the
 quadratic behavior that would result from shuffling a "sequential
 access" list in place.

Parameters:

list - the list to be shuffled.

Throws:

UnsupportedOperationException - if the specified list or
         its list-iterator does not support the <tt>set</tt> operation.

shuffle

public static void shuffle(List<?> list,
           Random rnd)

Randomly permute the specified list using the specified source of
 randomness.  All permutations occur with equal likelihood
 assuming that the source of randomness is fair.

 This implementation traverses the list backwards, from the last element
 up to the second, repeatedly swapping a randomly selected element into
 the "current position".  Elements are randomly selected from the
 portion of the list that runs from the first element to the current
 position, inclusive.

 This method runs in linear time.  If the specified list does not
 implement the RandomAccess interface and is large, this
 implementation dumps the specified list into an array before shuffling
 it, and dumps the shuffled array back into the list.  This avoids the
 quadratic behavior that would result from shuffling a "sequential
 access" list in place.

Parameters:

list - the list to be shuffled.

rnd - the source of randomness to use to shuffle the list.

Throws:

UnsupportedOperationException - if the specified list or its
         list-iterator does not support the <tt>set</tt> operation.

swap

public static void swap(List<?> list,
        int i,
        int j)

Swaps the elements at the specified positions in the specified list.
 (If the specified positions are equal, invoking this method leaves
 the list unchanged.)

Parameters:

list - The list in which to swap elements.

i - the index of one element to be swapped.

j - the index of the other element to be swapped.

Throws:

IndexOutOfBoundsException - if either <tt>i</tt> or <tt>j</tt>
         is out of range (i < 0 || i >= list.size()
         || j < 0 || j >= list.size()).

Since:

1.4

fill

public static <T> void fill(List<? super T> list,
            T obj)

Replaces all of the elements of the specified list with the specified
 element.

 This method runs in linear time.

Parameters:

list - the list to be filled with the specified element.

obj - The element with which to fill the specified list.

Throws:

UnsupportedOperationException - if the specified list or its
         list-iterator does not support the <tt>set</tt> operation.

copy

public static <T> void copy(List<? super T> dest,
            List<? extends T> src)

Copies all of the elements from one list into another.  After the
 operation, the index of each copied element in the destination list
 will be identical to its index in the source list.  The destination
 list must be at least as long as the source list.  If it is longer, the
 remaining elements in the destination list are unaffected.

 This method runs in linear time.

Parameters:

dest - The destination list.

src - The source list.

Throws:

IndexOutOfBoundsException - if the destination list is too small
         to contain the entire source List.

UnsupportedOperationException - if the destination list's
         list-iterator does not support the <tt>set</tt> operation.

min

public static <T extends Object & Comparable<? super T>> T min(Collection<? extends T> coll)

Returns the minimum element of the given collection, according to the
 natural ordering of its elements.  All elements in the
 collection must implement the <tt>Comparable</tt> interface.
 Furthermore, all elements in the collection must be mutually
 comparable (that is, <tt>e1.compareTo(e2)</tt> must not throw a
 <tt>ClassCastException</tt> for any elements <tt>e1</tt> and
 <tt>e2</tt> in the collection).

 This method iterates over the entire collection, hence it requires
 time proportional to the size of the collection.

Parameters:

coll - the collection whose minimum element is to be determined.

Returns:

the minimum element of the given collection, according
         to the natural ordering of its elements.

Throws:

ClassCastException - if the collection contains elements that are
         not mutually comparable (for example, strings and
         integers).

NoSuchElementException - if the collection is empty.

See Also:

Comparable

min

public static <T> T min(Collection<? extends T> coll,
        Comparator<? super T> comp)

Returns the minimum element of the given collection, according to the
 order induced by the specified comparator.  All elements in the
 collection must be mutually comparable by the specified
 comparator (that is, <tt>comp.compare(e1, e2)</tt> must not throw a
 <tt>ClassCastException</tt> for any elements <tt>e1</tt> and
 <tt>e2</tt> in the collection).

 This method iterates over the entire collection, hence it requires
 time proportional to the size of the collection.

Parameters:

coll - the collection whose minimum element is to be determined.

comp - the comparator with which to determine the minimum element.
         A <tt>null</tt> value indicates that the elements' natural
         ordering should be used.

Returns:

the minimum element of the given collection, according
         to the specified comparator.

Throws:

ClassCastException - if the collection contains elements that are
         not mutually comparable using the specified comparator.

NoSuchElementException - if the collection is empty.

See Also:

Comparable

max

public static <T extends Object & Comparable<? super T>> T max(Collection<? extends T> coll)

Returns the maximum element of the given collection, according to the
 natural ordering of its elements.  All elements in the
 collection must implement the <tt>Comparable</tt> interface.
 Furthermore, all elements in the collection must be mutually
 comparable (that is, <tt>e1.compareTo(e2)</tt> must not throw a
 <tt>ClassCastException</tt> for any elements <tt>e1</tt> and
 <tt>e2</tt> in the collection).

 This method iterates over the entire collection, hence it requires
 time proportional to the size of the collection.

Parameters:

coll - the collection whose maximum element is to be determined.

Returns:

the maximum element of the given collection, according
         to the natural ordering of its elements.

Throws:

ClassCastException - if the collection contains elements that are
         not mutually comparable (for example, strings and
         integers).

NoSuchElementException - if the collection is empty.

See Also:

Comparable

max

public static <T> T max(Collection<? extends T> coll,
        Comparator<? super T> comp)

Returns the maximum element of the given collection, according to the
 order induced by the specified comparator.  All elements in the
 collection must be mutually comparable by the specified
 comparator (that is, <tt>comp.compare(e1, e2)</tt> must not throw a
 <tt>ClassCastException</tt> for any elements <tt>e1</tt> and
 <tt>e2</tt> in the collection).

 This method iterates over the entire collection, hence it requires
 time proportional to the size of the collection.

Parameters:

coll - the collection whose maximum element is to be determined.

comp - the comparator with which to determine the maximum element.
         A <tt>null</tt> value indicates that the elements' natural
        ordering should be used.

Returns:

the maximum element of the given collection, according
         to the specified comparator.

Throws:

ClassCastException - if the collection contains elements that are
         not mutually comparable using the specified comparator.

NoSuchElementException - if the collection is empty.

See Also:

Comparable

rotate

public static void rotate(List<?> list,
          int distance)

Rotates the elements in the specified list by the specified distance.
 After calling this method, the element at index <tt>i</tt> will be
 the element previously at index <tt>(i - distance)</tt> mod
 <tt>list.size()</tt>, for all values of <tt>i</tt> between <tt>0</tt>
 and <tt>list.size()-1</tt>, inclusive.  (This method has no effect on
 the size of the list.)

For example, suppose <tt>list</tt> comprises<tt> [t, a, n, k, s]</tt>.
 After invoking <tt>Collections.rotate(list, 1)</tt> (or
 <tt>Collections.rotate(list, -4)</tt>), <tt>list</tt> will comprise
 <tt>[s, t, a, n, k]</tt>.

Note that this method can usefully be applied to sublists to
 move one or more elements within a list while preserving the
 order of the remaining elements.  For example, the following idiom
 moves the element at index <tt>j</tt> forward to position
 <tt>k</tt> (which must be greater than or equal to <tt>j</tt>):

     Collections.rotate(list.subList(j, k+1), -1);

 To make this concrete, suppose <tt>list</tt> comprises
 <tt>[a, b, c, d, e]</tt>.  To move the element at index <tt>1</tt>
 (<tt>b</tt>) forward two positions, perform the following invocation:

     Collections.rotate(l.subList(1, 4), -1);

 The resulting list is <tt>[a, c, d, b, e]</tt>.

To move more than one element forward, increase the absolute value
 of the rotation distance.  To move elements backward, use a positive
 shift distance.

If the specified list is small or implements the RandomAccess interface, this implementation exchanges the first
 element into the location it should go, and then repeatedly exchanges
 the displaced element into the location it should go until a displaced
 element is swapped into the first element.  If necessary, the process
 is repeated on the second and successive elements, until the rotation
 is complete.  If the specified list is large and doesn't implement the
 <tt>RandomAccess</tt> interface, this implementation breaks the
 list into two sublist views around index <tt>-distance mod size</tt>.
 Then the reverse(List) method is invoked on each sublist view,
 and finally it is invoked on the entire list.  For a more complete
 description of both algorithms, see Section 2.3 of Jon Bentley's
 Programming Pearls (Addison-Wesley, 1986).

Parameters:

list - the list to be rotated.

distance - the distance to rotate the list.  There are no
        constraints on this value; it may be zero, negative, or
        greater than <tt>list.size()</tt>.

Throws:

UnsupportedOperationException - if the specified list or
         its list-iterator does not support the <tt>set</tt> operation.

Since:

1.4

replaceAll

public static <T> boolean replaceAll(List<T> list,
                     T oldVal,
                     T newVal)

Replaces all occurrences of one specified value in a list with another.
 More formally, replaces with <tt>newVal</tt> each element <tt>e</tt>
 in <tt>list</tt> such that
 <tt>(oldVal==null ? e==null : oldVal.equals(e))</tt>.
 (This method has no effect on the size of the list.)

Parameters:

list - the list in which replacement is to occur.

oldVal - the old value to be replaced.

newVal - the new value with which <tt>oldVal</tt> is to be
        replaced.

Returns:

<tt>true</tt> if <tt>list</tt> contained one or more elements
         <tt>e</tt> such that
         <tt>(oldVal==null ?  e==null : oldVal.equals(e))</tt>.

Throws:

UnsupportedOperationException - if the specified list or
         its list-iterator does not support the <tt>set</tt> operation.

Since:

1.4

indexOfSubList

public static int indexOfSubList(List<?> source,
                 List<?> target)

Returns the starting position of the first occurrence of the specified
 target list within the specified source list, or -1 if there is no
 such occurrence.  More formally, returns the lowest index <tt>i</tt>
 such that <tt>source.subList(i, i+target.size()).equals(target)</tt>,
 or -1 if there is no such index.  (Returns -1 if
 <tt>target.size() > source.size()</tt>.)

This implementation uses the "brute force" technique of scanning
 over the source list, looking for a match with the target at each
 location in turn.

Parameters:

source - the list in which to search for the first occurrence
        of <tt>target</tt>.

target - the list to search for as a subList of <tt>source</tt>.

Returns:

the starting position of the first occurrence of the specified
         target list within the specified source list, or -1 if there
         is no such occurrence.

Since:

1.4

lastIndexOfSubList

public static int lastIndexOfSubList(List<?> source,
                     List<?> target)

Returns the starting position of the last occurrence of the specified
 target list within the specified source list, or -1 if there is no such
 occurrence.  More formally, returns the highest index <tt>i</tt>
 such that <tt>source.subList(i, i+target.size()).equals(target)</tt>,
 or -1 if there is no such index.  (Returns -1 if
 <tt>target.size() > source.size()</tt>.)

This implementation uses the "brute force" technique of iterating
 over the source list, looking for a match with the target at each
 location in turn.

Parameters:

source - the list in which to search for the last occurrence
        of <tt>target</tt>.

target - the list to search for as a subList of <tt>source</tt>.

Returns:

the starting position of the last occurrence of the specified
         target list within the specified source list, or -1 if there
         is no such occurrence.

Since:

1.4

unmodifiableCollection

public static <T> Collection<T> unmodifiableCollection(Collection<? extends T> c)

Returns an unmodifiable view of the specified collection.  This method
 allows modules to provide users with "read-only" access to internal
 collections.  Query operations on the returned collection "read through"
 to the specified collection, and attempts to modify the returned
 collection, whether direct or via its iterator, result in an
 <tt>UnsupportedOperationException</tt>.

 The returned collection does not pass the hashCode and equals
 operations through to the backing collection, but relies on
 <tt>Object</tt>'s <tt>equals</tt> and <tt>hashCode</tt> methods.  This
 is necessary to preserve the contracts of these operations in the case
 that the backing collection is a set or a list.

 The returned collection will be serializable if the specified collection
 is serializable.

Parameters:

c - the collection for which an unmodifiable view is to be
         returned.

Returns:

an unmodifiable view of the specified collection.

unmodifiableSet

public static <T> Set<T> unmodifiableSet(Set<? extends T> s)

Returns an unmodifiable view of the specified set.  This method allows
 modules to provide users with "read-only" access to internal sets.
 Query operations on the returned set "read through" to the specified
 set, and attempts to modify the returned set, whether direct or via its
 iterator, result in an <tt>UnsupportedOperationException</tt>.

 The returned set will be serializable if the specified set
 is serializable.

Parameters:

s - the set for which an unmodifiable view is to be returned.

Returns:

an unmodifiable view of the specified set.

unmodifiableSortedSet

public static <T> SortedSet<T> unmodifiableSortedSet(SortedSet<T> s)

Returns an unmodifiable view of the specified sorted set.  This method
 allows modules to provide users with "read-only" access to internal
 sorted sets.  Query operations on the returned sorted set "read
 through" to the specified sorted set.  Attempts to modify the returned
 sorted set, whether direct, via its iterator, or via its
 <tt>subSet</tt>, <tt>headSet</tt>, or <tt>tailSet</tt> views, result in
 an <tt>UnsupportedOperationException</tt>.

 The returned sorted set will be serializable if the specified sorted set
 is serializable.

Parameters:

s - the sorted set for which an unmodifiable view is to be
        returned.

Returns:

an unmodifiable view of the specified sorted set.

unmodifiableList

public static <T> List<T> unmodifiableList(List<? extends T> list)

Returns an unmodifiable view of the specified list.  This method allows
 modules to provide users with "read-only" access to internal
 lists.  Query operations on the returned list "read through" to the
 specified list, and attempts to modify the returned list, whether
 direct or via its iterator, result in an
 <tt>UnsupportedOperationException</tt>.

 The returned list will be serializable if the specified list
 is serializable. Similarly, the returned list will implement
 RandomAccess if the specified list does.

Parameters:

list - the list for which an unmodifiable view is to be returned.

Returns:

an unmodifiable view of the specified list.

unmodifiableMap

public static <K,V> Map<K,V> unmodifiableMap(Map<? extends K,? extends V> m)

Returns an unmodifiable view of the specified map.  This method
 allows modules to provide users with "read-only" access to internal
 maps.  Query operations on the returned map "read through"
 to the specified map, and attempts to modify the returned
 map, whether direct or via its collection views, result in an
 <tt>UnsupportedOperationException</tt>.

 The returned map will be serializable if the specified map
 is serializable.

Parameters:

m - the map for which an unmodifiable view is to be returned.

Returns:

an unmodifiable view of the specified map.

unmodifiableSortedMap

public static <K,V> SortedMap<K,V> unmodifiableSortedMap(SortedMap<K,? extends V> m)

Returns an unmodifiable view of the specified sorted map.  This method
 allows modules to provide users with "read-only" access to internal
 sorted maps.  Query operations on the returned sorted map "read through"
 to the specified sorted map.  Attempts to modify the returned
 sorted map, whether direct, via its collection views, or via its
 <tt>subMap</tt>, <tt>headMap</tt>, or <tt>tailMap</tt> views, result in
 an <tt>UnsupportedOperationException</tt>.

 The returned sorted map will be serializable if the specified sorted map
 is serializable.

Parameters:

m - the sorted map for which an unmodifiable view is to be
        returned.

Returns:

an unmodifiable view of the specified sorted map.

synchronizedCollection

public static <T> Collection<T> synchronizedCollection(Collection<T> c)

Returns a synchronized (thread-safe) collection backed by the specified
 collection.  In order to guarantee serial access, it is critical that
 all access to the backing collection is accomplished
 through the returned collection.

 It is imperative that the user manually synchronize on the returned
 collection when iterating over it:

  Collection c = Collections.synchronizedCollection(myCollection);
     ...
  synchronized (c) {
      Iterator i = c.iterator(); // Must be in the synchronized block
      while (i.hasNext())
         foo(i.next());
  }

 Failure to follow this advice may result in non-deterministic behavior.

The returned collection does not pass the <tt>hashCode</tt>
 and <tt>equals</tt> operations through to the backing collection, but
 relies on <tt>Object</tt>'s equals and hashCode methods.  This is
 necessary to preserve the contracts of these operations in the case
 that the backing collection is a set or a list.

 The returned collection will be serializable if the specified collection
 is serializable.

Parameters:

c - the collection to be "wrapped" in a synchronized collection.

Returns:

a synchronized view of the specified collection.

synchronizedSet

public static <T> Set<T> synchronizedSet(Set<T> s)

Returns a synchronized (thread-safe) set backed by the specified
 set.  In order to guarantee serial access, it is critical that
 all access to the backing set is accomplished
 through the returned set.

 It is imperative that the user manually synchronize on the returned
 set when iterating over it:

  Set s = Collections.synchronizedSet(new HashSet());
      ...
  synchronized (s) {
      Iterator i = s.iterator(); // Must be in the synchronized block
      while (i.hasNext())
          foo(i.next());
  }

 Failure to follow this advice may result in non-deterministic behavior.

The returned set will be serializable if the specified set is
 serializable.

Parameters:

s - the set to be "wrapped" in a synchronized set.

Returns:

a synchronized view of the specified set.

synchronizedSortedSet

public static <T> SortedSet<T> synchronizedSortedSet(SortedSet<T> s)

Returns a synchronized (thread-safe) sorted set backed by the specified
 sorted set.  In order to guarantee serial access, it is critical that
 all access to the backing sorted set is accomplished
 through the returned sorted set (or its views).

 It is imperative that the user manually synchronize on the returned
 sorted set when iterating over it or any of its <tt>subSet</tt>,
 <tt>headSet</tt>, or <tt>tailSet</tt> views.

  SortedSet s = Collections.synchronizedSortedSet(new TreeSet());
      ...
  synchronized (s) {
      Iterator i = s.iterator(); // Must be in the synchronized block
      while (i.hasNext())
          foo(i.next());
  }

 or:

  SortedSet s = Collections.synchronizedSortedSet(new TreeSet());
  SortedSet s2 = s.headSet(foo);
      ...
  synchronized (s) {  // Note: s, not s2!!!
      Iterator i = s2.iterator(); // Must be in the synchronized block
      while (i.hasNext())
          foo(i.next());
  }

 Failure to follow this advice may result in non-deterministic behavior.

The returned sorted set will be serializable if the specified
 sorted set is serializable.

Parameters:

s - the sorted set to be "wrapped" in a synchronized sorted set.

Returns:

a synchronized view of the specified sorted set.

synchronizedList

public static <T> List<T> synchronizedList(List<T> list)

Returns a synchronized (thread-safe) list backed by the specified
 list.  In order to guarantee serial access, it is critical that
 all access to the backing list is accomplished
 through the returned list.

 It is imperative that the user manually synchronize on the returned
 list when iterating over it:

  List list = Collections.synchronizedList(new ArrayList());
      ...
  synchronized (list) {
      Iterator i = list.iterator(); // Must be in synchronized block
      while (i.hasNext())
          foo(i.next());
  }

 Failure to follow this advice may result in non-deterministic behavior.

The returned list will be serializable if the specified list is
 serializable.

Parameters:

list - the list to be "wrapped" in a synchronized list.

Returns:

a synchronized view of the specified list.

synchronizedMap

public static <K,V> Map<K,V> synchronizedMap(Map<K,V> m)

Returns a synchronized (thread-safe) map backed by the specified
 map.  In order to guarantee serial access, it is critical that
 all access to the backing map is accomplished
 through the returned map.

 It is imperative that the user manually synchronize on the returned
 map when iterating over any of its collection views:

  Map m = Collections.synchronizedMap(new HashMap());
      ...
  Set s = m.keySet();  // Needn't be in synchronized block
      ...
  synchronized (m) {  // Synchronizing on m, not s!
      Iterator i = s.iterator(); // Must be in synchronized block
      while (i.hasNext())
          foo(i.next());
  }

 Failure to follow this advice may result in non-deterministic behavior.

The returned map will be serializable if the specified map is
 serializable.

Parameters:

m - the map to be "wrapped" in a synchronized map.

Returns:

a synchronized view of the specified map.

synchronizedSortedMap

public static <K,V> SortedMap<K,V> synchronizedSortedMap(SortedMap<K,V> m)

Returns a synchronized (thread-safe) sorted map backed by the specified
 sorted map.  In order to guarantee serial access, it is critical that
 all access to the backing sorted map is accomplished
 through the returned sorted map (or its views).

 It is imperative that the user manually synchronize on the returned
 sorted map when iterating over any of its collection views, or the
 collections views of any of its <tt>subMap</tt>, <tt>headMap</tt> or
 <tt>tailMap</tt> views.

  SortedMap m = Collections.synchronizedSortedMap(new TreeMap());
      ...
  Set s = m.keySet();  // Needn't be in synchronized block
      ...
  synchronized (m) {  // Synchronizing on m, not s!
      Iterator i = s.iterator(); // Must be in synchronized block
      while (i.hasNext())
          foo(i.next());
  }

 or:

  SortedMap m = Collections.synchronizedSortedMap(new TreeMap());
  SortedMap m2 = m.subMap(foo, bar);
      ...
  Set s2 = m2.keySet();  // Needn't be in synchronized block
      ...
  synchronized (m) {  // Synchronizing on m, not m2 or s2!
      Iterator i = s.iterator(); // Must be in synchronized block
      while (i.hasNext())
          foo(i.next());
  }

 Failure to follow this advice may result in non-deterministic behavior.

The returned sorted map will be serializable if the specified
 sorted map is serializable.

Parameters:

m - the sorted map to be "wrapped" in a synchronized sorted map.

Returns:

a synchronized view of the specified sorted map.

checkedCollection

public static <E> Collection<E> checkedCollection(Collection<E> c,
                                  Class<E> type)

Returns a dynamically typesafe view of the specified collection.
 Any attempt to insert an element of the wrong type will result in an
 immediate ClassCastException.  Assuming a collection
 contains no incorrectly typed elements prior to the time a
 dynamically typesafe view is generated, and that all subsequent
 access to the collection takes place through the view, it is
 guaranteed that the collection cannot contain an incorrectly
 typed element.

The generics mechanism in the language provides compile-time
 (static) type checking, but it is possible to defeat this mechanism
 with unchecked casts.  Usually this is not a problem, as the compiler
 issues warnings on all such unchecked operations.  There are, however,
 times when static type checking alone is not sufficient.  For example,
 suppose a collection is passed to a third-party library and it is
 imperative that the library code not corrupt the collection by
 inserting an element of the wrong type.

Another use of dynamically typesafe views is debugging.  Suppose a
 program fails with a ClassCastException, indicating that an
 incorrectly typed element was put into a parameterized collection.
 Unfortunately, the exception can occur at any time after the erroneous
 element is inserted, so it typically provides little or no information
 as to the real source of the problem.  If the problem is reproducible,
 one can quickly determine its source by temporarily modifying the
 program to wrap the collection with a dynamically typesafe view.
 For example, this declaration:

 Collection<String> c = new HashSet<String>();

 may be replaced temporarily by this one:

 Collection<String> c = Collections.checkedCollection(
         new HashSet<String>(), String.class);

 Running the program again will cause it to fail at the point where
 an incorrectly typed element is inserted into the collection, clearly
 identifying the source of the problem.  Once the problem is fixed, the
 modified declaration may be reverted back to the original.

The returned collection does not pass the hashCode and equals
 operations through to the backing collection, but relies on
 Object's equals and hashCode methods.  This
 is necessary to preserve the contracts of these operations in the case
 that the backing collection is a set or a list.

The returned collection will be serializable if the specified
 collection is serializable.

Since null is considered to be a value of any reference
 type, the returned collection permits insertion of null elements
 whenever the backing collection does.

Parameters:

c - the collection for which a dynamically typesafe view is to be
          returned

type - the type of element that c is permitted to hold

Returns:

a dynamically typesafe view of the specified collection

Since:

1.5

checkedSet

public static <E> Set<E> checkedSet(Set<E> s,
                    Class<E> type)

Returns a dynamically typesafe view of the specified set.
 Any attempt to insert an element of the wrong type will result in
 an immediate ClassCastException.  Assuming a set contains
 no incorrectly typed elements prior to the time a dynamically typesafe
 view is generated, and that all subsequent access to the set
 takes place through the view, it is guaranteed that the
 set cannot contain an incorrectly typed element.

A discussion of the use of dynamically typesafe views may be
 found in the documentation for the checkedCollection method.

The returned set will be serializable if the specified set is
 serializable.

Since null is considered to be a value of any reference
 type, the returned set permits insertion of null elements whenever
 the backing set does.

Parameters:

s - the set for which a dynamically typesafe view is to be
          returned

type - the type of element that s is permitted to hold

Returns:

a dynamically typesafe view of the specified set

Since:

1.5

checkedSortedSet

public static <E> SortedSet<E> checkedSortedSet(SortedSet<E> s,
                                Class<E> type)

Returns a dynamically typesafe view of the specified sorted set.
 Any attempt to insert an element of the wrong type will result in an
 immediate ClassCastException.  Assuming a sorted set
 contains no incorrectly typed elements prior to the time a
 dynamically typesafe view is generated, and that all subsequent
 access to the sorted set takes place through the view, it is
 guaranteed that the sorted set cannot contain an incorrectly
 typed element.

A discussion of the use of dynamically typesafe views may be
 found in the documentation for the checkedCollection method.

The returned sorted set will be serializable if the specified sorted
 set is serializable.

Since null is considered to be a value of any reference
 type, the returned sorted set permits insertion of null elements
 whenever the backing sorted set does.

Parameters:

s - the sorted set for which a dynamically typesafe view is to be
          returned

type - the type of element that s is permitted to hold

Returns:

a dynamically typesafe view of the specified sorted set

Since:

1.5

checkedList

public static <E> List<E> checkedList(List<E> list,
                      Class<E> type)

Returns a dynamically typesafe view of the specified list.
 Any attempt to insert an element of the wrong type will result in
 an immediate ClassCastException.  Assuming a list contains
 no incorrectly typed elements prior to the time a dynamically typesafe
 view is generated, and that all subsequent access to the list
 takes place through the view, it is guaranteed that the
 list cannot contain an incorrectly typed element.

A discussion of the use of dynamically typesafe views may be
 found in the documentation for the checkedCollection method.

The returned list will be serializable if the specified list
 is serializable.

Since null is considered to be a value of any reference
 type, the returned list permits insertion of null elements whenever
 the backing list does.

Parameters:

list - the list for which a dynamically typesafe view is to be
             returned

type - the type of element that list is permitted to hold

Returns:

a dynamically typesafe view of the specified list

Since:

1.5

checkedMap

public static <K,V> Map<K,V> checkedMap(Map<K,V> m,
                        Class<K> keyType,
                        Class<V> valueType)

Returns a dynamically typesafe view of the specified map.
 Any attempt to insert a mapping whose key or value have the wrong
 type will result in an immediate ClassCastException.
 Similarly, any attempt to modify the value currently associated with
 a key will result in an immediate ClassCastException,
 whether the modification is attempted directly through the map
 itself, or through a Map.Entry instance obtained from the
 map's entry set view.

Assuming a map contains no incorrectly typed keys or values
 prior to the time a dynamically typesafe view is generated, and
 that all subsequent access to the map takes place through the view
 (or one of its collection views), it is guaranteed that the
 map cannot contain an incorrectly typed key or value.

A discussion of the use of dynamically typesafe views may be
 found in the documentation for the checkedCollection method.

The returned map will be serializable if the specified map is
 serializable.

Since null is considered to be a value of any reference
 type, the returned map permits insertion of null keys or values
 whenever the backing map does.

Parameters:

m - the map for which a dynamically typesafe view is to be
          returned

keyType - the type of key that m is permitted to hold

valueType - the type of value that m is permitted to hold

Returns:

a dynamically typesafe view of the specified map

Since:

1.5

checkedSortedMap

public static <K,V> SortedMap<K,V> checkedSortedMap(SortedMap<K,V> m,
                                    Class<K> keyType,
                                    Class<V> valueType)

Returns a dynamically typesafe view of the specified sorted map.
 Any attempt to insert a mapping whose key or value have the wrong
 type will result in an immediate ClassCastException.
 Similarly, any attempt to modify the value currently associated with
 a key will result in an immediate ClassCastException,
 whether the modification is attempted directly through the map
 itself, or through a Map.Entry instance obtained from the
 map's entry set view.

Assuming a map contains no incorrectly typed keys or values
 prior to the time a dynamically typesafe view is generated, and
 that all subsequent access to the map takes place through the view
 (or one of its collection views), it is guaranteed that the
 map cannot contain an incorrectly typed key or value.

A discussion of the use of dynamically typesafe views may be
 found in the documentation for the checkedCollection method.

The returned map will be serializable if the specified map is
 serializable.

Since null is considered to be a value of any reference
 type, the returned map permits insertion of null keys or values
 whenever the backing map does.

Parameters:

m - the map for which a dynamically typesafe view is to be
          returned

keyType - the type of key that m is permitted to hold

valueType - the type of value that m is permitted to hold

Returns:

a dynamically typesafe view of the specified map

Since:

1.5

emptyIterator

public static <T> Iterator<T> emptyIterator()

Returns an iterator that has no elements.  More precisely,

hasNext always returns false.

next always throws NoSuchElementException.

remove always throws IllegalStateException.

Implementations of this method are permitted, but not
 required, to return the same object from multiple invocations.

Returns:

an empty iterator

Since:

1.7

emptyListIterator

public static <T> ListIterator<T> emptyListIterator()

Returns a list iterator that has no elements.  More precisely,

hasNext and hasPrevious always return false.

next and previous always throw NoSuchElementException.

remove and set always throw IllegalStateException.

add always throws UnsupportedOperationException.

nextIndex always returns
 0 .

previousIndex always
 returns -1.

Implementations of this method are permitted, but not
 required, to return the same object from multiple invocations.

Returns:

an empty list iterator

Since:

1.7

emptyEnumeration

public static <T> Enumeration<T> emptyEnumeration()

Returns an enumeration that has no elements.  More precisely,

hasMoreElements always
 returns false.

 nextElement always throws
 NoSuchElementException.

Implementations of this method are permitted, but not
 required, to return the same object from multiple invocations.

Returns:

an empty enumeration

Since:

1.7

emptySet

public static final <T> Set<T> emptySet()

Returns the empty set (immutable).  This set is serializable.
 Unlike the like-named field, this method is parameterized.

This example illustrates the type-safe way to obtain an empty set:

     Set<String> s = Collections.emptySet();

 Implementation note:  Implementations of this method need not
 create a separate <tt>Set</tt> object for each call.   Using this
 method is likely to have comparable cost to using the like-named
 field.  (Unlike this method, the field does not provide type safety.)

Since:

1.5

See Also:

EMPTY_SET

emptyList

public static final <T> List<T> emptyList()

Returns the empty list (immutable).  This list is serializable.

This example illustrates the type-safe way to obtain an empty list:

     List<String> s = Collections.emptyList();

 Implementation note:  Implementations of this method need not
 create a separate <tt>List</tt> object for each call.   Using this
 method is likely to have comparable cost to using the like-named
 field.  (Unlike this method, the field does not provide type safety.)

Since:

1.5

See Also:

EMPTY_LIST

emptyMap

public static final <K,V> Map<K,V> emptyMap()

Returns the empty map (immutable).  This map is serializable.

This example illustrates the type-safe way to obtain an empty set:

     Map<String, Date> s = Collections.emptyMap();

 Implementation note:  Implementations of this method need not
 create a separate <tt>Map</tt> object for each call.   Using this
 method is likely to have comparable cost to using the like-named
 field.  (Unlike this method, the field does not provide type safety.)

Since:

1.5

See Also:

EMPTY_MAP

singleton

public static <T> Set<T> singleton(T o)

Returns an immutable set containing only the specified object.
 The returned set is serializable.

Parameters:

o - the sole object to be stored in the returned set.

Returns:

an immutable set containing only the specified object.

singletonList

public static <T> List<T> singletonList(T o)

Returns an immutable list containing only the specified object.
 The returned list is serializable.

Parameters:

o - the sole object to be stored in the returned list.

Returns:

an immutable list containing only the specified object.

Since:

1.3

singletonMap

public static <K,V> Map<K,V> singletonMap(K key,
                          V value)

Returns an immutable map, mapping only the specified key to the
 specified value.  The returned map is serializable.

Parameters:

key - the sole key to be stored in the returned map.

value - the value to which the returned map maps <tt>key</tt>.

Returns:

an immutable map containing only the specified key-value
         mapping.

Since:

1.3

nCopies

public static <T> List<T> nCopies(int n,
                  T o)

Returns an immutable list consisting of <tt>n</tt> copies of the
 specified object.  The newly allocated data object is tiny (it contains
 a single reference to the data object).  This method is useful in
 combination with the <tt>List.addAll</tt> method to grow lists.
 The returned list is serializable.

Parameters:

n - the number of elements in the returned list.

o - the element to appear repeatedly in the returned list.

Returns:

an immutable list consisting of <tt>n</tt> copies of the
         specified object.

Throws:

IllegalArgumentException - if n < 0

See Also:

List.addAll(Collection),
List.addAll(int, Collection)

reverseOrder

public static <T> Comparator<T> reverseOrder()

Returns a comparator that imposes the reverse of the natural
 ordering on a collection of objects that implement the
 Comparable interface.  (The natural ordering is the ordering
 imposed by the objects' own compareTo method.)  This enables a
 simple idiom for sorting (or maintaining) collections (or arrays) of
 objects that implement the Comparable interface in
 reverse-natural-order.  For example, suppose a is an array of
 strings. Then:

          Arrays.sort(a, Collections.reverseOrder());

 sorts the array in reverse-lexicographic (alphabetical) order.

 The returned comparator is serializable.

Returns:

A comparator that imposes the reverse of the natural
         ordering on a collection of objects that implement
         the <tt>Comparable</tt> interface.

See Also:

Comparable

reverseOrder

public static <T> Comparator<T> reverseOrder(Comparator<T> cmp)

Returns a comparator that imposes the reverse ordering of the specified
 comparator.  If the specified comparator is null, this method is
 equivalent to reverseOrder() (in other words, it returns a
 comparator that imposes the reverse of the natural ordering on
 a collection of objects that implement the Comparable interface).

The returned comparator is serializable (assuming the specified
 comparator is also serializable or null).

Parameters:

cmp - a comparator who's ordering is to be reversed by the returned
 comparator or null

Returns:

A comparator that imposes the reverse ordering of the
         specified comparator.

Since:

1.5

enumeration

public static <T> Enumeration<T> enumeration(Collection<T> c)

Returns an enumeration over the specified collection.  This provides
 interoperability with legacy APIs that require an enumeration
 as input.

Parameters:

c - the collection for which an enumeration is to be returned.

Returns:

an enumeration over the specified collection.

See Also:

Enumeration

list

public static <T> ArrayList<T> list(Enumeration<T> e)

Returns an array list containing the elements returned by the
 specified enumeration in the order they are returned by the
 enumeration.  This method provides interoperability between
 legacy APIs that return enumerations and new APIs that require
 collections.

Parameters:

e - enumeration providing elements for the returned
          array list

Returns:

an array list containing the elements returned
         by the specified enumeration.

Since:

1.4

See Also:

Enumeration,
ArrayList

frequency

public static int frequency(Collection<?> c,
            Object o)

Returns the number of elements in the specified collection equal to the
 specified object.  More formally, returns the number of elements
 <tt>e</tt> in the collection such that
 <tt>(o == null ? e == null : o.equals(e))</tt>.

Parameters:

c - the collection in which to determine the frequency
     of <tt>o</tt>

o - the object whose frequency is to be determined

Throws:

NullPointerException - if <tt>c</tt> is null

Since:

1.5

disjoint

public static boolean disjoint(Collection<?> c1,
               Collection<?> c2)

Returns true if the two specified collections have no
 elements in common.

Care must be exercised if this method is used on collections that
 do not comply with the general contract for Collection.
 Implementations may elect to iterate over either collection and test
 for containment in the other collection (or to perform any equivalent
 computation).  If either collection uses a nonstandard equality test
 (as does a SortedSet whose ordering is not compatible with
 equals, or the key set of an IdentityHashMap), both
 collections must use the same nonstandard equality test, or the
 result of this method is undefined.

Care must also be exercised when using collections that have
 restrictions on the elements that they may contain. Collection
 implementations are allowed to throw exceptions for any operation
 involving elements they deem ineligible. For absolute safety the
 specified collections should contain only elements which are
 eligible elements for both collections.

Note that it is permissible to pass the same collection in both
 parameters, in which case the method will return true if and
 only if the collection is empty.

Parameters:

c1 - a collection

c2 - a collection

Returns:

true if the two specified collections have no
 elements in common.

Throws:

NullPointerException - if either collection is null.

NullPointerException - if one collection contains a null
 element and null is not an eligible element for the other collection.
 (optional)

ClassCastException - if one collection contains an element that is
 of a type which is ineligible for the other collection.
 (optional)

Since:

1.5

addAll

@SafeVarargs
public static <T> boolean addAll(Collection<? super T> c,
                             T... elements)

Adds all of the specified elements to the specified collection.
 Elements to be added may be specified individually or as an array.
 The behavior of this convenience method is identical to that of
 <tt>c.addAll(Arrays.asList(elements))</tt>, but this method is likely
 to run significantly faster under most implementations.

When elements are specified individually, this method provides a
 convenient way to add a few elements to an existing collection:

     Collections.addAll(flavors, "Peaches 'n Plutonium", "Rocky Racoon");

Parameters:

c - the collection into which <tt>elements</tt> are to be inserted

elements - the elements to insert into <tt>c</tt>

Returns:

<tt>true</tt> if the collection changed as a result of the call

Throws:

UnsupportedOperationException - if <tt>c</tt> does not support
         the <tt>add</tt> operation

NullPointerException - if <tt>elements</tt> contains one or more
         null values and <tt>c</tt> does not permit null elements, or
         if <tt>c</tt> or <tt>elements</tt> are <tt>null</tt>

IllegalArgumentException - if some property of a value in
         <tt>elements</tt> prevents it from being added to <tt>c</tt>

Since:

1.5

See Also:

Collection.addAll(Collection)

newSetFromMap

public static <E> Set<E> newSetFromMap(Map<E,Boolean> map)

Returns a set backed by the specified map.  The resulting set displays
 the same ordering, concurrency, and performance characteristics as the
 backing map.  In essence, this factory method provides a Set
 implementation corresponding to any Map implementation.  There
 is no need to use this method on a Map implementation that
 already has a corresponding Set implementation (such as HashMap or TreeMap).

Each method invocation on the set returned by this method results in
 exactly one method invocation on the backing map or its <tt>keySet</tt>
 view, with one exception.  The <tt>addAll</tt> method is implemented
 as a sequence of <tt>put</tt> invocations on the backing map.

The specified map must be empty at the time this method is invoked,
 and should not be accessed directly after this method returns.  These
 conditions are ensured if the map is created empty, passed directly
 to this method, and no reference to the map is retained, as illustrated
 in the following code fragment:

    Set<Object> weakHashSet = Collections.newSetFromMap(
        new WeakHashMap<Object, Boolean>());

Parameters:

map - the backing map

Returns:

the set backed by the map

Throws:

IllegalArgumentException - if <tt>map</tt> is not empty

Since:

1.6

asLifoQueue

public static <T> Queue<T> asLifoQueue(Deque<T> deque)

Returns a view of a Deque as a Last-in-first-out (Lifo)
 Queue. Method <tt>add</tt> is mapped to <tt>push</tt>,
 <tt>remove</tt> is mapped to <tt>pop</tt> and so on. This
 view can be useful when you would like to use a method
 requiring a <tt>Queue</tt> but you need Lifo ordering.

Each method invocation on the queue returned by this method
 results in exactly one method invocation on the backing deque, with
 one exception.  The addAll method is
 implemented as a sequence of addFirst
 invocations on the backing deque.

Parameters:

deque - the deque

Returns:

the queue

Since:

1.6

Overview

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For further API reference and developer documentation, see Java SE Documentation. That documentation contains more detailed, developer-targeted descriptions, with conceptual overviews, definitions of terms, workarounds, and working code examples.
 Copyright © 1993, 2015, Oracle and/or its affiliates.  All rights reserved.


text:
import sys
from twisted.internet import reactor
from twisted.names.srvconnect import SRVConnector
from twisted.words.xish import domish
from twisted.words.protocols.jabber import xmlstream, client, jid

class XMPPClientConnector(SRVConnector):
    def __init__(self, reactor, domain, factory):
        SRVConnector.__init__(self, reactor, 'xmpp-client', domain, factory)

    def pickServer(self):
        host, port = SRVConnector.pickServer(self)

        if not self.servers and not self.orderedServers:
            # no SRV record, fall back..
            port = 5222

        return host, port

class Client(object):
    def __init__(self, client_jid, secret):
        f = client.XMPPClientFactory(client_jid, secret)
        f.addBootstrap(xmlstream.STREAM_CONNECTED_EVENT, self.connected)
        f.addBootstrap(xmlstream.STREAM_END_EVENT, self.disconnected)
        f.addBootstrap(xmlstream.STREAM_AUTHD_EVENT, self.authenticated)
        f.addBootstrap(xmlstream.INIT_FAILED_EVENT, self.init_failed)
        connector = XMPPClientConnector(reactor, client_jid.host, f)
        connector.connect()

    def rawDataIn(self, buf):
        print "RECV: %s" % unicode(buf, 'utf-8').encode('ascii', 'replace')

    def rawDataOut(self, buf):
        print "SEND: %s" % unicode(buf, 'utf-8').encode('ascii', 'replace')

    def connected(self, xs):
        print 'Connected.'

        self.xmlstream = xs

        # Log all traffic
        xs.rawDataInFn = self.rawDataIn
        xs.rawDataOutFn = self.rawDataOut

    def disconnected(self, xs):
        print 'Disconnected.'

        reactor.stop()

    def authenticated(self, xs):
        print "Authenticated."

        presence = domish.Element((None, 'presence'))
        xs.send(presence)

        reactor.callLater(5, xs.sendFooter)

    def init_failed(self, failure):
        print "Initialization failed."
        print failure

        self.xmlstream.sendFooter()

client_jid = jid.JID(sys.argv[1])
secret = sys.argv[2]
c = Client(client_jid, secret)

reactor.run()

redpajama_set_name: RedPajamaGithub


text:
package com.datamart.wfpk;

/**
 * Created by r.stepanyak on 9/7/15.
 */
public interface VolumeChangeCallback {
    void volumeChanged(float newVolume);
}


text:
package com.navercorp.pinpoint.collector.mapper.flink;

import com.navercorp.pinpoint.common.server.bo.stat.AgentStatBo;
import com.navercorp.pinpoint.common.server.bo.stat.DataSourceBo;
import com.navercorp.pinpoint.common.server.bo.stat.DataSourceListBo;
import com.navercorp.pinpoint.thrift.dto.flink.TFAgentStat;
import com.navercorp.pinpoint.thrift.dto.flink.TFDataSource;
import com.navercorp.pinpoint.thrift.dto.flink.TFDataSourceList;
import org.springframework.stereotype.Component;

import java.util.ArrayList;
import java.util.List;

/**
 * @author minwoo.jung
 */
@Component
public class TFDataSourceListBoMapper implements FlinkStatMapper<DataSourceListBo, TFAgentStat> {

    private static final TFDataSourceBoMapper tFDataSourceBoMapper = new TFDataSourceBoMapper();

    public TFDataSourceList map(DataSourceListBo dataSourceListBo) {
        List<DataSourceBo> dataSourceBoList = dataSourceListBo.getList();
        List<TFDataSource> dataSourceList = new ArrayList<>(dataSourceBoList.size());

        for (DataSourceBo dataSourceBo : dataSourceBoList) {
            dataSourceList.add(tFDataSourceBoMapper.map(dataSourceBo));
        }

        TFDataSourceList tFDataSourceList = new TFDataSourceList();
        tFDataSourceList.setDataSourceList(dataSourceList);

        return tFDataSourceList;
    }

    @Override
    public void map(DataSourceListBo dataSourceListBo, TFAgentStat tfAgentStat) {
        tfAgentStat.setDataSourceList(map(dataSourceListBo));
    }

    @Override
    public void build(TFAgentStatMapper.TFAgentStatBuilder builder) {
        AgentStatBo agentStat = builder.getAgentStat();
        List<DataSourceListBo> dataSourceList = agentStat.getDataSourceListBos();
        builder.build(dataSourceList, this);
    }
}


text:
#pragma once

#include "esp_err.h"
#include "esp_intr_alloc.h"
#include "hal/touch_sensor_types.h"

#ifdef __cplusplus
extern "C" {
#endif

/**
 * @brief Initialize touch module.
 * @note  If default parameter don't match the usage scenario, it can be changed after this function.
 * @return
 *     - ESP_OK Success
 *     - ESP_ERR_NO_MEM Touch pad init error
 *     - ESP_ERR_NOT_SUPPORTED Touch pad is providing current to external XTAL
 */
esp_err_t touch_pad_init(void);

/**
 * @brief Un-install touch pad driver.
 * @note  After this function is called, other touch functions are prohibited from being called.
 * @return
 *     - ESP_OK   Success
 *     - ESP_FAIL Touch pad driver not initialized
 */
esp_err_t touch_pad_deinit(void);

/**
 * @brief Initialize touch pad GPIO
 * @param touch_num touch pad index
 * @return
 *      - ESP_OK on success
 *      - ESP_ERR_INVALID_ARG if argument is wrong
 */
esp_err_t touch_pad_io_init(touch_pad_t touch_num);

/**
 * @brief Set touch sensor high voltage threshold of chanrge.
 *        The touch sensor measures the channel capacitance value by charging and discharging the channel.
 *        So the high threshold should be less than the supply voltage.
 * @param refh the value of DREFH
 * @param refl the value of DREFL
 * @param atten the attenuation on DREFH
 * @return
 *      - ESP_OK on success
 *      - ESP_ERR_INVALID_ARG if argument is wrong
 */
esp_err_t touch_pad_set_voltage(touch_high_volt_t refh, touch_low_volt_t refl, touch_volt_atten_t atten);

/**
 * @brief Get touch sensor reference voltage,
 * @param refh pointer to accept DREFH value
 * @param refl pointer to accept DREFL value
 * @param atten pointer to accept the attenuation on DREFH
 * @return
 *      - ESP_OK on success
 */
esp_err_t touch_pad_get_voltage(touch_high_volt_t *refh, touch_low_volt_t *refl, touch_volt_atten_t *atten);

/**
 * @brief Set touch sensor charge/discharge speed for each pad.
 *        If the slope is 0, the counter would always be zero.
 *        If the slope is 1, the charging and discharging would be slow, accordingly.
 *        If the slope is set 7, which is the maximum value, the charging and discharging would be fast.
 * @note The higher the charge and discharge current, the greater the immunity of the touch channel,
 *       but it will increase the system power consumption.
 * @param touch_num touch pad index
 * @param slope touch pad charge/discharge speed
 * @param opt the initial voltage
 * @return
 *      - ESP_OK on success
 *      - ESP_ERR_INVALID_ARG if argument is wrong
 */
esp_err_t touch_pad_set_cnt_mode(touch_pad_t touch_num, touch_cnt_slope_t slope, touch_tie_opt_t opt);

/**
 * @brief Get touch sensor charge/discharge speed for each pad
 * @param touch_num touch pad index
 * @param slope pointer to accept touch pad charge/discharge slope
 * @param opt pointer to accept the initial voltage
 * @return
 *      - ESP_OK on success
 *      - ESP_ERR_INVALID_ARG if argument is wrong
 */
esp_err_t touch_pad_get_cnt_mode(touch_pad_t touch_num, touch_cnt_slope_t *slope, touch_tie_opt_t *opt);

/**
 * @brief Deregister the handler previously registered using touch_pad_isr_handler_register
 * @param fn  handler function to call (as passed to touch_pad_isr_handler_register)
 * @param arg  argument of the handler (as passed to touch_pad_isr_handler_register)
 * @return
 *      - ESP_OK on success
 *      - ESP_ERR_INVALID_STATE if a handler matching both fn and
 *        arg isn't registered
 */
esp_err_t touch_pad_isr_deregister(void(*fn)(void *), void *arg);

/**
 * @brief Get the touch pad which caused wakeup from deep sleep.
 * @param pad_num pointer to touch pad which caused wakeup
 * @return
 *      - ESP_OK Success
 *      - ESP_ERR_INVALID_ARG parameter is NULL
 */
esp_err_t touch_pad_get_wakeup_status(touch_pad_t *pad_num);

/**
 * @brief Set touch sensor FSM mode, the test action can be triggered by the timer,
 *        as well as by the software.
 * @param mode FSM mode
 * @return
 *      - ESP_OK on success
 *      - ESP_ERR_INVALID_ARG if argument is wrong
 */
esp_err_t touch_pad_set_fsm_mode(touch_fsm_mode_t mode);

/**
 * @brief Get touch sensor FSM mode
 * @param mode pointer to accept FSM mode
 * @return
 *      - ESP_OK on success
 */
esp_err_t touch_pad_get_fsm_mode(touch_fsm_mode_t *mode);

/**
 * @brief To clear the touch sensor channel active status.
 *
 * @note The FSM automatically updates the touch sensor status. It is generally not necessary to call this API to clear the status.
 * @return
 *      - ESP_OK on success
 */
esp_err_t touch_pad_clear_status(void);

/**
 * @brief Get the touch sensor channel active status mask.
 *        The bit position represents the channel number. The 0/1 status of the bit represents the trigger status.
 *
 * @return
 *      - The touch sensor status. e.g. Touch1 trigger status is `status_mask & (BIT1)`.
 */
uint32_t touch_pad_get_status(void);

/**
 * @brief Check touch sensor measurement status.
 *
 * @return
 *      - True measurement is under way
 *      - False measurement done
 */
bool touch_pad_meas_is_done(void);

#ifdef __cplusplus
}
#endif


text:
// File System.Linq.Expressions.RuntimeVariablesExpression.cs
// Automatically generated contract file.
using System.Collections.Generic;
using System.IO;
using System.Text;
using System.Diagnostics.Contracts;
using System;

// Disable the "this variable is not used" warning as every field would imply it.
#pragma warning disable 0414
// Disable the "this variable is never assigned to".
#pragma warning disable 0067
// Disable the "this event is never assigned to".
#pragma warning disable 0649
// Disable the "this variable is never used".
#pragma warning disable 0169
// Disable the "new keyword not required" warning.
#pragma warning disable 0109
// Disable the "extern without DllImport" warning.
#pragma warning disable 0626
// Disable the "could hide other member" warning, can happen on certain properties.
#pragma warning disable 0108

namespace System.Linq.Expressions
{
  sealed public partial class RuntimeVariablesExpression : Expression
  {
    #region Methods and constructors
    protected internal override Expression Accept(ExpressionVisitor visitor)
    {
      return default(Expression);
    }

    internal RuntimeVariablesExpression()
    {
    }

    public RuntimeVariablesExpression Update(IEnumerable<ParameterExpression> variables)
    {
      Contract.Ensures(Contract.Result<System.Linq.Expressions.RuntimeVariablesExpression>() != null);

      return default(RuntimeVariablesExpression);
    }
    #endregion

    #region Properties and indexers
    public override ExpressionType NodeType
    {
      get
      {
        return default(ExpressionType);
      }
    }

    public override Type Type
    {
      get
      {
        return default(Type);
      }
    }

    public System.Collections.ObjectModel.ReadOnlyCollection<ParameterExpression> Variables
    {
      get
      {
        return default(System.Collections.ObjectModel.ReadOnlyCollection<ParameterExpression>);
      }
    }
    #endregion
  }
}


text:
package synapticloop.linode.api.response;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

import org.json.JSONArray;
import org.json.JSONObject;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import synapticloop.linode.api.response.bean.ApiError;

public abstract class BaseResponse extends BaseJsonReader {
	private static final Logger LOGGER = LoggerFactory.getLogger(BaseResponse.class);

	private static final String JSON_KEY_ACTION = "ACTION";
	protected static final String JSON_KEY_DATA = "DATA";
	protected static final String JSON_KEY_ERRORARRAY = "ERRORARRAY";
	protected static final String JSON_KEY_VERSION = "VERSION";
	protected static final String JSON_KEY_METHODS = "METHODS";
	protected static final String JSON_KEY_INVOICE_TO = "INVOICE_TO";
	protected static final String JSON_KEY_AMOUNT = "AMOUNT";
	protected static final String JSON_KEY_BALANCE = "BALANCE";
	protected static final String JSON_KEY_BILLING_METHOD = "BILLING_METHOD";
	protected static final String JSON_KEY_MANAGED = "MANAGED";
	protected static final String JSON_KEY_TRANSFER_BILLABLE = "TRANSFER_BILLABLE";
	protected static final String JSON_KEY_TRANSFER_USED = "TRANSFER_USED";
	protected static final String JSON_KEY_TRANSFER_POOL = "TRANSFER_POOL";
	protected static final String JSON_KEY_ACTIVE_SINCE = "ACTIVE_SINCE";

	private final JSONObject jsonObject;

	protected List<ApiError> errors = new ArrayList<ApiError>();
	protected String action = null;

	public BaseResponse(JSONObject jsonObject) {
		this.jsonObject = jsonObject;
		parse(jsonObject, false);
	}

	public BaseResponse(JSONObject jsonObject, boolean ignoreErrorArray) {
		this.jsonObject = jsonObject;
		parse(jsonObject, true);
	}

	private void parse(JSONObject jsonObject, boolean ignoreErrorArray) {
		if(!ignoreErrorArray) {
			JSONArray errorArray = jsonObject.getJSONArray(JSON_KEY_ERRORARRAY);

			for (Object object : errorArray) {
				errors.add(new ApiError((JSONObject)object));
			}

			jsonObject.remove(JSON_KEY_ERRORARRAY);
		}

		this.action = jsonObject.getString(JSON_KEY_ACTION);
		jsonObject.remove(JSON_KEY_ACTION);
	}

	/**
	 * Read and remove String with key from JSON
	 *
	 * @param key the key to read as a string and remove
	 *
	 * @return the read key (or null if it doesn't exist)
	 */
	protected String readString(String key) {
		return this.readString(jsonObject, key);
	}

	/**
	 * Read and remove String with key from JSON object
	 *
	 * @param response The JSON object to read from
	 * @param key the key to read as a string and remove
	 *
	 * @return the read key (or null if it doesn't exist)
	 */
	protected String readString(JSONObject response, String key) {
		final Object value = response.remove(key);
		if (null == value || JSONObject.NULL == value) {
			LOGGER.warn("No field for key {}", key);
			return null;
		}
		return value.toString();
	}

	/**
	 * Read and remove int with key from JSON object
	 *
	 * @param key the key to read as an int and remove
	 *
	 * @return the read key (or -1 if it doesn't exist)
	 */
	protected int readInt(String key) {
		final Object value = jsonObject.remove(key);
		if (null == value || JSONObject.NULL == value) {
			LOGGER.warn("No field for key {}", key);
			return -1;
		}
		return value instanceof Number ? ((Number) value).intValue() : Integer.parseInt(value.toString());
	}

	/**
	 * Read and remove long with key from JSON object
	 *
	 * @param key the key to read as a long and remove
	 *
	 * @return the read key (or -1L if it doesn't exist)
	 */
	protected long readLong(String key) {
		final Object value = jsonObject.remove(key);
		if (null == value || JSONObject.NULL == value) {
			LOGGER.warn("No field for key {}", key);
			return -1L;
		}
		return value instanceof Number ? ((Number) value).longValue() : Long.parseLong(value.toString());
	}

	/**
	 * Read and remove JSONObject with key from JSON object
	 *
	 * @param key the key to read as a JSONObject and remove
	 *
	 * @return the read key (or null if it doesn't exist)
	 */
	protected JSONObject readObject(String key) {
		return this.readObject(jsonObject, key);
	}

	/**
	 * Read and remove JSONObject with key from JSON object
	 *
	 * @param response The JSON object to read from
	 * @param key the key to read as a JSONObject and remove
	 *
	 * @return the read key (or null if it doesn't exist)
	 */
	protected JSONObject readObject(JSONObject response, String key) {
		final Object value = response.remove(key);
		if (null == value || JSONObject.NULL == value) {
			LOGGER.warn("No field for key {}", key);
			return null;
		}
		return value instanceof JSONObject ? (JSONObject) value : null;
	}

	/**
	 * Read and remove JSONArray with key from JSON object
	 *
	 * @param key the key to read as a JSONArray and remove
	 *
	 * @return the read key (or null if it doesn't exist)
	 */
	protected JSONArray readObjects(String key) {
		final Object value = jsonObject.remove(key);
		if (null == value || JSONObject.NULL == value) {
			LOGGER.warn("No field for key {}", key);
			return null;
		}
		return value instanceof JSONArray ? (JSONArray) value : null;
	}

	/**
	 * Parse through the expected keys to determine whether any of the keys in
	 * the response will not be mapped.  This will loop through the JSON object
	 * and any key left in the object will generate a 'WARN' message.  The
	 * response class __MUST__ remove the object (i.e. jsonObject.remove(KEY_NAME))
	 * after getting the value, or use the utility methods in this class.  This
	 * is used more as a testing tool/sanity test than anything else as there
	 * are some instances in where keys are returned, however are not listed in
	 * the documentation.
	 *
	 * {@link BaseResponse#readInt(String)}
	 * {@link BaseResponse#readLong(String)}
	 * {@link BaseResponse#readString(String)}
	 * {@link BaseResponse#readObject(String)}
	 *
	 * @param LOGGER     The logger to use
	 */
	@SuppressWarnings("rawtypes")
	protected void warnOnMissedKeys(Logger LOGGER) {
		if (LOGGER.isWarnEnabled()) {
			Iterator keys = jsonObject.keys();
			while (keys.hasNext()) {
				String key = (String) keys.next();
				LOGGER.warn("Found an unexpected key of '{}' in JSON that is not mapped to a field.", key);
			}
		}
	}
	public String getAction() {
		return(this.action);
	}

	public boolean hasErrors() {
		return(!this.errors.isEmpty());
	}

	public List<ApiError> getErrors() {
		return(this.errors);
	}

}


text:
#import "NSObject.h"

@class NSAlert, NSArray, NSDictionary, NSError, NSString, PBXProject, PBXProjectDocument, XCInvocationQueue, XCRefactoringModule, XCRefactoringStart, XCRefactoringTransformation;

@interface XCRefactoring : NSObject
{
    PBXProjectDocument *_projectDocument;
    PBXProject *_project;
    XCInvocationQueue *_queue;
    XCRefactoringModule *_module;
    NSString *_nextFile;
    float _complete;
    NSString *_localizedTaskDescriptionString;
    int _taskProgressType;
    XCRefactoringTransformation *_currentTransformation;
    int _fileThreadInProgress;
    int _shouldStart;
    BOOL _subsequentFileThreadCanceled;
    NSDictionary *_initialInput;
    unsigned long long _fileChangeSetIndex;
    NSError *_applyingFileChangeSetsError;
    BOOL _currentFileChangeSetFinished;
    XCRefactoringStart *_waitingStart;
    NSAlert *_errorAlert;
    NSAlert *_discardChangesAlert;
    NSArray *_scmEditFilePaths;
    BOOL _cancelingCurrentSession;
}

+ (BOOL)canConvertToObjC2:(id)arg1;
+ (BOOL)canRefactorPerSelectionInTextView:(id)arg1;
+ (BOOL)_areAllBuildContextsAvailable:(id)arg1;
+ (BOOL)_isIndexingInProgress:(id)arg1;
- (void)dealloc;
- (id)initWithProjectDocument:(id)arg1 project:(id)arg2;
- (void)_finishSCMEditOperation:(id)arg1;
- (id)_makeSCMEditOperationError:(id)arg1;
- (BOOL)setData:(id)arg1 context:(void *)arg2 error:(id *)arg3;
- (BOOL)setString:(id)arg1 context:(void *)arg2 error:(id *)arg3;
- (BOOL)postApplyForExistingTextFileChangeSet:(id)arg1 context:(void *)arg2 error:(id *)arg3;
- (BOOL)preApplyForExistingTextFileChangeSet:(id)arg1 context:(void **)arg2 error:(id *)arg3;
- (void)displayError:(id)arg1;
- (id)dataForFilePath:(id)arg1;
- (id)project;
- (BOOL)previewWithSetUpModule:(id)arg1 transformKey:(id)arg2;
- (id)postInitialFileInfoForTransformKey:(id)arg1 error:(id *)arg2;
- (id)setUpInfoForTransformKey:(id)arg1 error:(id *)arg2;
- (void)applyCurrentTransformation;
- (void)cancelCurrentSessionDontCloseWindow;
- (void)cancelCurrentSession;
- (void)cancelCurrentTransformation;
- (void)convertToObjC2;
- (void)refactorWithFile:(id)arg1 lineInfo:(struct _XCRefactoringLineInfo)arg2 selectionValidator:(id)arg3;
- (void)_runProgressDialogWithTitle:(id)arg1 window:(id *)arg2 session:(struct _NSModalSession **)arg3;
- (BOOL)_handleUserInput:(id)arg1 transformKeyAndInvokeFileThread:(id)arg2 error:(id *)arg3;
- (void)_discardChangesAlertDidEnd:(id)arg1 returnCode:(long long)arg2 contextInfo:(void *)arg3;
- (void)_startRefactoring:(id)arg1;
- (void)_continueRefactoring:(id)arg1;
- (void)_createModule;
- (id)_editedFileContents;
- (void)_appliedChangesForFileChangeSet:(id)arg1 error:(id)arg2;
- (void)_invokeInitialFileThread;
- (void)_initialFileThread;
- (void)_initialFileThreadResult:(id)arg1;
- (void)_initialFileThreadShouldCancelSession:(id)arg1;
- (void)_initialFileThreadShouldCancelTransformation:(id)arg1;
- (void)_initialFileThreadShouldStartSubsequentFileThread:(id)arg1;
- (void)_initialFileThreadShouldStartNothing:(id)arg1;
- (void)_invokeSubsequentFileThread;
- (void)_subsequentFileThread;
- (void)_subsequentFileThreadResult:(id)arg1;
- (void)_subsequentFileThreadShouldCancelSession:(id)arg1;
- (void)_subsequentFileThreadShouldCancelTransformation:(id)arg1;
- (void)_subsequentFileThreadShouldStartSubsequentFileThread:(id)arg1;
- (void)_subsequentFileThreadShouldStartNothing:(id)arg1;
- (void)_releaseCurrentTransformation;
- (void)shouldCollectCurrentTransformation;
- (void)_updateWithInfoArray:(id)arg1;
- (void)_cancelCommonSteps;
- (void)_subsequentFileThreadPostResultCommonSteps;
- (id)_queue;
- (void)_stopActivityViewerTask;
- (void)_beginActivityViewerPreviewTask;
- (void)_startActivityViewerTask;
- (void)_beginActivityViewerIndeterminateTask;
- (void)_setTaskDescriptionString:(id)arg1;
- (void)_errorAlertDidEnd:(id)arg1 returnCode:(long long)arg2 contextInfo:(void *)arg3;
- (id)_localized:(id)arg1;
- (id)taskBadge;
- (id)taskDescriptionString;
- (id)taskDisplayString;
- (id)taskIdentifier;
- (BOOL)taskCanBeStoppedManually;
- (BOOL)taskRequiresIntervention;
- (BOOL)taskStopRunning;
- (int)taskProgressType;
- (float)taskPercentComplete;

@end


text:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="horizontal"
    android:weightSum="2">

    <View
        android:layout_width="0dp"
        android:layout_height="150dp"
        android:layout_weight="0.1"
        android:focusable="true"
        android:focusableInTouchMode="true"/>

    <LinearLayout
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_weight="0.85"
        android:orientation="vertical">

        <ImageView
            android:id="@+id/iv_gallery_1"
            android:layout_width="match_parent"
            android:layout_height="@dimen/gallery_image_height"
            android:layout_margin="10dp"
            android:background="?attr/selectableItemBackground"
            android:padding="10dp"
            android:scaleType="fitXY" />

        <EditText
            android:id="@+id/et_gallery_1"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:textAlignment="center"
            android:ems="10"
            android:inputType="textPersonName"
            android:text="@string/batch_gallery_author" />
    </LinearLayout>

    <View
        android:layout_width="0dp"
        android:layout_height="150dp"
        android:layout_weight="0.1" />

    <LinearLayout
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_weight="0.85"
        android:orientation="vertical">

        <ImageView
            android:id="@+id/iv_gallery_2"
            android:layout_width="match_parent"
            android:layout_height="@dimen/gallery_image_height"
            android:layout_margin="10dp"
            android:background="?attr/selectableItemBackground"
            android:padding="10dp"
            android:scaleType="fitXY" />

        <EditText
            android:id="@+id/et_gallery_2"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:textAlignment="center"
            android:ems="10"
            android:inputType="textPersonName"
            android:text="@string/batch_gallery_author" />
    </LinearLayout>

    <View
        android:layout_width="0dp"
        android:layout_height="150dp"
        android:layout_weight="0.1" />
</LinearLayout>


text:
class SS::Migration20210212000000
  include SS::Migration::Base

  depends_on "20201204000000"

  def change
    inquiry_permissions = %w(
      read_other_inquiry_columns
      read_private_inquiry_columns
      edit_other_inquiry_columns
      edit_private_inquiry_columns
      delete_other_inquiry_columns
      delete_private_inquiry_columns
      read_other_inquiry_answers
      read_private_inquiry_answers
      edit_other_inquiry_answers
      edit_private_inquiry_answers
      delete_other_inquiry_answers
      delete_private_inquiry_answers
    )
    ::Cms::Role.each do |role|
      next if role.created > Time.zone.parse("2021/02/12")
      role.add_to_set(permissions: inquiry_permissions)
    end
  end
end


text:
Burrow implements a number of transaction types. Transactions will be ordered by our consensus mechanism (Tendermint) and applied to our application state machine - replicated across all Burrow nodes. Each transaction is applied atomically and runs deterministically. The transactions contain the arguments for an [execution context](/execution/contexts).

Our transactions are defined in Protobuf [here](/protobuf/payload.proto).

Transactions can be built using our GRPC client libraries programmatically, via [burrow.js](/docs/js-api.md), or with`burrow deploy`, see our [deploying contracts guide](/docs/tutorials/3-deploy-contracts.md).

## [CallTx](https://godoc.org/github.com/hyperledger/burrow/txs/payload#CallTx)

Our core transaction type that calls EVM code, possibly transferring value. It takes the following parameters:

| Parameter | Type | Description |
| ----------|------|-------------|
| Input |
	Address *github_com_hyperledger_burrow_crypto.Address
	GasLimit uint64
	// Fee to offer validators for processing transaction
	Fee uint64 `protobuf:"varint,4,opt,name=Fee,proto3" json:"Fee,omitempty"`
	// EVM bytecode
	Data github_com_hyperledger_burrow_binary.HexBytes `protobuf:"bytes,5,opt,name=Data,proto3,customtype=github.com/hyperledger/burrow/binary.HexBytes" json:"Data"`
	// WASM bytecode
	WASM github_com_hyperledger_burrow_binary.HexBytes `protobuf:"bytes,6,opt,name=WASM,proto3,customtype=github.com/hyperledger/burrow/binary.HexBytes" json:"tags,omitempty"`
	// Set of contracts this code will deploy
	ContractMeta         []*ContractMeta `protobuf:"bytes,7,rep,name=ContractMeta,proto3" json:"ContractMeta,omitempty"`

## [SendTx](https://godoc.org/github.com/hyperledger/burrow/txs/payload#SendTx)

Allows [native token](/docs/reference/accounts.md) to be sent from multiple inputs to multiple outputs. The basic value transfer function that calls no EVM Code.

## [NameTx](https://godoc.org/github.com/hyperledger/burrow/txs/payload#NameTx)

Provides access to a global name registry service that associates a particular string key with a data payload and an owner. The control of the name is guaranteed for the period of the lease which is a determined by a fee.

Note: a future revision will change the way in which leases are calculated. Currently we use a somewhat historically-rooted fixed fee, see the [`NameCostPerBlock` function](/execution/names/names.go).

## [BondTx](https://godoc.org/github.com/hyperledger/burrow/txs/payload#BondTx)

This allows validators nominate themselves to the validator set by placing a bond subtracted from their balance.

## [UnbondTx](https://godoc.org/github.com/hyperledger/burrow/txs/payload#UnbondTx)

This allows validators remove themselves to the validator set returning their bond to their balance.

## [BatchTx](https://godoc.org/github.com/hyperledger/burrow/txs/payload#BatchTx)

Runs a set of transactions atomically in a single meta-transaction within a single block

## [GovTx](https://godoc.org/github.com/hyperledger/burrow/txs/payload#GovTx)

An all-powerful transaction for modifying existing accounts.

## [ProposalTx](https://godoc.org/github.com/hyperledger/burrow/txs/payload#ProposalTx)

A transaction type containing a batch of transactions on which a ballot is held to determine whether to execute, see [proposals tutorial](/docs/tutorials/8-proposals.md)

## [PermsTx](https://godoc.org/github.com/hyperledger/burrow/txs/payload#PermsTx)

A transaction to modify the permissions of accounts.