gt:                 return newInstance(factoryClassName, classLoader);
context: /*
   * Licensed to the Apache Software Foundation (ASF) under one or more
   * contributor license agreements.  See the NOTICE file distributed with
   * this work for additional information regarding copyright ownership.
   * The ASF licenses this file to You under the Apache License, Version 2.0
   * (the "License"); you may not use this file except in compliance with
   * the License.  You may obtain a copy of the License at
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  // $Id: FactoryFinder.java 670432 2008-06-23 02:02:08Z mrglavas $
  
  package javax.xml.datatype;
  
  import java.io.BufferedReader;
  import java.io.File;
  import java.io.FileInputStream;
  import java.io.IOException;
  import java.io.InputStream;
  import java.io.InputStreamReader;
  import java.net.URL;
  import java.util.Properties;
  import libcore.io.IoUtils;
  
  /**
   * <p>Implement pluggable data types.</p>
   *
   * <p>This class is duplicated for each JAXP subpackage so keep it in
   * sync.  It is package private for secure class loading.</p>
   *
   * @author <a href="mailto:Jeff.Suttor@Sun.com">Jeff Suttor</a>
   * @version $Revision: 670432 $, $Date: 2008-06-22 19:02:08 -0700 (Sun, 22 Jun 2008) $
   * @since 1.5
   */
  final class FactoryFinder {
  
      /** <p>Name of class to display in output messages.</p> */
      private static final String CLASS_NAME = "javax.xml.datatype.FactoryFinder";
  
      /** <p>Debug flag to trace loading process.</p> */
      private static boolean debug = false;
  
      /**
       * <p>Cache properties for performance. Use a static class to avoid double-checked
       * locking.</p>
       */
      private static class CacheHolder {
  
          private static Properties cacheProps = new Properties();
  
          static {
              String javah = System.getProperty("java.home");
              String configFile = javah + File.separator + "lib" + File.separator + "jaxp.properties";
              File f = new File(configFile);
              if (f.exists()) {
                  if (debug) debugPrintln("Read properties file " + f);
                  try {
                      cacheProps.load(new FileInputStream(f));
                  } catch (Exception ex) {
                      if (debug) {
                          ex.printStackTrace();
                      }
                  }
              }
          }
      }
  
      /** Default columns per line. */
      private static final int DEFAULT_LINE_LENGTH = 80;
  
      /**
       * <p>Check to see if debugging enabled by property.</p>
       *
       * <p>Use try/catch block to support applets, which throws
       * SecurityException out of this code.</p>
       */
      static {
          String val = System.getProperty("jaxp.debug");
          // Allow simply setting the prop to turn on debug
          debug = val != null && (! "false".equals(val));
      }
  
      private FactoryFinder() {}
  
      /**
       * <p>Output debugging messages.</p>
       *
       * @param msg <code>String</code> to print to <code>stderr</code>.
       */
      private static void debugPrintln(String msg) {
          if (debug) {
              System.err.println(
                  CLASS_NAME
                  + ":"
                  + msg);
          }
      }
  
      /**
       * <p>Find the appropriate <code>ClassLoader</code> to use.</p>
       *
       * <p>The context ClassLoader is preferred.</p>
       *
       * @return <code>ClassLoader</code> to use.
       *
       * @throws ConfigurationError If a valid <code>ClassLoader</code> cannot be identified.
       */
      private static ClassLoader findClassLoader() throws ConfigurationError {
          // Figure out which ClassLoader to use for loading the provider
          // class.  If there is a Context ClassLoader then use it.
  
          ClassLoader classLoader = Thread.currentThread().getContextClassLoader();
  
          if (debug) debugPrintln(
              "Using context class loader: "
              + classLoader);
  
          if (classLoader == null) {
              // if we have no Context ClassLoader
              // so use the current ClassLoader
              classLoader = FactoryFinder.class.getClassLoader();
              if (debug) debugPrintln(
                  "Using the class loader of FactoryFinder: "
                  + classLoader);
          }
  
          return classLoader;
      }
  
      /**
       * <p>Create an instance of a class using the specified ClassLoader.</p>
       *
       * @param className Name of class to create.
       * @param classLoader ClassLoader to use to create named class.
       *
       * @return New instance of specified class created using the specified ClassLoader.
       *
       * @throws ConfigurationError If class could not be created.
       */
      static Object newInstance(
          String className,
          ClassLoader classLoader)
          throws ConfigurationError {
  
          try {
              Class spiClass;
              if (classLoader == null) {
                  spiClass = Class.forName(className);
              } else {
                  spiClass = classLoader.loadClass(className);
              }
  
              if (debug) {
                  debugPrintln("Loaded " + className + " from " + which(spiClass));
              }
  
              return spiClass.newInstance();
          } catch (ClassNotFoundException x) {
              throw new ConfigurationError(
                  "Provider " + className + " not found", x);
          } catch (Exception x) {
              throw new ConfigurationError(
                  "Provider " + className + " could not be instantiated: " + x, x);
          }
      }
  
      /**
       * Finds the implementation Class object in the specified order.  Main
       * entry point.
       * Package private so this code can be shared.
       *
       * @param factoryId Name of the factory to find, same as a property name
       * @param fallbackClassName Implementation class name, if nothing else is found.  Use null to mean no fallback.
       *
       * @return Class Object of factory, never null
       *
       * @throws ConfigurationError If Class cannot be found.
       */
      static Object find(String factoryId, String fallbackClassName) throws ConfigurationError {
  
          ClassLoader classLoader = findClassLoader();
  
          // Use the system property first
          String systemProp = System.getProperty(factoryId);
          if (systemProp != null && systemProp.length() > 0) {
              if (debug) debugPrintln("found " + systemProp + " in the system property " + factoryId);
              return newInstance(systemProp, classLoader);
          }
  
          // try to read from $java.home/lib/jaxp.properties
          try {
              String factoryClassName = CacheHolder.cacheProps.getProperty(factoryId);
              if (debug) debugPrintln("found " + factoryClassName + " in $java.home/jaxp.properties");
  
              if (factoryClassName != null) {
  