gt: 			throwable = ExceptionUtils.getCause( throwable );
context: /* ====================================================================
   * The Apache Software License, Version 1.1
   *
   * Copyright (c) 2002-2003 The Apache Software Foundation.  All rights
   * reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   *
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   *
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in
   *    the documentation and/or other materials provided with the
   *    distribution.
   *
   * 3. The end-user documentation included with the redistribution, if
   *    any, must include the following acknowledgement:
   *       "This product includes software developed by the
   *        Apache Software Foundation (http://www.apache.org/)."
   *    Alternately, this acknowledgement may appear in the software itself,
   *    if and wherever such third-party acknowledgements normally appear.
   *
   * 4. The names "The Jakarta Project", "Commons", and "Apache Software
   *    Foundation" must not be used to endorse or promote products derived
   *    from this software without prior written permission. For written
   *    permission, please contact apache@apache.org.
   *
   * 5. Products derived from this software may not be called "Apache"
   *    nor may "Apache" appear in their names without prior written
   *    permission of the Apache Software Foundation.
   *
   * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
   * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
   * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
   * DISCLAIMED.  IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
   * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
   * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
   * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
   * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
   * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
   * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
   * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   * SUCH DAMAGE.
   * ====================================================================
   *
   * This software consists of voluntary contributions made by many
   * individuals on behalf of the Apache Software Foundation.  For more
   * information on the Apache Software Foundation, please see
   * <http://www.apache.org/>.
   */
  package org.hibernate.exception;
  
  import java.io.PrintStream;
  import java.io.PrintWriter;
  import java.io.Serializable;
  import java.io.StringWriter;
  import java.util.ArrayList;
  import java.util.Arrays;
  import java.util.Collections;
  import java.util.Iterator;
  import java.util.List;
  
  /**
   * <p>A shared implementation of the nestable exception functionality.</p>
   * <p/>
   * The code is shared between
   * {@link org.apache.commons.lang.exception.NestableError NestableError},
   * {@link org.apache.commons.lang.exception.NestableException NestableException} and
   * {@link org.apache.commons.lang.exception.NestableRuntimeException NestableRuntimeException}.
   * </p>
   *
   * @author <a href="mailto:Rafal.Krzewski@e-point.pl">Rafal Krzewski</a>
   * @author <a href="mailto:dlr@collab.net">Daniel Rall</a>
   * @author <a href="mailto:knielsen@apache.org">Kasper Nielsen</a>
   * @author <a href="mailto:steven@caswell.name">Steven Caswell</a>
   * @author Sean C. Sullivan
   * @author Stephen Colebourne
   * @version $Id: NestableDelegate.java 4782 2004-11-21 00:11:27Z pgmjsd $
   * @since 1.0
   */
  public class NestableDelegate implements Serializable {
  
  	/**
  	 * Constructor error message.
  	 */
  	private static final String MUST_BE_THROWABLE =
  			"The Nestable implementation passed to the NestableDelegate(Nestable) "
  			+ "constructor must extend java.lang.Throwable";
  
  	/**
  	 * Holds the reference to the exception or error that we're
  	 * wrapping (which must be a {@link
  	 * org.apache.commons.lang.exception.Nestable} implementation).
  	 */
  	private Throwable nestable = null;
  
  	/**
  	 * Whether to print the stack trace top-down.
  	 * This public flag may be set by calling code, typically in initialisation.
  	 *
  	 * @since 2.0
  	 */
  	private static boolean topDown = true;
  
  	/**
  	 * Whether to trim the repeated stack trace.
  	 * This public flag may be set by calling code, typically in initialisation.
  	 *
  	 * @since 2.0
  	 */
  	private static boolean trimStackFrames = true;
  
  	/**
  	 * Constructs a new <code>NestableDelegate</code> instance to manage the
  	 * specified <code>Nestable</code>.
  	 *
  	 * @param nestable the Nestable implementation (<i>must</i> extend
  	 *                 {@link java.lang.Throwable})
  	 * @since 2.0
  	 */
  	public NestableDelegate(Nestable nestable) {
  		if ( nestable instanceof Throwable ) {
  			this.nestable = ( Throwable ) nestable;
  		}
  		else {
  			throw new IllegalArgumentException( MUST_BE_THROWABLE );
  		}
  	}
  
  	/**
  	 * Returns the error message of the <code>Throwable</code> in the chain
  	 * of <code>Throwable</code>s at the specified index, numbererd from 0.
  	 *
  	 * @param index the index of the <code>Throwable</code> in the chain of
  	 *              <code>Throwable</code>s
  	 * @return the error message, or null if the <code>Throwable</code> at the
  	 *         specified index in the chain does not contain a message
  	 * @throws IndexOutOfBoundsException if the <code>index</code> argument is
  	 *                                   negative or not less than the count of <code>Throwable</code>s in the
  	 *                                   chain
  	 * @since 2.0
  	 */
  	public String getMessage(int index) {
  		Throwable t = this.getThrowable( index );
  		if ( Nestable.class.isInstance( t ) ) {
  			return ( ( Nestable ) t ).getMessage( 0 );
  		}
  		else {
  			return t.getMessage();
  		}
  	}
  
  	/**
  	 * Returns the full message contained by the <code>Nestable</code>
  	 * and any nested <code>Throwable</code>s.
  	 *
  	 * @param baseMsg the base message to use when creating the full
  	 *                message. Should be generally be called via
  	 *                <code>nestableHelper.getMessage( super.getMessage() )</code>,
  	 *                where <code>super</code> is an instance of {@link
  	 *                java.lang.Throwable}.
  	 * @return The concatenated message for this and all nested
  	 *         <code>Throwable</code>s
  	 * @since 2.0
  	 */
  	public String getMessage(String baseMsg) {
  		StringBuffer msg = new StringBuffer();
  		if ( baseMsg != null ) {
  			msg.append( baseMsg );
  		}
  
  		Throwable nestedCause = ExceptionUtils.getCause( this.nestable );
  		if ( nestedCause != null ) {
  			String causeMsg = nestedCause.getMessage();
  			if ( causeMsg != null ) {
  				if ( baseMsg != null ) {
  					msg.append( ": " );
  				}
  				msg.append( causeMsg );
  			}
  
  		}
  		return ( msg.length() > 0 ? msg.toString() : null );
  	}
  
  	/**
  	 * Returns the error message of this and any nested <code>Throwable</code>s
  	 * in an array of Strings, one element for each message. Any
  	 * <code>Throwable</code> not containing a message is represented in the
  	 * array by a null. This has the effect of cause the length of the returned
  	 * array to be equal to the result of the {@link #getThrowableCount()}
  	 * operation.
  	 *
  	 * @return the error messages
  	 * @since 2.0
  	 */
  	public String[] getMessages() {
  		Throwable[] throwables = this.getThrowables();
  		String[] msgs = new String[throwables.length];
  		for ( int i = 0; i < throwables.length; i++ ) {
  			msgs[i] = Nestable.class.isInstance( throwables[i] ) ?
  					( ( Nestable ) throwables[i] ).getMessage( 0 ) :
  					throwables[i].getMessage();
  		}
  		return msgs;
  	}
  
  	/**
  	 * Returns the <code>Throwable</code> in the chain of
  	 * <code>Throwable</code>s at the specified index, numbererd from 0.
  	 *
  	 * @param index the index, numbered from 0, of the <code>Throwable</code> in
  	 *              the chain of <code>Throwable</code>s
  	 * @return the <code>Throwable</code>
  	 * @throws IndexOutOfBoundsException if the <code>index</code> argument is
  	 *                                   negative or not less than the count of <code>Throwable</code>s in the
  	 *                                   chain
  	 * @since 2.0
  	 */
  	public Throwable getThrowable(int index) {
  		if ( index == 0 ) {
  			return this.nestable;
  		}
  		Throwable[] throwables = this.getThrowables();
  		return throwables[index];
  	}
  
  	/**
  	 * Returns the number of <code>Throwable</code>s contained in the
  	 * <code>Nestable</code> contained by this delegate.
  	 *
  	 * @return the throwable count
  	 * @since 2.0
  	 */
  	public int getThrowableCount() {
  		return ExceptionUtils.getThrowableCount( this.nestable );
  	}
  
  	/**
  	 * Returns this delegate's <code>Nestable</code> and any nested
  	 * <code>Throwable</code>s in an array of <code>Throwable</code>s, one
  	 * element for each <code>Throwable</code>.
  	 *
  	 * @return the <code>Throwable</code>s
  	 * @since 2.0
  	 */
  	public Throwable[] getThrowables() {
  		return ExceptionUtils.getThrowables( this.nestable );
  	}
  
  	/**
  	 * Returns the index, numbered from 0, of the first <code>Throwable</code>
  	 * that matches the specified type in the chain of <code>Throwable</code>s
  	 * held in this delegate's <code>Nestable</code> with an index greater than
  	 * or equal to the specified index, or -1 if the type is not found.
  	 *
  	 * @param type      <code>Class</code> to be found
  	 * @param fromIndex the index, numbered from 0, of the starting position in
  	 *                  the chain to be searched
  	 * @return index of the first occurrence of the type in the chain, or -1 if
  	 *         the type is not found
  	 * @throws IndexOutOfBoundsException if the <code>fromIndex</code> argument
  	 *                                   is negative or not less than the count of <code>Throwable</code>s in the
  	 *                                   chain
  	 * @since 2.0
  	 */
  	public int indexOfThrowable(Class type, int fromIndex) {
  		if ( fromIndex < 0 ) {
  			throw new IndexOutOfBoundsException( "The start index was out of bounds: " + fromIndex );
  		}
  		Throwable[] throwables = ExceptionUtils.getThrowables( this.nestable );
  		if ( fromIndex >= throwables.length ) {
  			throw new IndexOutOfBoundsException( "The start index was out of bounds: "
  					+ fromIndex + " >= " + throwables.length );
  		}
  		for ( int i = fromIndex; i < throwables.length; i++ ) {
  			if ( throwables[i].getClass().equals( type ) ) {
  				return i;
  			}
  		}
  		return -1;
  	}
  
  	/**
  	 * Prints the stack trace of this exception the the standar error
  	 * stream.
  	 */
  	public void printStackTrace() {
  		printStackTrace( System.err );
  	}
  
  	/**
  	 * Prints the stack trace of this exception to the specified
  	 * stream.
  	 *
  	 * @param out <code>PrintStream</code> to use for output.
  	 * @see #printStackTrace(PrintWriter)
  	 */
  	public void printStackTrace(PrintStream out) {
  		synchronized ( out ) {
  			PrintWriter pw = new PrintWriter( out, false );
  			printStackTrace( pw );
  			// Flush the PrintWriter before it's GC'ed.
  			pw.flush();
  		}
  	}
  
  	/**
  	 * Prints the stack trace of this exception to the specified
  	 * writer. If the Throwable class has a <code>getCause</code>
  	 * method (i.e. running on jre1.4 or higher), this method just
  	 * uses Throwable's printStackTrace() method. Otherwise, generates
  	 * the stack-trace, by taking into account the 'topDown' and
  	 * 'trimStackFrames' parameters. The topDown and trimStackFrames
  	 * are set to 'true' by default (produces jre1.4-like stack trace).
  	 *
  	 * @param out <code>PrintWriter</code> to use for output.
  	 */
  	public void printStackTrace(PrintWriter out) {
  		Throwable throwable = this.nestable;
  		// if running on jre1.4 or higher, use default printStackTrace
  		if ( ExceptionUtils.isThrowableNested() ) {
  			if ( throwable instanceof Nestable ) {
  				( ( Nestable ) throwable ).printPartialStackTrace( out );
  			}
  			else {
  				throwable.printStackTrace( out );
  			}
  			return;
  		}
  
  		// generating the nested stack trace
  		List stacks = new ArrayList();
  		while ( throwable != null ) {
  			String[] st = getStackFrames( throwable );
  			stacks.add( st );
  