/*
* @(#)ConcurrentModificationException.java 1.20 06/03/30
*
* Copyright 2006 Sun Microsystems, Inc. All rights reserved.
* SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
*/
package java.util;
/**
* This exception may be thrown by methods that have detected concurrent
* modification of an object when such modification is not permissible.
* <p>
* For example, it is not generally permissible for one thread to modify a Collection
* while another thread is iterating over it. In general, the results of the
* iteration are undefined under these circumstances. Some Iterator
* implementations (including those of all the general purpose collection implementations
* provided by the JRE) may choose to throw this exception if this behavior is
* detected. Iterators that do this are known as <i>fail-fast</i> iterators,
* as they fail quickly and cleanly, rather that risking arbitrary,
* non-deterministic behavior at an undetermined time in the future.
* <p>
* Note that this exception does not always indicate that an object has
* been concurrently modified by a <i>different</i> thread. If a single
* thread issues a sequence of method invocations that violates the
* contract of an object, the object may throw this exception. For
* example, if a thread modifies a collection directly while it is
* iterating over the collection with a fail-fast iterator, the iterator
* will throw this exception.
*
* <p>Note that fail-fast behavior cannot be guaranteed as it is, generally
* speaking, impossible to make any hard guarantees in the presence of
* unsynchronized concurrent modification. Fail-fast operations
* throw <tt>ConcurrentModificationException</tt> on a best-effort basis.
* Therefore, it would be wrong to write a program that depended on this
* exception for its correctness: <i><tt>ConcurrentModificationException</tt>
* should be used only to detect bugs.</i>
*
* @author Josh Bloch
* @version 1.20, 03/30/06
* @see Collection
* @see Iterator
* @see ListIterator
* @see Vector
* @see LinkedList
* @see HashSet
* @see Hashtable
* @see TreeMap
* @see AbstractList
* @since 1.2
*/
public class ConcurrentModificationException extends RuntimeException {
/**
* Constructs a ConcurrentModificationException with no
* detail message.
*/
public ConcurrentModificationException() {
}
/**
* Constructs a <tt>ConcurrentModificationException</tt> with the
* specified detail message.
*
* @param message the detail message pertaining to this exception.
*/
public ConcurrentModificationException(String message) {
super(message);
}
}