java.util.ConcurrentModificationException Maven / Gradle / Ivy
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package java.util;
/**
* This exception may be thrown by methods that have detected concurrent
* modification of an object when such modification is not permissible.
*
* 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 fail-fast iterators,
* as they fail quickly and cleanly, rather that risking arbitrary,
* non-deterministic behavior at an undetermined time in the future.
*
* Note that this exception does not always indicate that an object has
* been concurrently modified by a different 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.
*
*
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 {@code ConcurrentModificationException} on a best-effort basis.
* Therefore, it would be wrong to write a program that depended on this
* exception for its correctness: {@code ConcurrentModificationException}
* should be used only to detect bugs.
*
* @author Josh Bloch
* @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 {
private static final long serialVersionUID = -3666751008965953603L;
/**
* Constructs a ConcurrentModificationException with no
* detail message.
*/
public ConcurrentModificationException() {
}
/**
* Constructs a {@code ConcurrentModificationException} with the
* specified detail message.
*
* @param message the detail message pertaining to this exception.
*/
public ConcurrentModificationException(String message) {
super(message);
}
/**
* Constructs a new exception with the specified cause and a detail
* message of {@code (cause==null ? null : cause.toString())} (which
* typically contains the class and detail message of {@code cause}.
*
* @param cause the cause (which is saved for later retrieval by the
* {@link Throwable#getCause()} method). (A {@code null} value is
* permitted, and indicates that the cause is nonexistent or
* unknown.)
* @since 1.7
*/
public ConcurrentModificationException(Throwable cause) {
super(cause);
}
/**
* Constructs a new exception with the specified detail message and
* cause.
*
*
Note that the detail message associated with cause is
* not automatically incorporated in this exception's detail
* message.
*
* @param message the detail message (which is saved for later retrieval
* by the {@link Throwable#getMessage()} method).
* @param cause the cause (which is saved for later retrieval by the
* {@link Throwable#getCause()} method). (A {@code null} value
* is permitted, and indicates that the cause is nonexistent or
* unknown.)
* @since 1.7
*/
public ConcurrentModificationException(String message, Throwable cause) {
super(message, cause);
}
}