java.util

Class ConcurrentModificationExceptio- n

Contents
  • All Implemented Interfaces:
    Serializable
    Direct Known Subclasses:
    DirectoryIteratorException

    public class ConcurrentModificationException
extends RuntimeException
    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 ConcurrentModificationException on a best-effort basis. Therefore, it would be wrong to write a program that depended on this exception for its correctness: ConcurrentModificationException should be used only to detect bugs.

    Since:
    1.2
    See Also:
    Collection, Iterator, ListIterator, Vector, LinkedList, HashSet, Hashtable, TreeMap, AbstractList, Serialized Form

    • Constructor Detail

      • ConcurrentModificationException

        public ConcurrentModificationException()
        Constructs a ConcurrentModificationException with no detail message.

      • ConcurrentModificationException

        public ConcurrentModificationException(String message)
        Constructs a ConcurrentModificationException with the specified detail message.
        Parameters:
        message - the detail message pertaining to this exception.

      • ConcurrentModificationException

        public ConcurrentModificationException(Throwable cause)
        Constructs a new exception with the specified cause and a detail message of (cause==null ? null : cause.toString()) (which typically contains the class and detail message of cause.
        Parameters:
        cause - the cause (which is saved for later retrieval by the Throwable.getCause() method). (A null value is permitted, and indicates that the cause is nonexistent or unknown.)
        Since:
        1.7

      • ConcurrentModificationException

        public ConcurrentModificationException(String message,
                               Throwable 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.

        Parameters:
        message - the detail message (which is saved for later retrieval by the Throwable.getMessage() method).
        cause - the cause (which is saved for later retrieval by the Throwable.getCause() method). (A null value is permitted, and indicates that the cause is nonexistent or unknown.)
        Since:
        1.7

Document created the 11/06/2005, last modified the 04/03/2020
Source of the printed document:https://www.gaudry.be/en/java-api-rf-java/util/ConcurrentModificationException.html

The infobrol is a personal site whose content is my sole responsibility. The text is available under CreativeCommons license (BY-NC-SA). More info on the terms of use and the author.

References

  1. View the html document Language of the document:fr Manuel PHP : https://docs.oracle.com

These references and links indicate documents consulted during the writing of this page, or which may provide additional information, but the authors of these sources can not be held responsible for the content of this page.
The author This site is solely responsible for the way in which the various concepts, and the freedoms that are taken with the reference works, are presented here. Remember that you must cross multiple source information to reduce the risk of errors.

Contents Haut