/*******************************************************************************
*
* Copyright (c) 2004-2009 Oracle Corporation.
*
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
*
* Kohsuke Kawaguchi
*
*
*******************************************************************************/
package hudson;
import java.lang.annotation.Documented;
import static java.lang.annotation.ElementType.FIELD;
import java.lang.annotation.Retention;
import static java.lang.annotation.RetentionPolicy.SOURCE;
import java.lang.annotation.Target;
/**
* Represents fields that are protected for concurrency by the copy-on-write
* semantics.
*
* <p> Fields marked by this annotation always holds on to an immutable
* collection. A change to the collection must be done by first creating a new
* collection object, making changes, then replacing the reference atomically.
*
* <p> This allows code to access the field without synchronization, and greatly
* reduces the risk of dead-lock bugs.
*
* <p> The field marked with this annotation usually needs to be marked as
* <tt>volatile</tt>.
*
* @author Kohsuke Kawaguchi
*/
@Retention(SOURCE)
@Documented
@Target(FIELD)
public @interface CopyOnWrite {
}