Immutable.java

/*
 * Copyright 2017 OmniFaces
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on
 * an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the
 * specific language governing permissions and limitations under the License.
 */
package org.omnifaces.util.concurrentlinkedhashmap;

import java.lang.annotation.Documented;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;

/**
 * The class to which this annotation is applied is immutable.  This means that
 * its state cannot be seen to change by callers, which implies that
 * <ul>
 * <li> all public fields are final, </li>
 * <li> all public final reference fields refer to other immutable objects, and </li>
 * <li> constructors and methods do not publish references to any internal state
 *      which is potentially mutable by the implementation. </li>
 * </ul>
 * Immutable objects may still have internal mutable state for purposes of performance
 * optimization; some state variables may be lazily computed, so long as they are computed
 * from immutable state and that callers cannot tell the difference.
 * <p>
 * Immutable objects are inherently thread-safe; they may be passed between threads or
 * published without synchronization.
 */
@Documented
@Target(ElementType.TYPE)
@Retention(RetentionPolicy.RUNTIME)
@interface Immutable {
	//
}