org.springframework.webflow.conversation.impl.NoOpConversationLock Maven / Gradle / Ivy
/*
* Copyright 2002-2006 the original author or authors.
*
* 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.springframework.webflow.conversation.impl;
import java.io.ObjectStreamException;
import java.io.Serializable;
/**
* A singleton lock that doesn't do anything. For use when conversations don't
* require or choose not to implement locking.
*
* @author Keith Donald
*/
class NoOpConversationLock implements ConversationLock, Serializable {
/**
* The singleton instance.
*/
public static final NoOpConversationLock INSTANCE = new NoOpConversationLock();
/**
* Private constructor to avoid instantiation.
*/
private NoOpConversationLock() {
}
public void lock() {
// no-op
}
public void unlock() {
// no-op
}
// resolve the singleton instance
private Object readResolve() throws ObjectStreamException {
return INSTANCE;
}
}