/*
* Copyright 2002-2015 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.cache.support;
import java.io.Serializable;
/**
* Simple serializable class that serves as a {@code null} replacement
* for cache stores which otherwise do not support {@code null} values.
*
* @author Juergen Hoeller
* @since 4.2.2
* @see AbstractValueAdaptingCache
*/
public final class NullValue implements Serializable {
static final Object INSTANCE = new NullValue();
private static final long serialVersionUID = 1L;
private NullValue() {
}
private Object readResolve() {
return INSTANCE;
}
}