javax.cache.expiry.ModifiedExpiryPolicy Maven / Gradle / Ivy
/**
* Copyright 2011-2016 Terracotta, Inc.
* Copyright 2011-2016 Oracle America Incorporated
*
* 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 javax.cache.expiry;
import javax.cache.configuration.Factory;
import javax.cache.configuration.FactoryBuilder;
import java.io.Serializable;
/**
* An {@link ExpiryPolicy} that defines the expiry {@link Duration}
* of a Cache Entry based on the last time it was updated. Updating
* includes created and changing (updating) an entry.
*
* @author Greg Luck
* @author Brian Oliver
* @since 1.0
* @see ExpiryPolicy
*/
public final class ModifiedExpiryPolicy implements ExpiryPolicy, Serializable {
/**
* The serialVersionUID required for {@link java.io.Serializable}.
*/
public static final long serialVersionUID = 201305101602L;
/**
* The {@link Duration} a Cache Entry should be available before it expires.
*/
private Duration expiryDuration;
/**
* Constructs an {@link ModifiedExpiryPolicy} {@link ExpiryPolicy}.
*
* @param expiryDuration the {@link Duration} a Cache Entry should exist be
* before it expires after being modified
*/
public ModifiedExpiryPolicy(Duration expiryDuration) {
this.expiryDuration = expiryDuration;
}
/**
* Obtains a {@link Factory} for a Modified {@link ExpiryPolicy}.
*
* @param duration The expiry duration
* @return a {@link Factory} for a Modified {@link ExpiryPolicy}.
*/
public static Factory factoryOf(Duration duration) {
return new FactoryBuilder.SingletonFactory(new ModifiedExpiryPolicy(duration));
}
/**
* {@inheritDoc}
*/
@Override
public Duration getExpiryForCreation() {
//for newly created entries we use the specified expiry duration
return expiryDuration; }
/**
* {@inheritDoc}
*/
@Override
public Duration getExpiryForAccess() {
//accessing a cache entry has no affect on the current expiry duration
return null;
}
/**
* {@inheritDoc}
*/
@Override
public Duration getExpiryForUpdate() {
//when a cache entry is modified, we return the specified expiry duration,
//ignoring the current expiry duration
return expiryDuration;
}
/**
* {@inheritDoc}
*/
@Override
public int hashCode() {
final int prime = 31;
int result = 1;
result = prime * result + ((expiryDuration == null) ? 0 : expiryDuration.hashCode());
return result;
}
/**
* {@inheritDoc}
*/
@Override
public boolean equals(Object object) {
if (this == object) {
return true;
}
if (object == null) {
return false;
}
if (!(object instanceof ModifiedExpiryPolicy)) {
return false;
}
ModifiedExpiryPolicy other = (ModifiedExpiryPolicy) object;
if (expiryDuration == null) {
if (other.expiryDuration != null) {
return false;
}
} else if (!expiryDuration.equals(other.expiryDuration)) {
return false;
}
return true;
}
}