1 /* 2 * ModeShape (http://www.modeshape.org) 3 * See the COPYRIGHT.txt file distributed with this work for information 4 * regarding copyright ownership. Some portions may be licensed 5 * to Red Hat, Inc. under one or more contributor license agreements. 6 * See the AUTHORS.txt file in the distribution for a full listing of 7 * individual contributors. 8 * 9 * ModeShape is free software. Unless otherwise indicated, all code in ModeShape 10 * is licensed to you under the terms of the GNU Lesser General Public License as 11 * published by the Free Software Foundation; either version 2.1 of 12 * the License, or (at your option) any later version. 13 * 14 * ModeShape is distributed in the hope that it will be useful, 15 * but WITHOUT ANY WARRANTY; without even the implied warranty of 16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 17 * Lesser General Public License for more details. 18 * 19 * You should have received a copy of the GNU Lesser General Public 20 * License along with this software; if not, write to the Free 21 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 22 * 02110-1301 USA, or see the FSF site: http://www.fsf.org. 23 */ 24 package org.modeshape.graph.cache; 25 26 import java.util.concurrent.TimeUnit; 27 import net.jcip.annotations.NotThreadSafe; 28 import org.modeshape.common.util.CheckArg; 29 30 /** 31 * A basic mutable {@link CachePolicy} implementation. 32 */ 33 @NotThreadSafe 34 public class BasicCachePolicy implements CachePolicy { 35 36 private static final long serialVersionUID = 1L; 37 private long timeToLiveInMillis = 0L; 38 39 public BasicCachePolicy() { 40 } 41 42 public BasicCachePolicy( long timeToCache, 43 TimeUnit unit ) { 44 CheckArg.isNotNull(unit, "unit"); 45 this.timeToLiveInMillis = TimeUnit.MILLISECONDS.convert(timeToCache, unit); 46 } 47 48 /** 49 * {@inheritDoc} 50 * 51 * @see org.modeshape.graph.cache.CachePolicy#getTimeToLive() 52 */ 53 public long getTimeToLive() { 54 return this.timeToLiveInMillis; 55 } 56 57 /** 58 * Set the time for values and information to live in the cache. 59 * 60 * @param timeToLive Sets timeToLive to the specified value. 61 * @param unit the unit in which the time to live value is defined 62 */ 63 public void setTimeToLive( long timeToLive, 64 TimeUnit unit ) { 65 this.timeToLiveInMillis = TimeUnit.NANOSECONDS.convert(timeToLive, unit); 66 } 67 68 public boolean isEmpty() { 69 return this.timeToLiveInMillis == 0; 70 } 71 72 public CachePolicy getUnmodifiable() { 73 return new ImmutableCachePolicy(this.getTimeToLive()); 74 } 75 76 /** 77 * {@inheritDoc} 78 * 79 * @see java.lang.Object#equals(java.lang.Object) 80 */ 81 @Override 82 public boolean equals( Object obj ) { 83 if (obj == this) return true; 84 if (obj instanceof CachePolicy) { 85 CachePolicy that = (CachePolicy)obj; 86 if (this.getTimeToLive() != that.getTimeToLive()) return false; 87 if (obj instanceof BasicCachePolicy) return true; 88 } 89 return false; 90 } 91 92 /** 93 * {@inheritDoc} 94 * 95 * @see java.lang.Object#toString() 96 */ 97 @Override 98 public String toString() { 99 return "{ TTL=" + this.timeToLiveInMillis + " ms }"; 100 } 101 102 }