1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one or more
3 * contributor license agreements. See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * The ASF licenses this file to You under the Apache License, Version 2.0
6 * (the "License"); you may not use this file except in compliance with
7 * the License. You may obtain a copy of the License at
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17 package org.apache.commons.pool2.impl;
18
19 import org.apache.commons.pool2.PooledObject;
20
21 /**
22 * Provides the default implementation of {@link EvictionPolicy} used by the pools.
23 * <p>
24 * Objects will be evicted if the following conditions are met:
25 * </p>
26 * <ul>
27 * <li>The object has been idle longer than
28 * {@link GenericObjectPool#getMinEvictableIdleDuration()} /
29 * {@link GenericKeyedObjectPool#getMinEvictableIdleDuration()}</li>
30 * <li>There are more than {@link GenericObjectPool#getMinIdle()} /
31 * {@link GenericKeyedObjectPoolConfig#getMinIdlePerKey()} idle objects in
32 * the pool and the object has been idle for longer than
33 * {@link GenericObjectPool#getSoftMinEvictableIdleDuration()} /
34 * {@link GenericKeyedObjectPool#getSoftMinEvictableIdleDuration()}
35 * </ul>
36 * <p>
37 * This class is immutable and thread-safe.
38 * </p>
39 *
40 * @param <T> the type of objects in the pool.
41 * @since 2.0
42 */
43 public class DefaultEvictionPolicy<T> implements EvictionPolicy<T> {
44
45 /**
46 * Constructs a new instance.
47 */
48 public DefaultEvictionPolicy() {
49 // empty
50 }
51
52 @Override
53 public boolean evict(final EvictionConfig config, final PooledObject<T> underTest, final int idleCount) {
54 // @formatter:off
55 return config.getIdleSoftEvictDuration().compareTo(underTest.getIdleDuration()) < 0 &&
56 config.getMinIdle() < idleCount ||
57 config.getIdleEvictDuration().compareTo(underTest.getIdleDuration()) < 0;
58 // @formatter:on
59 }
60 }