testsoftrefoutofmemory.java

Apache的通用池Jar包

/*
 * Copyright 1999-2004 The Apache Software Foundation.
 * 
 * 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.apache.commons.pool.impl;

import junit.framework.TestCase;
import junit.framework.TestSuite;

import org.apache.commons.pool.PoolableObjectFactory;

import java.util.Arrays;
import java.util.HashMap;

/**
 * @author Dirk Verbeeck
 * @version $Revision: 1.1 $ $Date: 2004/05/13 20:13:25 $
 */
public class TestSoftRefOutOfMemory extends TestCase {
    private SoftReferenceObjectPool pool;

    public TestSoftRefOutOfMemory(String testName) {
        super(testName);
    }

    public static TestSuite suite() {
        return new TestSuite(TestSoftRefOutOfMemory.class);
    }

    public void tearDown() throws Exception {
        if (pool != null) {
            pool.close();
            pool = null;
        }
        System.gc();
    }

    public void testOutOfMemory() throws Exception {
        pool = new SoftReferenceObjectPool(new SmallPoolableObjectFactory());

        Object obj = pool.borrowObject();
        assertEquals("1", obj);
        pool.returnObject(obj);
        obj = null;
        
        assertEquals(1, pool.getNumIdle());

        try {
            HashMap map = new HashMap();

            for (int i = 0; i < 1000000; i++) {
                map.put(new Integer(i), new String("Fred Flintstone" + i));
            }
        } catch (OutOfMemoryError ex) {
            
        }
        obj = pool.borrowObject();
        assertEquals("2", obj);
        pool.returnObject(obj);
        obj = null;
            
        assertEquals(1, pool.getNumIdle());
    }

    public void testOutOfMemory1000() throws Exception {
        pool = new SoftReferenceObjectPool(new SmallPoolableObjectFactory());

        for (int i = 0 ; i < 1000 ; i++) {
            pool.addObject();
        }

        Object obj = pool.borrowObject();
        assertEquals("1000", obj);
        pool.returnObject(obj);
        obj = null;
        
        assertEquals(1000, pool.getNumIdle());

        try {
            HashMap map = new HashMap();

            for (int i = 0; i < 1000000; i++) {
                map.put(new Integer(i), new String("Fred Flintstone" + i));
            }
        }
        catch (OutOfMemoryError ex) { }
        
        obj = pool.borrowObject();
        assertEquals("1001", obj);
        pool.returnObject(obj);
        obj = null;
            
        assertEquals(1, pool.getNumIdle());
    }

    public void testOutOfMemoryLarge() throws Exception {
        pool = new SoftReferenceObjectPool(new LargePoolableObjectFactory(1000000));

        Object obj = pool.borrowObject();
        assertTrue(((String)obj).startsWith("1."));
        pool.returnObject(obj);
        obj = null;
        
        assertEquals(1, pool.getNumIdle());

        try {
            HashMap map = new HashMap();

            for (int i = 0; i < 1000000; i++) {
                map.put(new Integer(i), new String("Fred Flintstone" + i));
            }
        }
        catch (OutOfMemoryError ex) { }
        
        obj = pool.borrowObject();
        assertTrue(((String)obj).startsWith("2."));
        pool.returnObject(obj);
        obj = null;
            
        assertEquals(1, pool.getNumIdle());
    }

    public void testOutOfMemoryKeepMap() throws Exception {
        pool = new SoftReferenceObjectPool(new LargePoolableObjectFactory(1000000));

        Object obj = pool.borrowObject();
        assertTrue(((String)obj).startsWith("1."));
        pool.returnObject(obj);
        obj = null;
        
        assertEquals(1, pool.getNumIdle());

        // allocate map outside try/catch block
        HashMap map = new HashMap();
        try {
            for (int i = 0; i < 1000000; i++) {
                map.put(new Integer(i), new String("Fred Flintstone" + i));
            }
        }
        catch (OutOfMemoryError ex) { }

        try {
            obj = pool.borrowObject();
            fail("Expected out of memory");
        }
        catch (OutOfMemoryError ex) { }
    }


    public static class SmallPoolableObjectFactory implements PoolableObjectFactory {
        private int counter = 0;
        
        public Object makeObject() {
            counter++;
            return String.valueOf(counter);
        }
        public boolean validateObject(Object obj) {
            return true;
        }
        public void activateObject(Object obj) { }
        public void passivateObject(Object obj) { }
        public void destroyObject(Object obj) { }
    }

    public static class LargePoolableObjectFactory implements PoolableObjectFactory {
        private String buffer;
        private int counter = 0;
        
        public LargePoolableObjectFactory(int size) {
            char[] data = new char[size];
            Arrays.fill(data, '.');
            buffer = new String(data);
        }
        
        public Object makeObject() {
            counter++;
            return String.valueOf(counter) + buffer;
        }
        public boolean validateObject(Object obj) {
            return true;
        }
        public void activateObject(Object obj) { }
        public void passivateObject(Object obj) { }
        public void destroyObject(Object obj) { }
    }
}