me.smoe.adar.pool.commonpool.CommonPool.java Source code

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Here is the source code for me.smoe.adar.pool.commonpool.CommonPool.java

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/**
 * Copyright (c) 2015, adar.w (adar-w@outlook.com) 
 * 
 * http://www.smoe.me
 * 
 * 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 me.smoe.adar.pool.commonpool;

import java.util.LinkedList;
import java.util.List;
import java.util.NoSuchElementException;
import java.util.concurrent.atomic.AtomicInteger;

import org.apache.commons.pool2.PooledObject;
import org.apache.commons.pool2.PooledObjectFactory;
import org.apache.commons.pool2.impl.DefaultPooledObject;
import org.apache.commons.pool2.impl.GenericObjectPool;
import org.apache.commons.pool2.impl.GenericObjectPoolConfig;

/**
 * Common-pool2
 */
public class CommonPool {

    public static void main(String[] args) throws NoSuchElementException, IllegalStateException, Exception {
        GenericObjectPool<Book> objectPool = new GenericObjectPool<Book>(new BookPoolFactory(),
                buildPoolConfig(5, 10, 2));
        prestartCorePool(objectPool);

        List<Book> books = new LinkedList<Book>();
        for (int i = 0; i < 10; i++) {
            books.add(objectPool.borrowObject());
        }

        for (Book book : books) {
            objectPool.returnObject(book);
        }
    }

    private static GenericObjectPoolConfig buildPoolConfig(int corePoolSize, int maxPoolSize, int keepAliveTime) {
        GenericObjectPoolConfig config = new GenericObjectPoolConfig();
        config.setMaxIdle(corePoolSize);
        config.setMaxTotal(maxPoolSize);
        config.setMaxWaitMillis(keepAliveTime);

        return config;
    }

    private static void prestartCorePool(GenericObjectPool<?> objectPool) throws Exception {
        for (int i = 0; i < objectPool.getMaxIdle(); i++) {
            objectPool.addObject();
        }
    }
}

class BookPoolFactory implements PooledObjectFactory<Book> {

    private static AtomicInteger idGen = new AtomicInteger(0);

    /*
     * borrowObject:
     *       1. makeObject(if pool empty)
     *       2. activateObject
     *       3. borrow
     * 
     * returnObject:
     *       1. passivateObject
     *       2. return
     * 
     *       ex: if not core poolobj, will destroy when expire.
     */

    /*
     * Create New
     */
    @Override
    public PooledObject<Book> makeObject() throws Exception {
        System.out.println("MK obj");
        return new DefaultPooledObject<Book>(new Book(idGen.addAndGet(1), "demo"));
    }

    /*
     * ? 
     */
    @Override
    public boolean validateObject(PooledObject<Book> p) {
        System.out.println("YZ obj");
        return true;
    }

    /*
     * Destroy ?
     */
    @Override
    public void destroyObject(PooledObject<Book> p) throws Exception {
        System.out.println("XH obj");
    }

    /*
     * 
     */
    @Override
    public void activateObject(PooledObject<Book> p) throws Exception {
        System.out.println("JH obj");

    }

    /*
     * ?
     */
    @Override
    public void passivateObject(PooledObject<Book> p) throws Exception {
        System.out.println("DH obj");
    }
}

class Book {

    private int id;

    private String name;

    public Book(int id, String name) {
        this.id = id;
        this.name = name;
    }

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    @Override
    public String toString() {
        return super.toString() + " [id=" + id + ", name=" + name + "]";
    }
}