Commons.pool2 之簡單實例

package com.play.english.commonpool;

/**
 * @author chaiqx on 2019/12/13
 */
public class CqxConnection {

    private int id;

    public CqxConnection(int id) {
        this.id = id;
    }

    public int getId() {
        return id;
    }

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

package com.play.english.commonpool;

import org.apache.commons.pool2.BasePooledObjectFactory;
import org.apache.commons.pool2.PooledObject;
import org.apache.commons.pool2.impl.DefaultPooledObject;

import java.util.concurrent.atomic.AtomicInteger;

/**
 * @author chaiqx on 2019/12/13
 */
public class CqxConnectionFactory extends BasePooledObjectFactory<CqxConnection> {

    private AtomicInteger counter = new AtomicInteger(0);

    @Override
    public CqxConnection create() throws Exception {
        return new CqxConnection(counter.incrementAndGet());
    }

    @Override
    public PooledObject<CqxConnection> wrap(CqxConnection cqxConnection) {
        return new DefaultPooledObject<>(cqxConnection);
    }
}

package com.play.english.commonpool;

import org.apache.commons.pool2.PooledObjectFactory;
import org.apache.commons.pool2.impl.AbandonedConfig;
import org.apache.commons.pool2.impl.GenericObjectPool;
import org.apache.commons.pool2.impl.GenericObjectPoolConfig;

/**
 * @author chaiqx on 2019/12/13
 */
public class CqxConnectionPool extends GenericObjectPool<CqxConnection> {

    public CqxConnectionPool(PooledObjectFactory<CqxConnection> factory) {
        super(factory);
    }

    public CqxConnectionPool(PooledObjectFactory<CqxConnection> factory, GenericObjectPoolConfig config) {
        super(factory, config);
    }

    public CqxConnectionPool(PooledObjectFactory<CqxConnection> factory, GenericObjectPoolConfig config, AbandonedConfig abandonedConfig) {
        super(factory, config, abandonedConfig);
    }
}

package com.play.english.commonpool;

import org.apache.commons.pool2.impl.AbandonedConfig;
import org.apache.commons.pool2.impl.GenericObjectPoolConfig;

/**
 * @author chaiqx on 2019/12/13
 */
public class TestCqxConnectionPool {

    private CqxConnectionFactory cqxConnectionFactory;
    private GenericObjectPoolConfig objectPoolConfig;
    private CqxConnectionPool cqxConnectionPool;

    private void testCqxConnectionPool() {
        cqxConnectionFactory = new CqxConnectionFactory();
        objectPoolConfig = new GenericObjectPoolConfig();
        objectPoolConfig.setMaxTotal(5);//最大的連接數
        objectPoolConfig.setMaxIdle(5);//最大空閒連接數
        objectPoolConfig.setMaxWaitMillis(1000);//最長等待時間
        AbandonedConfig abandonedConfig = new AbandonedConfig();
        abandonedConfig.setRemoveAbandonedOnMaintenance(true); //在Maintenance的時候檢查是否有泄漏
        abandonedConfig.setRemoveAbandonedOnBorrow(true); //borrow 的時候檢查泄漏
        abandonedConfig.setRemoveAbandonedTimeout(30); //如果一個對象borrow之後30秒還沒有返還給pool，認爲是泄漏的對象
        cqxConnectionPool = new CqxConnectionPool(cqxConnectionFactory, objectPoolConfig, abandonedConfig);

        //多線程情況
        for (int i = 0; i < 7; i++) {
            new Thread() {
                @Override
                public void run() {
                    CqxConnectionExecutor cqxConnectionExecutor = new CqxConnectionExecutor() {
                        @Override
                        protected Object innerCall(CqxConnection cqxConnection) {
                            return cqxConnection.getId();
                        }
                    };
                    System.out.println(cqxConnectionExecutor.exec(-1));
                }
            }.start();
        }

        //單線程順序情況
        for (int i = 0; i < 7; i++) {
            CqxConnectionExecutor cqxConnectionExecutor = new CqxConnectionExecutor() {
                @Override
                protected Object innerCall(CqxConnection cqxConnection) {
                    return cqxConnection.getId();
                }
            };
            System.out.println(cqxConnectionExecutor.exec(-1));
        }
    }

    public static void main(String[] args) {
        new TestCqxConnectionPool().testCqxConnectionPool();
    }

    protected abstract class CqxConnectionExecutor<T> {

        abstract protected T innerCall(CqxConnection cqxConnection);

        public T exec(T fail) {
            try {
                CqxConnection cqxConnection = cqxConnectionPool.borrowObject();
                System.out.println("created cnt = " + cqxConnectionPool.getCreatedCount());
                System.out.println("borrowed cnt = " + cqxConnectionPool.getBorrowedCount());
                System.out.println("destroy cnt = " + cqxConnectionPool.getDestroyedCount());
                System.out.println("idle cnt = " + cqxConnectionPool.getNumIdle());
                System.out.println("active cnt = " + cqxConnectionPool.getNumActive());
                System.out.println("waiter cnt = " + cqxConnectionPool.getNumWaiters());
                System.out.println("returned cnt = " + cqxConnectionPool.getReturnedCount());
                T t = innerCall(cqxConnection);
                cqxConnectionPool.returnObject(cqxConnection);
                return t;
            } catch (Exception e) {
                return fail;
            }
        }
    }
}