昊天

1.memcached client for java
http://www.whalin.com/memcached

import com.danga.MemCached.*;
import org.apache.log4j.*;
public class TestMemcached {
    public static void main(String[] args) {
        /*初始化SockIOPool，管理memcached的连接池*/
        String[] servers = { "192.168.1.20:12111" };
        SockIOPool pool = SockIOPool.getInstance();
        pool.setServers(servers);
        pool.setFailover(true);
        pool.setInitConn(10);
        pool.setMinConn(5);
        pool.setMaxConn(250);
        pool.setMaintSleep(30);
        pool.setNagle(false);
        pool.setSocketTO(3000);
        pool.setAliveCheck(true);
        pool.initialize();
        /*建立MemcachedClient实例*/
        MemCachedClient memCachedClient = new MemCachedClient();
        for (int i = 0; i < 10; i++) {
            /*将对象加入到memcached缓存*/
            boolean success = memCachedClient.set("" + i, "Hello!");
            /*从memcached缓存中按key值取对象*/
            String result = (String) memCachedClient.get("" + i);
            System.out.println(String.format("set( %d ): %s", i, success));
            System.out.println(String.format("get( %d ): %s", i, result));
        }
    }
}

2.spymemcached
http://code.google.com/p/spymemcached/

用spymemcached将对象存入缓存

import java.net.InetSocketAddress;
import java.util.concurrent.Future;

import net.spy.memcached.MemcachedClient;

public class MClient {

    public static void main(String[] args){
        try{
            /*建立MemcachedClient 实例，并指定memcached服务的IP地址和端口号*/
            MemcachedClient mc = new MemcachedClient(new InetSocketAddress("192.168.1.20", 12111));
            Future<Boolean> b = null;
            /*将key值，过期时间(秒)和要缓存的对象set到memcached中*/
            b = mc.set("neea:testDaF:ksIdno", 900, "someObject");
            if(b.get().booleanValue()==true){
                mc.shutdown();
            }
        }
        catch(Exception ex){
            ex.printStackTrace();
        }
    }
}

用spymemcached从缓存中取得对象

import java.net.InetSocketAddress;
import java.util.concurrent.Future;

import net.spy.memcached.MemcachedClient;

public class MClient {

    public static void main(String[] args){
        try{
            /*建立MemcachedClient 实例，并指定memcached服务的IP地址和端口号*/
            MemcachedClient mc = new MemcachedClient(new InetSocketAddress("192.168.1.20", 12111));
            /*按照key值从memcached中查找缓存，不存在则返回null */
Object b = mc.get("neea:testDaF:ksIdno ");
            mc.shutdown();
        }
        catch(Exception ex){
            ex.printStackTrace();
        }
    }
}

以上两种API比较
memcached client for java：较早推出的memcached JAVA客户端API，应用广泛，运行比较稳定。
spymemcached：A simple， asynchronous， single-threaded memcached client written in java. 支持异步，单线程的memcached客户端，用到了java1.5版本的concurrent和nio，存取速度会高于前者，但是稳定性不好，测试中常报timeOut等相关异常。
由于memcached client for java发布了新版本，性能上有所提高，并且运行稳定，所以建议使用memcached client for java.

3. Xmemcached
http://code.google.com/p/xmemcached/