易百教程

很多时候我们想通过其他一些编程语言连接到memcached服务器，比如java和php。

Memcached Java客户端

有三种最常用的memcached java客户端API。

• xmemcached
• spymemcached
• gwhalin memcached客户端

Memcached Java示例

在本示例使用了Greg Whalin memcached客户端，它易于理解和使用。 它提供了线程池的所有基本功能。下面是maven依赖项，将其包含在您的项目中。

<dependency>
    <groupId>com.whalin</groupId>
    <artifactId>Memcached-Java-Client</artifactId>
    <version>3.0.2</version>
</dependency>

为了帮助您快速入门，这里提供了一个示例程序来展示可以使用memcached服务器执行的基本功能的使用。

package com.yiibai.memcached.test;

import java.util.HashMap;
import com.whalin.MemCached.MemCachedClient;
import com.whalin.MemCached.SockIOPool;

public class MemcachedJavaClient {

    /**
     * MemcachedJavaClient program to show the usage of different functions
     * that can be performed on Memcached server with Java Client
     * @param args
     */
    public static void main(String[] args) {
        //initialize the SockIOPool that maintains the Memcached Server Connection Pool
        String[] servers = {"localhost:11111"};
        SockIOPool pool = SockIOPool.getInstance("Test1");
        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();
        //Get the Memcached Client from SockIOPool named Test1
        MemCachedClient mcc = new MemCachedClient("Test1");
        //add some value in cache
        System.out.println("add status:"+mcc.add("1", "Original"));
        //Get value from cache
        System.out.println("Get from Cache:"+mcc.get("1"));

        System.out.println("add status:"+mcc.add("1", "Modified"));
        System.out.println("Get from Cache:"+mcc.get("1"));

        //use set function to add/update value, use replace to update and not add
        System.out.println("set status:"+mcc.set("1","Modified"));
        System.out.println("Get from Cache after set:"+mcc.get("1"));

        //use delete function to delete key from cache
        System.out.println("remove status:"+mcc.delete("1"));
        System.out.println("Get from Cache after delete:"+mcc.get("1"));

        //Use getMulti function to retrieve multiple keys values in one function
        // Its helpful in reducing network calls to 1
        mcc.set("2", "2");
        mcc.set("3", "3");
        mcc.set("4", "4");
        mcc.set("5", "5");
        String [] keys = {"1", "2","3","INVALID","5"};
        HashMap<String,Object> hm = (HashMap<String, Object>) mcc.getMulti(keys);

        for(String key : hm.keySet()){
            System.out.println("KEY:"+key+" VALUE:"+hm.get(key));
        }
    }

}

上面的memcache java客户端程序的输出是：

add status:true
Get from Cache:Original
add status:false
Get from Cache:Original
set status:true
Get from Cache after set:Modified
remove status:true
Get from Cache after delete:null
KEY:3 VALUE:3
KEY:2 VALUE:2
KEY:1 VALUE:null
KEY:INVALID VALUE:null
KEY:5 VALUE:5

如果要连接到多个memcached服务器，则必须创建多个SockIOPool实例，然后在获取MemcacheClient实例时使用连接的名称。