Memcached筆記——（二）XMemcached&Spring整合

今天研究Memcached的Java的Client，使用XMemcached 1.3.5，做個簡單的測試，並介紹如何與Spring整合。

相關連結：
Memcached筆記——（一）安裝&常規錯誤&監控
Memcached筆記——（二）XMemcached&Spring整合
Memcached筆記——（三）Memcached使用總結
Memcached筆記——（四）應對高併發攻擊


一、Memcached Client簡要介紹
Memcached Client目前有3種：

• Memcached Client for Java
• SpyMemcached
• XMemcached

這三種Client一直存在各種爭議：

• Memcached Client for Java 比 SpyMemcached更穩定、更早、更廣泛；
• SpyMemcached 比 Memcached Client for Java更高效；
• XMemcached 比 SpyMemcache併發效果更好。

用資料來說話，參考官方效能對比：
Memcached Client for Java：https://github.com/gwhalin/Memcached-Java-Client/wiki/PERFORMANCE
XMemcached：http://xmemcached.googlecode.com/svn/trunk/benchmark/benchmark.html

二、XMemcached特性
XMemcached特性：

• 高效能
• 支援完整的memcached文字協議,二進位制協議。
• 支援JMX，可以通過MBean調整效能引數、動態新增/移除server、檢視統計等。
• 支援客戶端統計
• 支援memcached節點的動態增減。
• 支援memcached分佈:餘數分佈和一致性雜湊分佈。
• 更多的效能調整選項。

此外，XMemcached更容易與Spring整合。而且，屬於中國原創！

三、XMemcached簡單實現

MemcachedClientBuilder是MemcachedClient核心介面，用來控制Client的構建（build()方法）和關閉（shutdown()方法）。
XMemcachedClientBuilder一般通過構造方法配置地址列表，通常還要配置權重，程式碼如下：

	public XMemcachedClientBuilder(List<InetSocketAddress> addressList) {
		if (addressList != null) {
			for (InetSocketAddress addr : addressList) {
				this.addressMap.put(addr, null);
			}
		}
	}

	public XMemcachedClientBuilder(List<InetSocketAddress> addressList,
			int[] weights) {
		if (addressList != null) {
			for (InetSocketAddress addr : addressList) {
				this.addressMap.put(addr, null);
			}
		}
		this.weights = weights;
	}

不過這哥們如果用this()可以省點程式碼， 還有給加點註釋吧！
此外，還需要設定連線池大小，使用二進位制協議/文字協議等。
通過build()方法獲得MemcachedClient
然後就可以通過Memcached進行set、get、replace、delete等Memcached操作了！
上程式碼：

import static junit.framework.Assert.*;

import java.io.IOException;
import java.util.concurrent.TimeoutException;

import net.rubyeye.xmemcached.MemcachedClient;
import net.rubyeye.xmemcached.MemcachedClientBuilder;
import net.rubyeye.xmemcached.XMemcachedClientBuilder;
import net.rubyeye.xmemcached.command.BinaryCommandFactory;
import net.rubyeye.xmemcached.exception.MemcachedException;
import net.rubyeye.xmemcached.utils.AddrUtil;

import org.junit.Test;

public class MemcachedClientTest {
	@Test
	public void test() {
		MemcachedClientBuilder builder = new XMemcachedClientBuilder(
				AddrUtil.getAddresses("10.11.155.26:11211 10.11.155.41:11211 10.10.76.31:11211 10.10.76.35:11211"),
				new int[] { 1, 1, 1, 1 });
		
		// 設定連線池大小，即客戶端個數
		builder.setConnectionPoolSize(50);

		// 當機報警
		builder.setFailureMode(true);

		// 使用二進位制檔案
		builder.setCommandFactory(new BinaryCommandFactory());

		MemcachedClient memcachedClient = null;
		try {
			memcachedClient = builder.build();
			try {
				// 設定/獲取
				memcachedClient.set("zlex", 36000, "set/get");
				assertEquals("set/get", memcachedClient.get("zlex"));

				// 替換
				memcachedClient.replace("zlex", 36000, "replace");
				assertEquals("replace", memcachedClient.get("zlex"));

				// 移除
				memcachedClient.delete("zlex");
				assertNull(memcachedClient.get("zlex"));
			} catch (TimeoutException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			} catch (InterruptedException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			} catch (MemcachedException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}

		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} finally {
			if (memcachedClient != null) {
				try {
					memcachedClient.shutdown();
				} catch (IOException e) {
					// TODO Auto-generated catch block
					e.printStackTrace();
				}
			}
		}
	}
}

四、XMemcached與Spring整合
XMemcached與Spring整合可以參考http://code.google.com/p/xmemcached/wiki/Spring_Integration，這裡只說最常用的方法。
memcached.properties做基本配置：

#連線池大小即客戶端個數
memcached.connectionPoolSize=50
memcached.failureMode=true
#server1
memcached.server1.host=10.11.155.26
memcached.server1.port=11211
memcached.server1.weight=4
#server2
memcached.server2.host=10.11.155.41
memcached.server2.port=11211
memcached.server2.weight=3				
#server3
memcached.server3.host=10.10.76.31
memcached.server3.port=11211
memcached.server3.weight=2					
#server4
memcached.server4.host=10.10.76.35
memcached.server4.port=11211
memcached.server4.weight=1		 
	 

XML配置檔案：

<?xml version="1.0" encoding="UTF-8"?>
<beans
	xmlns="http://www.springframework.org/schema/beans"
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xmlns:context="http://www.springframework.org/schema/context"
	xmlns:p="http://www.springframework.org/schema/p"
	xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
		http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd">
	<!-- http://code.google.com/p/xmemcached/wiki/Spring_Integration -->
	<context:property-placeholder location="memcached.properties" />
	<bean
		id="memcachedClientBuilder"
		class="net.rubyeye.xmemcached.XMemcachedClientBuilder"
		p:connectionPoolSize="${memcached.connectionPoolSize}"
		p:failureMode="${memcached.failureMode}">
		<!-- XMemcachedClientBuilder have two arguments.First is server list,and 
			second is weights array. -->
		<constructor-arg>
			<list>
				<bean class="java.net.InetSocketAddress">
					<constructor-arg>
						<value>${memcached.server1.host}</value>
					</constructor-arg>
					<constructor-arg>
						<value>${memcached.server1.port}</value>
					</constructor-arg>
				</bean>
				<bean class="java.net.InetSocketAddress">
					<constructor-arg>
						<value>${memcached.server2.host}</value>
					</constructor-arg>
					<constructor-arg>
						<value>${memcached.server2.port}</value>
					</constructor-arg>
				</bean>
				<bean class="java.net.InetSocketAddress">
					<constructor-arg>
						<value>${memcached.server3.host}</value>
					</constructor-arg>
					<constructor-arg>
						<value>${memcached.server3.port}</value>
					</constructor-arg>
				</bean>
				<bean class="java.net.InetSocketAddress">
					<constructor-arg>
						<value>${memcached.server4.host}</value>
					</constructor-arg>
					<constructor-arg>
						<value>${memcached.server4.port}</value>
					</constructor-arg>
				</bean>
			</list>
		</constructor-arg>
		<constructor-arg>
			<list>
				<value>${memcached.server1.weight}</value>
				<value>${memcached.server2.weight}</value>
				<value>${memcached.server3.weight}</value>
				<value>${memcached.server4.weight}</value>
			</list>
		</constructor-arg>
		<property name="commandFactory">
			<bean class="net.rubyeye.xmemcached.command.TextCommandFactory" />
		</property>
		<property name="sessionLocator">
			<bean class="net.rubyeye.xmemcached.impl.KetamaMemcachedSessionLocator" />
		</property>
		<property name="transcoder">
			<bean class="net.rubyeye.xmemcached.transcoders.SerializingTranscoder" />
		</property>
	</bean>
	<!-- Use factory bean to build memcached client -->
	<bean
		id="memcachedClient"
		factory-bean="memcachedClientBuilder"
		factory-method="build"
		destroy-method="shutdown" />
</beans>

這裡的memcachedClientBuilder節點完成MemcachedClientBuilder，然後通過memcachedClient節點配置factory-method，呼叫MemcachedClientBuilder的build()方法產生MemcachedClient，並配置destroy-method進行關閉。
不過我還是疑惑，這裡的異常由誰來處理？Spring容器嗎？ 或者需要另一個代理Bean包裝一下？

有了Spring容器支援，我們不需要在程式碼中進行配置，也不需要重複呼叫build()跟shutdown()方法，這些操作交給Spring來完成。
程式碼如下：

import static junit.framework.Assert.*;

import java.util.concurrent.TimeoutException;

import net.rubyeye.xmemcached.MemcachedClient;
import net.rubyeye.xmemcached.exception.MemcachedException;

import org.junit.Before;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

public class MemcachedSpringTest {

	private ApplicationContext app;
	private MemcachedClient memcachedClient;

	@Before
	public void init() {
		app = new ClassPathXmlApplicationContext("applicationContext.xml");
		memcachedClient = (MemcachedClient) app.getBean("memcachedClient");
	}

	@Test
	public void test() {
		try {
			// 設定/獲取
			memcachedClient.set("zlex", 36000, "set/get");
			assertEquals("set/get", memcachedClient.get("zlex"));

			// 替換
			memcachedClient.replace("zlex", 36000, "replace");
			assertEquals("replace", memcachedClient.get("zlex"));

			// 移除
			memcachedClient.delete("zlex");
			assertNull(memcachedClient.get("zlex"));
		} catch (TimeoutException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (InterruptedException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (MemcachedException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}
}

相關連結：
Memcached筆記——（一）安裝&常規錯誤&監控
Memcached筆記——（二）XMemcached&Spring整合
Memcached筆記——（三）Memcached使用總結
Memcached筆記——（四）應對高併發攻擊