前言
大家在工作中可能會遇到這樣的需求，即Redis讀寫分離，目的是為了壓力分散化。下面我將為大家介紹借助AWS的ELB實現讀寫分離，以寫主讀從為例。
實現
引用庫文件
<!-- redis客戶端 --> <dependency> <groupId>redis.clients</groupId> <artifactId>jedis</artifactId> <version>2.6.2</version> </dependency>
方式一，借助切面
JedisPoolSelector
此類的目的是為讀和寫分別配置不同的注解，用來區分是主還是從。
package com.silence.spring.redis.readwriteseparation;import java.lang.annotation.ElementType;import java.lang.annotation.Retention;import java.lang.annotation.RetentionPolicy;import java.lang.annotation.Target;/** * Created by keysilence on 16/10/26. */@Retention(RetentionPolicy.RUNTIME)@Target(ElementType.METHOD)public @interface JedisPoolSelector { String value();}JedisPoolAspect
此類的目的是針對主和從的注解，進行動態鏈接池調配，即主的使用主鏈接池，從的使用從連接池。
package com.silence.spring.redis.readwriteseparation;import org.aspectj.lang.JoinPoint;import org.aspectj.lang.annotation.Aspect;import org.aspectj.lang.annotation.Before;import org.aspectj.lang.annotation.Pointcut;import org.aspectj.lang.reflect.MethodSignature;import org.springframework.beans.BeansException;import org.springframework.context.ApplicationContext;import org.springframework.context.ApplicationContextAware;import redis.clients.jedis.JedisPool;import javax.annotation.PostConstruct;import java.lang.reflect.Method;import java.util.Date;/** * Created by keysilence on 16/10/26. */@Aspectpublic class JedisPoolAspect implements ApplicationContextAware { private ApplicationContext ctx; @PostConstruct public void init() { System.out.println("jedis pool aspectj started @" + new Date()); } @Pointcut("execution(* com.silence.spring.redis.readwriteseparation.util.*.*(..))") private void allMethod() { } @Before("allMethod()") public void before(JoinPoint point) { Object target = point.getTarget(); String method = point.getSignature().getName(); Class classz = target.getClass(); Class<?>[] parameterTypes = ((MethodSignature) point.getSignature()) .getMethod().getParameterTypes(); try { Method m = classz.getMethod(method, parameterTypes); if (m != null && m.isAnnotationPresent(JedisPoolSelector.class)) { JedisPoolSelector data = m .getAnnotation(JedisPoolSelector.class); JedisPool jedisPool = (JedisPool) ctx.getBean(data.value()); DynamicJedisPoolHolder.putJedisPool(jedisPool); } } catch (Exception e) { e.printStackTrace(); } } public void setApplicationContext(ApplicationContext applicationContext) throws BeansException { this.ctx = applicationContext; }}DynamicJedisPoolHolder
此類目的是存儲當前使用的JedisPool，即上面類賦值后的結果保存。
package com.silence.spring.redis.readwriteseparation;import redis.clients.jedis.JedisPool;/** * Created by keysilence on 16/10/26. */public class DynamicJedisPoolHolder { public static final ThreadLocal<JedisPool> holder = new ThreadLocal<JedisPool>(); public static void putJedisPool(JedisPool jedisPool) { holder.set(jedisPool); } public static JedisPool getJedisPool() { return holder.get(); }}RedisUtils
此類目的是對Redis具體的調用，里面包含使用主還是從的方式調用。
package com.silence.spring.redis.readwriteseparation.util;import com.silence.spring.redis.readwriteseparation.DynamicJedisPoolHolder;import com.silence.spring.redis.readwriteseparation.JedisPoolSelector;import org.slf4j.Logger;import org.slf4j.LoggerFactory;/** * Created by keysilence on 16/10/26. */public class RedisUtils { private static Logger logger = LoggerFactory.getLogger(RedisUtils.class); @JedisPoolSelector("master") public String setString(final String key, final String value) { String ret = DynamicJedisPoolHolder.getJedisPool().getResource().set(key, value); System.out.println("key:" + key + ",value:" + value + ",ret:" + ret); return ret; } @JedisPoolSelector("slave") public String get(final String key) { String ret = DynamicJedisPoolHolder.getJedisPool().getResource().get(key); System.out.println("key:" + key + ",ret:" + ret); return ret; }}spring-datasource.xml
<?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:aop="http://www.springframework.org/schema/aop" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd"> <bean id="poolConfig" class="redis.clients.jedis.JedisPoolConfig"> <!-- 池中最大鏈接數 --> <property name="maxTotal" value="100"/> <!-- 池中最大空閑鏈接數 --> <property name="maxIdle" value="50"/> <!-- 池中最小空閑鏈接數 --> <property name="minIdle" value="20"/> <!-- 當池中鏈接耗盡，調用者最大阻塞時間，超出此時間將跑出異常。（單位：毫秒；默認為-1，表示永不超時） --> <property name="maxWaitMillis" value="1000"/> <!-- 參考：http://biasedbit.com/redis-jedispool-configuration/ --> <!-- 調用者獲取鏈接時，是否檢測當前鏈接有效性。無效則從鏈接池中移除，并嘗試繼續獲取。（默認為false） --> <property name="testOnBorrow" value="true" /> <!-- 向鏈接池中歸還鏈接時，是否檢測鏈接有效性。（默認為false） --> <property name="testOnReturn" value="true" /> <!-- 調用者獲取鏈接時，是否檢測空閑超時。如果超時，則會被移除（默認為false） --> <property name="testWhileIdle" value="true" /> <!-- 空閑鏈接檢測線程一次運行檢測多少條鏈接 --> <property name="numTestsPerEvictionRun" value="10" /> <!-- 空閑鏈接檢測線程檢測周期。如果為負值，表示不運行檢測線程。（單位：毫秒，默認為-1） --> <property name="timeBetweenEvictionRunsMillis" value="60000" /> <!-- 鏈接獲取方式。隊列：false；棧：true --> <!--<property name="lifo" value="false" />--> </bean> <bean id="master" class="redis.clients.jedis.JedisPool"> <constructor-arg index="0" ref="poolConfig"/> <constructor-arg index="1" value="192.168.100.110" type="java.lang.String"/> <constructor-arg index="2" value="6379" type="int"/> </bean> <bean id="slave" class="redis.clients.jedis.JedisPool"> <constructor-arg index="0" ref="poolConfig"/> <!-- 此處Host配置成ELB地址 --> <constructor-arg index="1" value="192.168.100.110" type="java.lang.String"/> <constructor-arg index="2" value="6380" type="int"/> </bean> <bean id="redisUtils" class="com.silence.spring.redis.readwriteseparation.util.RedisUtils"> </bean> <bean id="jedisPoolAspect" class="com.silence.spring.redis.readwriteseparation.JedisPoolAspect" /> <aop:aspectj-autoproxy proxy-target-class="true"/></beans>
Test
package com.silence.spring.redis.readwriteseparation;import com.silence.spring.redis.readwriteseparation.util.RedisUtils;import org.springframework.context.ApplicationContext;import org.springframework.context.support.ClassPathXmlApplicationContext;/** * Created by keysilence on 16/10/26. */public class Test { public static void main(String[] args) { ApplicationContext ctx = new ClassPathXmlApplicationContext("spring-datasource.xml"); System.out.println(ctx); RedisUtils redisUtils = (RedisUtils) ctx.getBean("redisUtils"); redisUtils.setString("aaa", "111"); System.out.println(redisUtils.get("aaa")); }}方式二，依賴注入
與方式一類似，但是需要寫死具體使用主的池還是從的池，思路如下：
放棄注解的方式，直接將主和從的兩個鏈接池注入到具體實現類中。
RedisUtils
package com.silence.spring.redis.readwriteseparation.util;import com.silence.spring.redis.readwriteseparation.DynamicJedisPoolHolder;import com.silence.spring.redis.readwriteseparation.JedisPoolSelector;import org.slf4j.Logger;import org.slf4j.LoggerFactory;import redis.clients.jedis.JedisPool;/** * Created by keysilence on 16/10/26. */public class RedisUtils { private static Logger logger = LoggerFactory.getLogger(RedisUtils.class); private JedisPool masterJedisPool; private JedisPool slaveJedisPool; public void setMasterJedisPool(JedisPool masterJedisPool) { this.masterJedisPool = masterJedisPool; } public void setSlaveJedisPool(JedisPool slaveJedisPool) { this.slaveJedisPool = slaveJedisPool; } public String setString(final String key, final String value) { String ret = masterJedisPool.getResource().set(key, value); System.out.println("key:" + key + ",value:" + value + ",ret:" + ret); return ret; } public String get(final String key) { String ret = slaveJedisPool.getResource().get(key); System.out.println("key:" + key + ",ret:" + ret); return ret; }}spring-datasource.xml
<?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:aop="http://www.springframework.org/schema/aop" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd"> <bean id="poolConfig" class="redis.clients.jedis.JedisPoolConfig"> <!-- 池中最大鏈接數 --> <property name="maxTotal" value="100"/> <!-- 池中最大空閑鏈接數 --> <property name="maxIdle" value="50"/> <!-- 池中最小空閑鏈接數 --> <property name="minIdle" value="20"/> <!-- 當池中鏈接耗盡，調用者最大阻塞時間，超出此時間將跑出異常。（單位：毫秒；默認為-1，表示永不超時） --> <property name="maxWaitMillis" value="1000"/> <!-- 參考：http://biasedbit.com/redis-jedispool-configuration/ --> <!-- 調用者獲取鏈接時，是否檢測當前鏈接有效性。無效則從鏈接池中移除，并嘗試繼續獲取。（默認為false） --> <property name="testOnBorrow" value="true" /> <!-- 向鏈接池中歸還鏈接時，是否檢測鏈接有效性。（默認為false） --> <property name="testOnReturn" value="true" /> <!-- 調用者獲取鏈接時，是否檢測空閑超時。如果超時，則會被移除（默認為false） --> <property name="testWhileIdle" value="true" /> <!-- 空閑鏈接檢測線程一次運行檢測多少條鏈接 --> <property name="numTestsPerEvictionRun" value="10" /> <!-- 空閑鏈接檢測線程檢測周期。如果為負值，表示不運行檢測線程。（單位：毫秒，默認為-1） --> <property name="timeBetweenEvictionRunsMillis" value="60000" /> <!-- 鏈接獲取方式。隊列：false；棧：true --> <!--<property name="lifo" value="false" />--> </bean> <bean id="masterJedisPool" class="redis.clients.jedis.JedisPool"> <constructor-arg index="0" ref="poolConfig"/> <constructor-arg index="1" value="192.168.100.110" type="java.lang.String"/> <constructor-arg index="2" value="6379" type="int"/> </bean> <bean id="slaveJedisPool" class="redis.clients.jedis.JedisPool"> <constructor-arg index="0" ref="poolConfig"/> <constructor-arg index="1" value="192.168.100.110" type="java.lang.String"/> <constructor-arg index="2" value="6380" type="int"/> </bean> <bean id="redisUtils" class="com.silence.spring.redis.readwriteseparation.util.RedisUtils"> <property name="masterJedisPool" ref="masterJedisPool"/> <property name="slaveJedisPool" ref="slaveJedisPool"/> </bean></beans>
以上就是本文的全部內容，希望對大家的學習有所幫助，也希望大家多多支持VEVB武林網。
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