SSM 集成redis实现缓存

╰半橙微兮° 2024-02-18 18:39 32阅读 0赞

### 操作步骤: ###

1.使用maven导入包

<dependency>
    			<groupId>org.springframework.data</groupId>
    			<artifactId>spring-data-redis</artifactId>
    			<version>1.8.4.RELEASE</version>
    		</dependency>
    
    
    		
    		
    		<dependency>
    			<groupId>redis.clients</groupId>
    			<artifactId>jedis</artifactId>
    			<version>2.9.0</version>
    		</dependency>
    
    		
    		
    		<dependency>
    			<groupId>org.mybatis.caches</groupId>
    			<artifactId>mybatis-ehcache</artifactId>
    			<version>1.1.0</version>
    		</dependency>

2.RedisCache类

package com.hlx.util;
    
    import java.util.concurrent.locks.ReadWriteLock;
    import java.util.concurrent.locks.ReentrantReadWriteLock;
    
    import org.apache.ibatis.cache.Cache;
    import org.slf4j.Logger;
    import org.slf4j.LoggerFactory;
    import org.springframework.data.redis.connection.RedisConnection;
    import org.springframework.data.redis.connection.jedis.JedisConnectionFactory;
    import org.springframework.data.redis.serializer.JdkSerializationRedisSerializer;
    import org.springframework.data.redis.serializer.RedisSerializer;
    
    import redis.clients.jedis.exceptions.JedisConnectionException;
    
    /**
     * 
     * 使用第三方内存数据库Redis作为二级缓存
     * 
     * 这个类实现了mybatis中的缓存机制
     * 
     */
    public class RedisCache implements Cache {
    
    	// 日志跟踪对象
    	private static final Logger logger = LoggerFactory
    			.getLogger(RedisCache.class);
    
    	// 连接工厂对象
    	private static JedisConnectionFactory jedisConnectionFactory;
    
    	private final String id;
    
    	/**
    	 * The {@code ReadWriteLock}.
    	 * ReadWriteLock管理一组锁，一个是只读的锁，一个是写锁。读锁可以在没有写锁的时候被多个线程同时持有，写锁是独占的。
    	 * 
    	 * http://blog.csdn.net/qq_19431333/article/details/70568478
    	 */
    	private final ReadWriteLock readWriteLock = new ReentrantReadWriteLock();
    
    	/**
    	 * 获得缓存的ID
    	 * 
    	 * @param id
    	 */
    	public RedisCache(final String id) {
    		if (id == null) {
    			throw new IllegalArgumentException("Cache instances require an ID");
    		}
    		logger.debug("MybatisRedisCache:id=" + id);
    		this.id = id;
    	}
    
    	/**
    	 * 清空缓存
    	 */
    	@Override
    	public void clear() {
    		RedisConnection connection = null;
    		try {
    			connection = jedisConnectionFactory.getConnection();
    			connection.flushDb();
    			connection.flushAll();
    		} catch (JedisConnectionException e) {
    			e.printStackTrace();
    		} finally {
    			if (connection != null) {
    				connection.close();
    			}
    		}
    	}
    
    	@Override
    	public String getId() {
    		return this.id;
    	}
    
    	/**
    	 * 通过key获得数据value
    	 */
    	@Override
    	public Object getObject(Object key) {
    		Object result = null;
    		RedisConnection connection = null;
    		try {
    			connection = jedisConnectionFactory.getConnection();
    			RedisSerializer<Object> serializer = new JdkSerializationRedisSerializer();
    			result = serializer.deserialize(connection.get(serializer
    					.serialize(key)));
    		} catch (JedisConnectionException e) {
    			e.printStackTrace();
    		} finally {
    			if (connection != null) {
    				connection.close();
    			}
    		}
    		return result;
    	}
    
    	@Override
    	public ReadWriteLock getReadWriteLock() {
    		// TODO Auto-generated method stub
    		return this.readWriteLock;
    	}
    
    	/**
    	 * 数据大小
    	 */
    	@Override
    	public int getSize() {
    		int result = 0;
    		RedisConnection connection = null;
    		try {
    			connection = jedisConnectionFactory.getConnection();
    			result = Integer.valueOf(connection.dbSize().toString());
    		} catch (JedisConnectionException e) {
    			e.printStackTrace();
    		} finally {
    			if (connection != null) {
    				connection.close();
    			}
    		}
    		return result;
    	}
    
    	/**
    	 * 存入数据key-value
    	 */
    	@Override
    	public void putObject(Object key, Object value) {
    		RedisConnection connection = null;
    		try {
    			connection = jedisConnectionFactory.getConnection();
    			RedisSerializer<Object> serializer = new JdkSerializationRedisSerializer();
    			connection.set(serializer.serialize(key),
    					serializer.serialize(value));
    		} catch (JedisConnectionException e) {
    			e.printStackTrace();
    		} finally {
    			if (connection != null) {
    				connection.close();
    			}
    		}
    	}
    
    	/**
    	 * 根据key删除数据
    	 */
    	@Override
    	public Object removeObject(Object key) {
    		RedisConnection connection = null;
    		Object result = null;
    		try {
    			connection = jedisConnectionFactory.getConnection();
    			RedisSerializer<Object> serializer = new JdkSerializationRedisSerializer();
    			result = connection.expire(serializer.serialize(key), 0);
    		} catch (JedisConnectionException e) {
    			e.printStackTrace();
    		} finally {
    			if (connection != null) {
    				connection.close();
    			}
    		}
    		return result;
    	}
    
    	/**
    	 * 设置jedis连接工厂对象
    	 * 
    	 * @param jedisConnectionFactory
    	 */
    	public static void setJedisConnectionFactory(
    			JedisConnectionFactory jedisConnectionFactory) {
    		RedisCache.jedisConnectionFactory = jedisConnectionFactory;
    	}
    
    }

3.RedisCacheTransfer类

package com.hlx.util;
    
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.data.redis.connection.jedis.JedisConnectionFactory;
    /**
     *  静态注入中间类
     * @author Administrator
     *
     */
    public class RedisCacheTransfer {
    	@Autowired
    	public void setJedisConnectionFactory(
    			JedisConnectionFactory jedisConnectionFactory) {
    		RedisCache.setJedisConnectionFactory(jedisConnectionFactory);
    
    	}
    }

4.配置文件redis.properties

redis.host=192.168.0.101
    redis.port=6379
    redis.pass=
    redis.maxIdle=600
    redis.maxTotal=1024
    redis.maxWait=10000
    redis.testOnBorrow=true

5.配置文件applicationContext-redis.xml

<bean id="poolConfig" class="redis.clients.jedis.JedisPoolConfig">
    		<property name="maxIdle" value="${redis.maxIdle}" />
    		<property name="maxTotal" value="${redis.maxTotal}" />
    		<property name="maxWaitMillis" value="${redis.maxWait}" />
    		<property name="testOnBorrow" value="${redis.testOnBorrow}" />
    	</bean>
    
    	
    	<bean id="jedisConnectionFactory"
    		class="org.springframework.data.redis.connection.jedis.JedisConnectionFactory">
    		<property name="hostName" value="${redis.host}" />
    		<property name="port" value="${redis.port}" />
    		<property name="password" value="${redis.pass}" />
    		<property name="poolConfig" ref="poolConfig" />
    	</bean>
    
    	
    	<bean id="redisCacheTransfer" class="com.hlx.util.RedisCacheTransfer">
    		<property name="jedisConnectionFactory" ref="jedisConnectionFactory" />
    	</bean>

6.配置文件mybatis-config.xml

<?xml version="1.0" encoding="UTF-8" ?>
    <!DOCTYPE configuration
    PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
    "http://mybatis.org/dtd/mybatis-3-config.dtd">
    <configuration>
    
    	
    
    	
    
    	
    	<settings>
    
             
            <setting name="logImpl" value="LOG4J"/>
            
    		
    		<setting name="cacheEnabled" value="true" />
    
    		
    		<setting name="lazyLoadingEnabled" value="false" />
    
    		
    		<setting name="multipleResultSetsEnabled" value="true" />
    
    		
    		<setting name="aggressiveLazyLoading" value="true" />
    
    	</settings>
    	
    </configuration>

7.配置文件applicationContext-dao.xml

<bean id="sessionFactoryBean" class="org.mybatis.spring.SqlSessionFactoryBean">
    		
    		<property name="dataSource" ref="druidDataSource" />
    		
    		<property name="mapperLocations" value="classpath:com/hlx/mapper/*Mapper.xml" />
    		
    		<property name="typeAliasesPackage" value="com.hlx.entity" />
    		
    		<property name="configLocation" value="classpath:mybatis-config.xml" />
    	</bean>

8.在查询的实体类中配置BookMapper.xml

<?xml version="1.0" encoding="UTF-8" ?>
    <!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd" >
    <mapper namespace="com.hlx.dao.BookMapper" >
    
    <cache eviction="LRU" type="com.hlx.util.RedisCache"/>

9.在Controller类中

@RequestMapping("/find2")
    	public String find(ModelMap model) {
    
    		// 调用业务方法
    		Book books = service.find(2);
    
    		 System.out.println(books);
    		// 保存
    		model.put("book", books);
    
    		return "my";
    
    	}

10.实体类实现 implements Serializable

11.在JSP页面显示数据

<h1>${book.bid }   ${book.bname }  </h1>

12.运行http://localhost:8080/mavenssm3/find2.action

![Center][]

13.如何查看是否用了缓存?

a)使用log4j.properties

log4j.rootLogger=DEBUG,CONSOLE,FILEOUT   
    log4j.addivity.org.apache=true  
      
      
    # CONSOLE  \u6253\u5370\u5230\u63A7\u5236\u53F0  
    log4j.appender.CONSOLE=org.apache.log4j.ConsoleAppender  
    log4j.appender.Threshold=DEBUG  
    log4j.appender.CONSOLE.Target=System.out  
    log4j.appender.CONSOLE.layout=org.apache.log4j.PatternLayout  
    log4j.appender.CONSOLE.layout.ConversionPattern=[%-5p] %d{yyyy-MM-dd HH\:mm\:ss} \:%m%n  
      
      
    #  
    # FILEOUT \u6253\u5370\u5230 <span style="font-family: Arial, Helvetica, sans-serif;">D\:\\report.log</span>  
    log4j.appender.FILEOUT=org.apache.log4j.RollingFileAppender  
    log4j.appender.FILEOUT.File=D\:\\report.log  
    log4j.appender.FILEOUT.layout=org.apache.log4j.PatternLayout  
    log4j.appender.fileout.MaxFileSize=100000KB  
      
      
    log4j.appender.FILEOUT.Append=true  
    #log4j.appender.CONSOLE.layout.ConversionPattern=[framework] %d \u2013 %c -%-4r [%t] %-5p %c %x \u2013 %m%n  
    log4j.appender.FILEOUT.layout.ConversionPattern=[%-5p]_%d{yyyy-MM-dd HH\:mm\:ss} \:%m%n

b)导入相关的包

第一次查询

![Center 1][]

再次查询

![Center 2][]

再次查询

![Center 2][]

注意:后面查询相同就不会再产生SQL语句,就会到Redis缓存去查找!!

[Center]: https://image.dandelioncloud.cn/pgy_files/images/2024/01/29/68590d6b4a6d464794daf7816d83fda3.png
[Center 1]: https://image.dandelioncloud.cn/pgy_files/images/2024/01/29/c3585e020e8648c7a2a19ab73652059d.png
[Center 2]: https://image.dandelioncloud.cn/pgy_files/images/2024/01/29/ac211c38a226451f8262ce105c283c38.png