[java][49]Redis入门2--java实现Redis连接池Demo

  教程：spring整合redis简单demo

  本文完全参考上面教程，但实现过程中出现了若干问题，故对代码做了若干修改，纯属笔记。

1. 建Maven工程

2. 工程结构

3. 代码

1）pom.xml

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>

  <groupId>com.example</groupId>
  <artifactId>redis</artifactId>
  <version>0.0.1-SNAPSHOT</version>
  <packaging>jar</packaging>

  <name>redis</name>
  <url>http://maven.apache.org</url>

  <properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
  </properties>

  <dependencies>
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>4.12</version>
      <scope>test</scope>
    </dependency>
    
  <dependency>  
    <groupId>org.slf4j</groupId>  
    <artifactId>slf4j-simple</artifactId>  
    <version>1.7.25</version>  
  </dependency>  
    
  <dependency>
    <groupId>javax.servlet</groupId>
    <artifactId>javax.servlet-api</artifactId>
    <version>3.1.0</version>
    <scope>provided</scope>
  </dependency>
    
    <dependency>
        <groupId>org.springframework.data</groupId>
        <artifactId>spring-data-redis</artifactId>
        <version>1.7.1.RELEASE</version>
    </dependency>
    <dependency>
	    <groupId>redis.clients</groupId>
	    <artifactId>jedis</artifactId>
	    <version>2.8.0</version>
	</dependency>
  </dependencies>
</project>

2）applicationContext.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:p="http://www.springframework.org/schema/p"
    xmlns:context="http://www.springframework.org/schema/context"
    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
    ">

    <context:component-scan base-package="com.example.redis.dao" />
    <context:property-placeholder location="classpath:applicationContext.properties" />

    <!-- 连接池配置 -->
    <bean id="jpoolConfig" class="redis.clients.jedis.JedisPoolConfig"
        p:maxIdle="${redis.maxIdle}" p:maxWaitMillis="${redis.maxWait}"
        p:testOnBorrow="${redis.testOnBorrow}" />

    <!--链接配置 -->
    <bean id="jconnectionFactory"
        class="org.springframework.data.redis.connection.jedis.JedisConnectionFactory"
        p:hostName="${redis.host}" p:port="${redis.port}" p:poolConfig-ref="jpoolConfig"/>

    <!-- Redis模版类，用于操作redis -->
    <bean id="redisTemplate" class="org.springframework.data.redis.core.RedisTemplate"
        p:connectionFactory-ref="jconnectionFactory">
    </bean>

</beans>

3）applicationContext.properties

#连接配置
redis.host=127.0.0.1
redis.port=6379


#连接池配置
redis.maxIdle=10
redis.maxWait=50
  #指明是否在从池中取出连接前进行检验,如果检验失败,则从池中去除连接并尝试取出另一个
redis.testOnBorrow=true 

4）User.java

package com.example.redis.entity;

import org.springframework.beans.factory.annotation.Autowired;

public class User
{
	@Autowired
	private long id;
	
	@Autowired
	private String name;

	public long getId()
	{
		return id;
	}

	public void setId(long id2)
	{
		this.id = id2;
	}

	public String getName()
	{
		return name;
	}

	public void setName(String name)
	{
		this.name = name;
	}	
	
}

5）UserDao.java

package com.example.redis.dao;

import java.io.Serializable;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.dao.DataAccessException;
import org.springframework.data.redis.connection.RedisConnection;
import org.springframework.data.redis.core.RedisCallback;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.stereotype.Repository;

import com.example.redis.entity.User;

@Repository
public class UserDao
{
	 @Autowired
	    protected RedisTemplate<Serializable, Serializable> redisTemplate;

	    public void saveUser(final User user) {
	        redisTemplate.execute(new RedisCallback<Object>() {

	            public Object doInRedis(RedisConnection connection) throws DataAccessException {

	                connection.set(redisTemplate.getStringSerializer().serialize(user.getId() + ""),
	                        redisTemplate.getStringSerializer().serialize(user.getName()));

	                return null;
	            }

	        });
	    }

	    public User getUser(final long id) {
	        return redisTemplate.execute(new RedisCallback<User>() {

	            public User doInRedis(RedisConnection connection) throws DataAccessException {
	                byte[] key = redisTemplate.getStringSerializer().serialize(id + "");
	                if (connection.exists(key)) {
	                    byte[] value = connection.get(key);
	                    String name = redisTemplate.getStringSerializer().deserialize(value);
	                    User user = new User();
	                    user.setName(name);
	                    user.setId(id);
	                    return user;
	                }
	                return null;
	            }

	        });
	    }

}

6）App.java

package com.example.redis.dao;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

import com.example.redis.entity.User;

public class App
{
	 @SuppressWarnings("resource")
	    public static void main( String[] args )
	    {
	        ApplicationContext ac =  new ClassPathXmlApplicationContext("classpath:/applicationContext.xml");	       
	        UserDao userDAO = (UserDao)ac.getBean("userDao");
	   
	        User user = new User();
	        user.setId(123);
	        user.setName("Lucky");
	       
	        userDAO.saveUser(user);	               
	        
	        User userr = userDAO.getUser(123); //与 id 对应
	        System.out.println(userr.getName());       
	       
	    }

}

7）Redis1.java

/*
 * 测试连接server成功否
 */
package com.example.redis.dao;

import redis.clients.jedis.Jedis;

public class Redis1
{
	public static void main(String[] args)
	{
		Jedis jedis = new Jedis("localhost");
		System.out.println("连接: " + jedis.ping());
	}

}

4. 运行

先跑Redis1.java  ->  测试连接是否成功

再跑App.java -> 结果：

ok！

5. 过程中，出现的问题&解决

1）pox.xml需要导入servlet和slf4j

2）Redis连接的是本地服务器，注意地址

3）Redis不用设置密码，注意有无设置密码