SSM框架中使用Redis单机版

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上一篇文章就说要尝试在代码中实现Redis使用，但是有一段时间很（tou）忙（lan），所以现在才写。

Maven依赖

<!-- Redis -->
<dependency>
    <groupId>redis.clients</groupId>
    <artifactId>jedis</artifactId>
    <version>2.9.0</version>
</dependency>

<dependency>
    <groupId>org.springframework.data</groupId>
    <artifactId>spring-data-redis</artifactId>
    <version>1.7.1.RELEASE</version>
</dependency>

配置文件

config.properties:

#Redis config
redis.host=localhost
redis.port=6379

spring-jedis.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:context="http://www.springframework.org/schema/context" xmlns:p="http://www.springframework.org/schema/p"
       xmlns:aop="http://www.springframework.org/schema/aop" xmlns:tx="http://www.springframework.org/schema/tx"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
    http://www.springframework.org/schema/beans/spring-beans-4.2.xsd">
    <!-- 连接池配置 -->
    <bean id="jedisPoolConfig" class="redis.clients.jedis.JedisPoolConfig">
        <!-- 最大连接数 -->
        <property name="maxTotal" value="30" />
        <!-- 最大空闲连接数 -->
        <property name="maxIdle" value="10" />
        <!-- 每次释放连接的最大数目 -->
        <property name="numTestsPerEvictionRun" value="1024" />
        <!-- 释放连接的扫描间隔（毫秒） -->
        <property name="timeBetweenEvictionRunsMillis" value="30000" />
        <!-- 连接最小空闲时间 -->
        <property name="minEvictableIdleTimeMillis" value="1800000" />
        <!-- 连接空闲多久后释放, 当空闲时间>该值 且 空闲连接>最大空闲连接数 时直接释放 -->
        <property name="softMinEvictableIdleTimeMillis" value="10000" />
        <!-- 获取连接时的最大等待毫秒数,小于零:阻塞不确定的时间,默认-1 -->
        <property name="maxWaitMillis" value="1500" />
        <!-- 在获取连接的时候检查有效性, 默认false -->
        <property name="testOnBorrow" value="true" />
        <!-- 在空闲时检查有效性, 默认false -->
        <property name="testWhileIdle" value="true" />
        <!-- 连接耗尽时是否阻塞, false报异常,ture阻塞直到超时, 默认true -->
        <property name="blockWhenExhausted" value="false" />
    </bean>
    <!-- jedis客户端单机版 -->
    <bean id="redisClient" class="redis.clients.jedis.JedisPool">
        <constructor-arg name="host" value="${redis.host}"/>
        <constructor-arg name="port" value="${redis.port}"/>
        <constructor-arg name="poolConfig" ref="jedisPoolConfig"/>
    </bean>

</beans>

配置简单的API

演示简单的使用，所以很多异常状态没有设置。
创建一个接口和接口实现类。
IJedisClientService：

package cn.sevenyuan.demo.cache;

/**
 * Created by JingQ on 2017/9/15.
 */
public interface IJedisClientService {

    String get(String key);

    String set(String key, String value);

    String hget(String hkey, String key);

    boolean exist(String key);

    long hset(String hkey, String key, String value);

    long incr(String key);

    long expire(String key, int second);

    long ttl(String key);

    long del(String key);

    long hdel(String hkey, String key);
}

JedsiClientService:

package cn.sevenyuan.demo.cache;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import redis.clients.jedis.Jedis;
import redis.clients.jedis.JedisPool;

/**
 * Created by JingQ on 2017/9/15.
 */
@Service
public class JedisClientService implements IJedisClientService{

    @Autowired
    private JedisPool jedisPool;

    @Override
    public String get(String key) {
        Jedis jedis = jedisPool.getResource();
        String string = jedis.get(key);
        jedis.close();
        return string;
    }

    @Override
    public String set(String key, String value) {
        Jedis jedis = jedisPool.getResource();
        String string = jedis.set(key, value);
        jedis.close();
        return string;
    }

    @Override
    public String hget(String hkey, String key) {
        Jedis jedis = jedisPool.getResource();
        String string = jedis.hget(hkey, key);
        jedis.close();
        return string;
    }

    @Override
    public boolean exist(String key) {
        Jedis jedis = jedisPool.getResource();
        boolean result = jedis.exists(key);
        jedis.close();
        return result;
    }

    @Override
    public long hset(String hkey, String key, String value) {
        Jedis jedis = jedisPool.getResource();
        Long result = jedis.hset(hkey, key, value);
        jedis.close();
        return result;
    }

    @Override
    public long incr(String key) {
        Jedis jedis = jedisPool.getResource();
        Long result = jedis.incr(key);
        jedis.close();
        return result;
    }

    @Override
    public long expire(String key, int second) {
        Jedis jedis = jedisPool.getResource();
        Long result = jedis.expire(key, second);
        jedis.close();
        return result;
    }

    @Override
    public long ttl(String key) {
        Jedis jedis = jedisPool.getResource();
        Long result = jedis.ttl(key);
        jedis.close();
        return result;
    }

    @Override
    public long del(String key) {
        Jedis jedis = jedisPool.getResource();
        Long result = jedis.del(key);
        jedis.close();
        return result;
    }

    @Override
    public long hdel(String hkey, String key) {
        Jedis jedis = jedisPool.getResource();
        Long result = jedis.hdel(hkey, key);
        jedis.close();
        return result;
    }
}

进行调用

demo使用的是mysql作为最终结果保存，redis作为缓存调用，一般的套路是查询到的结果放进redis中，设置过期时间，在数据更新或者删除，将这个key值删掉，重新设置。

例：图书的增删查改

package cn.sevenyuan.demo.service.impl;

import cn.sevenyuan.demo.cache.IJedisClientService;
import cn.sevenyuan.demo.dao.IBookDao;
import cn.sevenyuan.demo.domain.Book;
import cn.sevenyuan.demo.service.IBookService;
import cn.sevenyuan.demo.utils.RedisKeyUtils;
import com.alibaba.fastjson.JSONObject;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.util.CollectionUtils;
import org.springframework.util.ObjectUtils;

import java.util.Collections;
import java.util.List;

/**
 * RedisKeyUtils是自己写的key值生成器，按照个人命名习惯去写
 * Created by JingQ on 2017/9/5.
 */
@Service("bookService")
public class BookService implements IBookService {
    private final String className = "BookService";
    @Autowired
    private IBookDao bookDao;

    @Autowired
    private IJedisClientService jedisClientService;

    @Override
    public Book selectBookById(Integer id) {
        String key = RedisKeyUtils.generateKey(className, "book", String.valueOf(id));
        boolean isExist = jedisClientService.exist(key);
        Book book = null;
        if (isExist){
            String result = jedisClientService.get(key);
            book = JSONObject.parseObject(result, Book.class);
        }else {
            book = bookDao.selectById(id);
            if (!ObjectUtils.isEmpty(book)){
                jedisClientService.set(key, JSONObject.toJSON(book).toString());
            }
        }
        return book;
    }

    @Override
    public int insert(Book book) {
        if (ObjectUtils.isEmpty(book)){
            return 0;
        }
        return bookDao.insert(book);
    }

    @Override
    public int deleteByPrimaryKey(Integer id) {
        String key = RedisKeyUtils.generateKey(className, "book", String.valueOf(id));
        if (jedisClientService.exist(key)){
            jedisClientService.del(key);
        }
        return bookDao.deleteByPrimaryId(id);
    }

    @Override
    public int updateByPrimaryKey(Book book) {
        if (ObjectUtils.isEmpty(book)){
            return 0;
        }
        String key = RedisKeyUtils.generateKey(className, "book", String.valueOf(book.getBookId()));
        if (jedisClientService.exist(key)){
            jedisClientService.del(key);
        }
        return bookDao.updateByPrimaryId(book);
    }

    @Override
    public List<Book> selectBookByIds(List<Integer> list) {
        if (CollectionUtils.isEmpty(list)){
            Collections.emptyList();
        }
        return bookDao.selectByIds(list);
    }
}

单机版使用基本就是这个套路了，最近还在看ZooKeeper和简单的jvm，之后也会记录一下学习的内容~