Spring Boot缓存技术（ehcache、SpringData Redis）
- SpringBoot 整合 Ehcache
- SpringBoot 整合 SpringDataRedis
一、SpringBoot 整合 Ehcache
1、导入相关maven依赖
4.0.0
org.springframework.boot
spring-boot-starter-parent
1.5.10.RELEASE
com.bjsxt
23-spring-boot-ehcache
0.0.1-SNAPSHOT
1.7
3.0.2.RELEASE
2.0.4
org.springframework.boot
spring-boot-starter-web
org.springframework.boot
spring-boot-starter-thymeleaf
org.springframework.boot
spring-boot-starter-data-jpa
org.springframework.boot
spring-boot-starter-test
mysql
mysql-connector-java
com.alibaba
druid
1.0.9
org.springframework.boot
spring-boot-starter-cache
net.sf.ehcache
ehcache
2、创建 Ehcache 的配置文件
3、修改 application.properties 文件
spring.datasource.driverClassName=com.mysql.jdbc.Driver
spring.datasource.url=jdbc:mysql://localhost:3306/ssm
spring.datasource.username=root
spring.datasource.password=root
spring.datasource.type=com.alibaba.druid.pool.DruidDataSource
#spring data 正向工程
spring.jpa.hibernate.ddl-auto=update
#显示sql
spring.jpa.show-sql=true
#配置ehcache
spring.cache.ehcache.cofnig=ehcache.xml
4、修改启动类，在启动类上面添加@EnableCaching
package com.bjsxt;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cache.annotation.EnableCaching;
@SpringBootApplication
@EnableCaching
public class App {
public static void main(String[] args) {
SpringApplication.run(App.class, args);
}
}
5、创建业务层
package com.bjsxt.service;
import java.util.List;
import org.springframework.data.domain.Page;
import org.springframework.data.domain.Pageable;
import com.bjsxt.pojo.Users;
public interface UsersService {
List findUserAll();
Users findUserById(Integer id);
Page findUserByPage(Pageable pageable);
void saveUsers(Users users);
}
package com.bjsxt.service.impl;
import java.util.List;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.cache.annotation.CacheEvict;
import org.springframework.cache.annotation.Cacheable;
import org.springframework.data.domain.Page;
import org.springframework.data.domain.Pageable;
import org.springframework.stereotype.Service;
import com.bjsxt.dao.UsersRepository;
import com.bjsxt.pojo.Users;
import com.bjsxt.service.UsersService;
/**
* UsersService接口实现类
*
*
*/
@Service
public class UsersServiceImpl implements UsersService {
@Autowired
private UsersRepository usersRepository;
@Override
@Cacheable(value = "users")
public List findUserAll() {
return this.usersRepository.findAll();
}
@Override
//@Cacheable:对当前查询的对象做缓存处理
@Cacheable(value="users") //value对应自定义缓存策略的name
public Users findUserById(Integer id) {
return this.usersRepository.findOne(id);
}
}
6、修改实体类
package com.bjsxt.pojo;
import java.io.Serializable;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.Table;
@Entity
@Table(name="t_users")
public class Users implements Serializable {
@Id
@GeneratedValue(strategy=GenerationType.IDENTITY)
@Column(name="id")
private Integer id;
@Column(name="name")
private String name;
@Column(name="age")
private Integer age;
@Column(name="address")
private String address;
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public Integer getAge() {
return age;
}
public void setAge(Integer age) {
this.age = age;
}
public String getAddress() {
return address;
}
public void setAddress(String address) {
this.address = address;
}
@Override
public String toString() {
return "Users [id=" + id + ", name=" + name + ", age=" + age + ", address=" + address + "]";
}
}
7、测试
@Autowired
private UsersService usersService;
@Test
public void testFindUserById(){
//第一次查询
System.out.println(this.usersService.findUserById(1));
//第二次查询
System.out.println(this.usersService.findUserById(1));
}
二、@Cacheable 与@CacheEvict
1、@Cacheable
@Cacheable 作用：把方法的返回值添加到 Ehcache 中做缓存
Value 属性：指定一个 Ehcache 配置文件中的缓存策略，如果么有给定 value，name 则 表示使用默认的缓存策略
Key 属性：给存储的值起个名称。在查询时如果有名称相同的，那么则知己从缓存中将 数据返回
1.1、业务层
@Override
@Cacheable(value = "users",key = "#pageable.pageSize")
public Page findUserByPage(Pageable pageable) {
return this.usersRepository.findAll(pageable);
}
1.2、测试代码
@Test
public void testFindUserByPage(){
Pageable pageable=new PageRequest(0,2);
//第一次查询
System.out.println(this.usersService.findUserByPage(pageable).getTotalElements());
//第二次查询
System.out.println(this.usersService.findUserByPage(pageable).getTotalElements());
//第三次查询
pageable=new PageRequest(1,2);
System.out.println(this.usersService.findUserByPage(pageable).getTotalElements());
}
2、@CacheEvict
@CacheEvict 作用：清除缓存
2.1、业务层
package com.bjsxt.service.impl;
import java.util.List;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.cache.annotation.CacheEvict;
import org.springframework.cache.annotation.Cacheable;
import org.springframework.data.domain.Page;
import org.springframework.data.domain.Pageable;
import org.springframework.stereotype.Service;
import com.bjsxt.dao.UsersRepository;
import com.bjsxt.pojo.Users;
import com.bjsxt.service.UsersService;
/**
* UsersService接口实现类
*
*
*/
@Service
public class UsersServiceImpl implements UsersService {
@Autowired
private UsersRepository usersRepository;
@Override
@Cacheable(value = "users")
public List findUserAll() {
return this.usersRepository.findAll();
}
@Override
//@Cacheable:对当前查询的对象做缓存处理
@Cacheable(value="users") //value对应自定义缓存策略的name
public Users findUserById(Integer id) {
return this.usersRepository.findOne(id);
}
@Override
@Cacheable(value = "users",key = "#pageable.pageSize")
public Page findUserByPage(Pageable pageable) {
return this.usersRepository.findAll(pageable);
}
@Override
@CacheEvict(value = "users",allEntries = true)//清除缓存中以users缓存策略缓存的对象
public void saveUsers(Users users) {
this.usersRepository.save(users);
}
}
2.2、测试代码
@Test
public void testFindAll(){
//第一次查询
System.out.println(usersService.findUserAll().size());
Users users=new Users();
users.setAddress("南京");
users.setAge(43);
users.setName("朱七");
this.usersService.saveUsers(users);
//第二次查询
System.out.println(usersService.findUserAll().size());
}
三、SpringBoot 整合 SpringDataRedis
Redis 版本：3.2.1
运行环境：windows
1、SpringBoot 整合 SpringDataRedis
SpringDataRedis 是属于 SpringData 下的一个模块。作用就是简化对于 redis 的操作
1.1、修改 pom 文件添加 SpringDataRedis 的坐标
4.0.0
org.springframework.boot
spring-boot-starter-parent
1.5.10.RELEASE
com.bjsxt
24-spring-boot-redis
0.0.1-SNAPSHOT
1.7
3.0.2.RELEASE
2.0.4
org.springframework.boot
spring-boot-starter-web
org.springframework.boot
spring-boot-starter-thymeleaf
org.springframework.boot
spring-boot-starter-data-redis
org.springframework.boot
spring-boot-starter-test
1.2、编写 SpringDataRedis 的配置类（重点）
package com.bjsxt.config;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.redis.connection.jedis.JedisConnectionFactory;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.data.redis.serializer.StringRedisSerializer;
import redis.clients.jedis.JedisPoolConfig;
/**
* 完成对Redis的整合的一些配置
*
*
*/
@Configuration
public class RedisConfig {
/**
* 1.创建JedisPoolConfig对象。在该对象中完成一些链接池配置
* @ConfigurationProperties:会将前缀相同的内容创建一个实体
*/
@Bean
@ConfigurationProperties(prefix = "spring.redis.pool")
public JedisPoolConfig jedisPoolConfig(){
JedisPoolConfig config = new JedisPoolConfig();
//最大空闲数
config.setMaxIdle(10);
//最小空闲数
config.setMinIdle(5);
//最大链接数
config.setMaxTotal(20);
System.out.println("默认值"+config.getMaxIdle());
System.out.println("默认值"+config.getMinIdle());
System.out.println("默认值"+config.getMaxTotal());
return config;
}
/**
* 2.创建JedisConnectionFactory：配置redis链接信息
*/
@Bean
@ConfigurationProperties(prefix = "spring.redis")
public JedisConnectionFactory jedisConnectionFactory(JedisPoolConfig config){
System.out.println("配置完毕"+config.getMaxIdle());
System.out.println("配置完毕"+config.getMinIdle());
System.out.println("配置完毕"+config.getMaxTotal());
JedisConnectionFactory factory = new JedisConnectionFactory();
//关联链接池的配置对象
factory.setPoolConfig(config);
//配置链接Redis的信息
//主机地址
factory.setHostName("127.0.0.1");
//端口
factory.setPort(6379);
return factory;
}
/**
* 3.创建RedisTemplate:用于执行Redis操作的方法
*/
@Bean
public RedisTemplate redisTemplate(JedisConnectionFactory factory){
RedisTemplate template = new RedisTemplate<>();
//关联
template.setConnectionFactory(factory);
//为key设置序列化器
template.setKeySerializer(new StringRedisSerializer());
//为value设置序列化器
template.setValueSerializer(new StringRedisSerializer());
return template;
}
}
1.3、编写测试代码，测试整合环境
1.3.1、编写测试类
@Autowired
private RedisTemplate redisTemplate;
//添加一个字符串
@Test
public void testSet(){
this.redisTemplate.opsForValue().set("key","青衫");
}
//取出一个字符串
@Test
public void testGet(){
String value= (String) this.redisTemplate.opsForValue().get("key");
System.out.println(value);
}
2、提取 redis 的配置信息
2.1、在 src/main/resource/ 目录下新建一个配置文件:application.properties
#最大空闲数
spring.redis.pool.max-idle=10
#最小空闲数
spring.redis.pool.min-idle=5
#最大链接数
spring.redis.pool.max-total=20
#主机ip
spring.redis.host=127.0.0.1
#redis端口
spring.redis.port=6379
2.2、修改redis配置类
package com.bjsxt.config;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.redis.connection.jedis.JedisConnectionFactory;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.data.redis.serializer.StringRedisSerializer;
import redis.clients.jedis.JedisPoolConfig;
/**
* 完成对Redis的整合的一些配置
*
*
*/
@Configuration
public class RedisConfig {
/**
* 1.创建JedisPoolConfig对象。在该对象中完成一些链接池配置
* @ConfigurationProperties:会将前缀相同的内容创建一个实体
*/
@Bean
@ConfigurationProperties(prefix = "spring.redis.pool")
public JedisPoolConfig jedisPoolConfig(){
JedisPoolConfig config = new JedisPoolConfig();
System.out.println("默认值"+config.getMaxIdle());
System.out.println("默认值"+config.getMinIdle());
System.out.println("默认值"+config.getMaxTotal());
return config;
}
/**
* 2.创建JedisConnectionFactory：配置redis链接信息
*/
@Bean
@ConfigurationProperties(prefix = "spring.redis")
public JedisConnectionFactory jedisConnectionFactory(JedisPoolConfig config){
System.out.println("配置完毕"+config.getMaxIdle());
System.out.println("配置完毕"+config.getMinIdle());
System.out.println("配置完毕"+config.getMaxTotal());
JedisConnectionFactory factory = new JedisConnectionFactory();
//关联链接池的配置对象
factory.setPoolConfig(config);
return factory;
}
/**
* 3.创建RedisTemplate:用于执行Redis操作的方法
*/
@Bean
public RedisTemplate redisTemplate(JedisConnectionFactory factory){
RedisTemplate template = new RedisTemplate<>();
//关联
template.setConnectionFactory(factory);
//为key设置序列化器
template.setKeySerializer(new StringRedisSerializer());
//为value设置序列化器
template.setValueSerializer(new StringRedisSerializer());
return template;
}
}
3、SpringDataRedis 操作实体对象
3.1.1、创建实体类
/**
* Copyright (C), 2015-2019, XXX有限公司
* FileName: Users
* Author: admin
* Date: 2019/5/24 11:25
* Description:
* History:
*
3.1.2、测试代码
/**
* 添加一个Users对象
*/
@Test
public void testSetUsers(){
Users users=new Users();
users.setAge(20);
users.setName("张三丰");
users.setId(1);
//存的时候，要重新设置序列化器
this.redisTemplate.setValueSerializer(new JdkSerializationRedisSerializer());
this.redisTemplate.opsForValue().set("users",users);
}
/**
* 取Users对象
*/
@Test
public void testGetUsers(){
//取的操作，必须重新设置序列化器
this.redisTemplate.setValueSerializer(new JdkSerializationRedisSerializer());
Users users= (Users) this.redisTemplate.opsForValue().get("users");
System.out.println(users);
}
4、SpringDataRedis 以 JSON 格式存储实体对象
4.1、测试代码
/**
* 基于JSON格式存Users对象
*/
@Test
public void testSetUsersUseJSON(){
Users users=new Users();
users.setAge(20);
users.setName("李四丰");
users.setId(1);
this.redisTemplate.setValueSerializer(new Jackson2JsonRedisSerializer<>(Users.class));
this.redisTemplate.opsForValue().set("users_json",users);
}
/**
* 基于JSON格式取Users对象
*/
@Test
public void testGetUseJSON(){
//反序列化
this.redisTemplate.setValueSerializer(new Jackson2JsonRedisSerializer<>(Users.class));
Users users= (Users) this.redisTemplate.opsForValue().get("users_json");
System.out.println(users);
}