Spring Cache快速入门教程及案例

1. Spring Cache介绍

Spring Cache提供了一组注解，使开发者能够轻松地在方法上定义缓存行为

Spring Cache抽象了缓存的底层实现，允许开发者选择使用不同的缓存提供者（如 Ehcache、Redis、Caffeine 等）。通过配置相应的缓存管理器，可以方便地切换底层缓存实现，而无需改变应用代码

Spring Cache的maven坐标：

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-cache</artifactId>
    <version>3.1.5</version>
</dependency>

Spring Cache的常用注解：

2. Spring Cache入门案例

CacheDemoApplication.java

package com.itheima;

import lombok.extern.slf4j.Slf4j;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cache.annotation.EnableCaching;

@Slf4j
@SpringBootApplication
@EnableCaching
public class CacheDemoApplication {
    public static void main(String[] args) {
        SpringApplication.run(CacheDemoApplication.class, args);
        log.info("项目启动成功...");
    }
}

WebMvcConfiguration.java

@Configuration
@Slf4j
public class WebMvcConfiguration extends WebMvcConfigurationSupport {

    /**
     * 生成接口文档配置
     *
     * @return
     */
    @Bean
    public Docket docket() {
        log.info("准备生成接口文档...");

        ApiInfo apiInfo = new ApiInfoBuilder()
                .title("接口文档")
                .version("2.0")
                .description("接口文档")
                .build();

        Docket docket = new Docket(DocumentationType.SWAGGER_2)
                .apiInfo(apiInfo)
                .select()
                //指定生成接口需要扫描的包
                .apis(RequestHandlerSelectors.basePackage("com.itheima.controller"))
                .paths(PathSelectors.any())
                .build();

        return docket;
    }

    /**
     * 设置静态资源映射
     *
     * @param registry
     */
    protected void addResourceHandlers(ResourceHandlerRegistry registry) {
        log.info("开始设置静态资源映射...");
        registry.addResourceHandler("/doc.html").addResourceLocations("classpath:/META-INF/resources/");
        registry.addResourceHandler("/webjars/**").addResourceLocations("classpath:/META-INF/resources/webjars/");
    }
}

User.java

@Data
public class User implements Serializable {
    private static final long serialVersionUID = 1L;
    private Long id;
    private String name;
    private int age;
}

UserController.java

package com.itheima.controller;

import com.itheima.entity.User;
import com.itheima.mapper.UserMapper;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.cache.annotation.CacheEvict;
import org.springframework.cache.annotation.CachePut;
import org.springframework.cache.annotation.Cacheable;
import org.springframework.web.bind.annotation.*;

@RestController
@RequestMapping("/user")
@Slf4j
public class UserController {

    @Autowired
    private UserMapper userMapper;

    @PostMapping
    @CachePut(cacheNames = "userCache", key = "#user.id")
    // @CachePut(cacheNames = "userCache", key = "#result.id")
    // @CachePut(cacheNames = "userCache", key = "#p0.id")
    // @CachePut(cacheNames = "userCache", key = "#a0.id")
    // @CachePut(cacheNames = "userCache", key = "#root.args[0].id")
    public User save(@RequestBody User user){
        userMapper.insert(user);
        return user;
    }

    @Cacheable(cacheNames = "userCache", key = "#id")
    @GetMapping
    public User getById(Long id){
        User user = userMapper.getById(id);
        return user;
    }

    @DeleteMapping
    @CacheEvict(cacheNames = "userCache", key = "#id")
    public void deleteById(Long id){
        userMapper.deleteById(id);
    }

	@DeleteMapping("/delAll")
    @CacheEvict(cacheNames = "userCache", allEntries = true)
    public void deleteAll(){
        userMapper.deleteAll();
    }
}

UserMapper.java

@Mapper
public interface UserMapper {

    @Insert("insert into user(name,age) values (#{name}, #{age})")
    @Options(useGeneratedKeys = true, keyProperty = "id")
    void insert(User user);

    @Delete("delete from user where id = #{id}")
    void deleteById(Long id);

    @Delete("delete from user")
    void deleteAll();

    @Select("select * from user where id = #{id}")
    User getById(Long id);
}

application.yml

server:
  port: 8888
spring:
  datasource:
    druid:
      driver-class-name: com.mysql.cj.jdbc.Driver
      url: jdbc:mysql://localhost:13306/spring_cache_demo?serverTimezone=Asia/Shanghai&useUnicode=true&characterEncoding=utf-8&zeroDateTimeBehavior=convertToNull&useSSL=false&allowPublicKeyRetrieval=true
      username: root
      password: root
  redis:
    host: localhost
    port: 6379
    password: 123456
    database: 1
logging:
  level:
    com:
      itheima:
        mapper: debug
        service: info
        controller: info

pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<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>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.7.3</version>
        <relativePath/>
    </parent>
    <groupId>com.itheima</groupId>
    <artifactId>springcache-demo</artifactId>
    <version>1.0-SNAPSHOT</version>

    <properties>
        <maven.compiler.source>11</maven.compiler.source>
        <maven.compiler.target>11</maven.compiler.target>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
            <scope>compile</scope>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.18.20</version>
        </dependency>

        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>1.2.76</version>
        </dependency>

        <dependency>
            <groupId>commons-lang</groupId>
            <artifactId>commons-lang</artifactId>
            <version>2.6</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-cache</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-redis</artifactId>
        </dependency>

        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <scope>runtime</scope>
        </dependency>

        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>2.2.0</version>
        </dependency>

        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid-spring-boot-starter</artifactId>
            <version>1.2.1</version>
        </dependency>

        <dependency>
            <groupId>com.github.xiaoymin</groupId>
            <artifactId>knife4j-spring-boot-starter</artifactId>
            <version>3.0.2</version>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
        </dependency>
    </dependencies>
    
    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <version>2.7.3</version>
            </plugin>
        </plugins>
    </build>
</project>