Spring Boot Hazelcast Caching 使用和配置

本文将展示spring boot 结合 Hazelcast 的缓存使用案例。

1. Project Structure

2. Maven Dependencies

<?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>

    <groupId>com.zzf</groupId>
    <artifactId>spring-boot-hazelcast</artifactId>
    <version>1.0-SNAPSHOT</version>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.0.1.RELEASE</version>
    </parent>

    <dependencies>

        <!--  spring boot   -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-cache</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <!-- hazelcast jar  -->
        <dependency>
            <groupId>com.hazelcast</groupId>
            <artifactId>hazelcast-all</artifactId>
            <version>3.10.1</version>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>
</project>

3. Hazelcast Caching Service

通过使用
@cachable注释来注释play方法，将缓存后续调用的结果。
@CacheEvict(allEntries=true)清除缓存中的所有条目。
@CacheConfig(cachenames=”instruments”)注册了带有指定缓存的spring框架缓存注释的所有方法。

@Service
@CacheConfig(cacheNames = "instruments")
public class MusicService {

    private static Logger log = LoggerFactory.getLogger(MusicService.class);
    @CacheEvict(allEntries = true)
    public void clearCache(){}

    // 表示的是属性为 trombone 就进行缓存
    @Cacheable(condition = "#instrument.equals('trombone')")
    public String play(String instrument){

        log.info("Executing: " + this.getClass().getSimpleName() + ".play(\"" + instrument + "\");");
        return "playing " + instrument + "!";
    }
}

4. Hazelcast Caching Configuration

如果类路径下存在hazelcast, spring boot 将会自动创建Hazelcast 的实例。
下面将介绍两种加载的方式：

• 使用java 配置的方式
• 使用hazelcast.xml XML 的配置

4.1 Hazelcast Java Configuration

@Configuration
public class HazelcastConfiguration {
    @Bean
    public Config hazelcastConfig(){
        return new Config().setInstanceName("hazelcast-instance")
                .addMapConfig(
                            new MapConfig()
                                    .setName("instruments")
                                    .setMaxSizeConfig(new MaxSizeConfig(200, MaxSizeConfig.MaxSizePolicy.FREE_HEAP_SIZE))
                                    .setEvictionPolicy(EvictionPolicy.LRU)
                                    .setTimeToLiveSeconds(20)
                );
    }
}

4.2 Hazelcast XML Configuration

可以使用xml 配置 Hazelcast , 在src/main/resources 添加一个文件hazelcast.xml
spring boot 将会自动注入配置文件， 当然也可以指定路径路径, 使用属性spring.hazelcast.config 配置在yml 或者properties 文件中， 例如下面所示：

<?xml version="1.0" encoding="UTF-8"?>
<hazelcast
        xsi:schemaLocation="http://www.hazelcast.com/schema/config http://www.hazelcast.com/schema/config/hazelcast-config.xsd"
        xmlns="http://www.hazelcast.com/schema/config"
        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">

    <map name="instruments">
        <max-size>200</max-size>
        <eviction-policy>LFU</eviction-policy>
        <time-to-live-seconds>20</time-to-live-seconds>
    </map>
</hazelcast>

具体的application.properties 和 application.yml 文件显示

# application.yml
spring:
  hazelcast:
    config: classpath:config/hazelcast.xml

# application.properties
spring.hazelcast.config=classpath:config/hazelcast.xml

5. 访问controller

@Controller
public class HazelcastController {

    private Logger logger = LoggerFactory.getLogger(HazelcastController.class);

    @Autowired
    private MusicService musicService;

    @Autowired
    private CacheManager cacheManager;

    @RequestMapping("/hezelcast")
    @ResponseBody
    public void getHazelcast(){

        logger.info("Spring Boot Hazelcast Caching Example Configuration");
        logger.info("Using cache manager: " + cacheManager.getClass().getName());

        // 清空缓存
        musicService.clearCache();

        // 调用方法
        play("trombone");
        play("guitar");

        play("trombone");
        play("guitar");

        play("bass");
        play("trombone");
    }

    private void play(String instrument){
        logger.info("Calling: " + MusicService.class.getSimpleName() + ".play(\"" + instrument + "\");");
        musicService.play(instrument);
    }
}

6. Bootstrap Hazelcast Caching Application

使用注解@EnableCaching 开启缓存机制.

@EnableCaching
@SpringBootApplication
public class HazelcastApplication{

    private Logger logger = LoggerFactory.getLogger(HazelcastApplication.class);

    public static void main(String[] args) {
        SpringApplication.run(HazelcastApplication.class, args);
    }
}

7. 访问和解释

2018-06-02 22:15:18.488  INFO 41728 --- [nio-8080-exec-4] c.h.i.p.impl.PartitionStateManager       : [192.168.1.1]:5701 [dev] [3.10.1] Initializing cluster partition table arrangement...
2018-06-02 22:15:18.521  INFO 41728 --- [nio-8080-exec-4] c.z.s.h.controller.HazelcastController   : Calling: MusicService.play("trombone");
2018-06-02 22:15:18.558  INFO 41728 --- [nio-8080-exec-4] c.z.s.hazelcast.service.MusicService     : Executing: MusicService.play("trombone");
2018-06-02 22:15:18.563  INFO 41728 --- [nio-8080-exec-4] c.z.s.h.controller.HazelcastController   : Calling: MusicService.play("guitar");
2018-06-02 22:15:18.563  INFO 41728 --- [nio-8080-exec-4] c.z.s.hazelcast.service.MusicService     : Executing: MusicService.play("guitar");
2018-06-02 22:15:18.563  INFO 41728 --- [nio-8080-exec-4] c.z.s.h.controller.HazelcastController   : Calling: MusicService.play("trombone");
2018-06-02 22:15:18.564  INFO 41728 --- [nio-8080-exec-4] c.z.s.h.controller.HazelcastController   : Calling: MusicService.play("guitar");
2018-06-02 22:15:18.565  INFO 41728 --- [nio-8080-exec-4] c.z.s.hazelcast.service.MusicService     : Executing: MusicService.play("guitar");
2018-06-02 22:15:18.565  INFO 41728 --- [nio-8080-exec-4] c.z.s.h.controller.HazelcastController   : Calling: MusicService.play("bass");
2018-06-02 22:15:18.565  INFO 41728 --- [nio-8080-exec-4] c.z.s.hazelcast.service.MusicService     : Executing: MusicService.play("bass");
2018-06-02 22:15:18.566  INFO 41728 --- [nio-8080-exec-4] c.z.s.h.controller.HazelcastController   : Calling: MusicService.play("trombone");

从上面的可以看到 只有trombone ， 才会直接访问缓存信息， 正是在MusicService 类中的方法play 上时候注解进行过滤：
@Cacheable(condition = “#instrument.equals(‘trombone’)”)

本文参考地址：
https://memorynotfound.com/spring-boot-hazelcast-caching-example-configuration/