Hazelcast with Spring Boot

Hazelcast is a distributed computation and storage platform for consistently low-latency querying, aggregation and stateful computation against event streams and traditional data sources. It allows you to quickly build resource-efficient, real-time applications. You can deploy it at any scale from small edge devices to a large cluster of cloud instances.

Add the following dependencies to your Spring Boot Server project’s pom.xml file:

<dependency>
    <groupId>com.hazelcast</groupId>
    <artifactId>hazelcast-spring</artifactId>
    <version>5.0.1</version>
</dependency>
<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-cache</artifactId>
</dependency>

@Configuration
public class HazelcastConfig {
    @Bean
    @Profile("local")
    public Config eurekaConfig() {
        var mapConfig=new MapConfig()
                .setName("default")
                .setTimeToLiveSeconds(30);

        var config = new Config();
        config.getNetworkConfig().setPort(5701);
        config.getNetworkConfig().getJoin().getMulticastConfig().setEnabled(true);
        config.setClusterName("localhost");
        config.setInstanceName("localInstance");
        config.addMapConfig(mapConfig);
        return config;
    }
}

Inside your Spring Boot Client Application add following maven dependencies and annotate the methods or classes that you want to cache with the Spring Cache annotations, for example:

<dependency>
    <groupId>com.hazelcast</groupId>
    <artifactId>hazelcast-client</artifactId>
    <version>{hazelcast-version}</version>
</dependency>
<dependency>
    <groupId>com.hazelcast</groupId>
    <artifactId>hazelcast-spring</artifactId>
    <version>{hazelcast-version}</version>
</dependency>

-- Other dependencies e.g. spring boot cache

@Bean
public HazelcastInstance hazelcastInstance() {
    ClientConfig config = new ClientConfig();
    config.getNetworkConfig().addAddress("remote-address");
    return HazelcastClient.newHazelcastClient(config);
}

@Configuration
@EnableCaching
public class CacheConfig extends CachingConfigurerSupport {

    @Autowired
    private HazelcastInstance hazelcastInstance;

    @Override
    public CacheManager cacheManager() {
        return new HazelcastCacheManager(hazelcastInstance);
    }
}

@Service
public class MyService {

    @Cacheable("myCache")
    public Object getCachedObject(String key) {
        // retrieve object from database or other source
        return object;
    }

    @CachePut("myCache")
    public void updateCachedObject(String key, Object object) {
        // update object in database or other source
    }

    @CacheEvict("myCache")
    public void evictCachedObject(String key) {
        // remove object from database or other source
    }
}

That’s it folks!

Happy Coding!