Hazelcast IMDG (In-Memory Data Grid) is a distributed computing platform that provides high-performance in-memory data storage and processing. It allows developers to cache and share data across multiple servers, enhancing the performance and scalability of applications.

In this blog post, we will explore the integration of Hazelcast IMDG with Spring Boot to leverage its powerful caching capabilities within Java applications.

Setting Up Hazelcast IMDG Spring Boot Integration

To integrate Hazelcast IMDG with Spring Boot, we need to add the spring-boot-starter-cache dependency, which provides Spring’s cache abstraction. Additionally, we need to include the hazelcast-spring dependency for the Hazelcast IMDG integration.

Maven Configuration

In your pom.xml, add the following dependencies:

<dependencies>
    <!-- Spring Boot Starter Cache -->
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-cache</artifactId>
    </dependency>
    
    <!-- Hazelcast Spring Integration -->
    <dependency>
        <groupId>com.hazelcast</groupId>
        <artifactId>hazelcast-spring</artifactId>
    </dependency>
</dependencies>

Configuring Hazelcast IMDG

Next, we need to configure Hazelcast IMDG properties in application.properties or application.yml file.

For example, in application.properties:

# Hazelcast IMDG Configuration
spring.cache.type=hazelcast
hazelcast.config=classpath:hazelcast.xml

The spring.cache.type property is set to hazelcast, enabling Hazelcast as the caching provider. The hazelcast.config property specifies the location of the Hazelcast configuration file.

Hazelcast Configuration File

Create a hazelcast.xml file in the src/main/resources directory to define the Hazelcast IMDG configuration. Use the following example as a starting point:

<hazelcast xsi:schemaLocation="http://www.hazelcast.com/schema/config hazelcast-config-4.1.xsd"
            xmlns="http://www.hazelcast.com/schema/config"
            xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">

    <!-- Hazelcast Cluster Configuration -->
    <network>
        <join>
            <multicast enabled="false"/>
            <tcp-ip enabled="true">
                <member>localhost</member>
            </tcp-ip>
        </join>
    </network>

    <!-- Hazelcast Map Configuration -->
    <map name="myCache">
        <time-to-live-seconds>300</time-to-live-seconds>
    </map>

</hazelcast>

The network section defines the cluster configuration. In this example, we use a single member cluster running on localhost. Adjust this configuration according to your requirements.

The map section defines a cache named myCache and sets its time-to-live to 300 seconds (5 minutes).

Using Hazelcast IMDG Spring Boot Integration

Once the configuration is in place, we can leverage Hazelcast IMDG caching capabilities within our Spring Boot application.

Caching Annotations

Spring’s caching annotations @Cacheable, @CachePut, and @CacheEvict can be used to control the caching behavior. By annotating methods with these annotations, Spring will automatically manage the cache entries.

Here’s an example of using @Cacheable to cache the result of a method for subsequent invocations:

@Service
public class MyService {

    @Cacheable("myCache")
    public String getData(String key) {
        // ... logic to fetch data
        return "Data for key: " + key;
    }
}

In this example, the getData method’s response will be cached using the Hazelcast IMDG cache named myCache. For subsequent invocations, the method will be bypassed, and the cached result will be returned.

Cache Management and Monitoring

Hazelcast IMDG provides a management center that allows you to monitor and manage your caches. You can access the management center by navigating to http://localhost:8080/hazelcast-mancenter when running your Spring Boot application.

Conclusion

Hazelcast IMDG Spring Boot integration provides a seamless way to leverage the power of in-memory caching within your Java applications. By configuring and using Hazelcast’s caching capabilities, you can improve the performance and scalability of your applications.

Whether you are working on a small-scale or large-scale distributed system, Hazelcast IMDG can be a valuable addition to your tech stack.

Give it a try and experience the benefits of in-memory data grids with Hazelcast and Spring Boot!

#hazelcast #springboot #caching #distributedcomputing