In today’s tech world, where high performance and scalability are essential requirements, distributed caching plays a vital role in achieving these goals. Caching data in a distributed environment helps to reduce data retrieval time and improve system responsiveness. In this article, we will explore how to implement distributed caching using two popular Java caching frameworks - Oracle Coherence and Hazelcast.

What is Distributed Caching?

Distributed caching is a technique where data is cached across multiple nodes in a distributed system. It allows applications to store frequently accessed data closer to the application, reducing the need to retrieve it from a remote data source. This results in faster data retrieval, improved application performance, and reduced network latency.

Oracle Coherence

Oracle Coherence is an in-memory data grid solution that enables distributed caching and data management. It provides a highly scalable and fault-tolerant caching infrastructure. Let’s see how we can implement distributed caching using Oracle Coherence in Java.

1. First, we need to include the Oracle Coherence dependency in our project. We can do this by adding the following Maven dependency to our pom.xml file:

<dependency>
    <groupId>com.oracle.coherence</groupId>
    <artifactId>coherence</artifactId>
    <version>XX.X.X</version>
</dependency>

1. Next, we need to configure Oracle Coherence in our Java application. We can do this by creating a cache-config.xml file and specifying the cache configuration details. Here’s an example configuration:

<?xml version="1.0"?>

<cache-config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
              xmlns="http://xmlns.oracle.com/coherence/coherence-cache-config"
              xsi:schemaLocation="http://xmlns.oracle.com/coherence/coherence-cache-config
                                  http://xmlns.oracle.com/coherence/coherence-cache-config/1.0/coherence-cache-config.xsd">

    <caching-scheme-mapping>
        <cache-mapping>
            <cache-name>myCache</cache-name>
            <scheme-name>distributed-scheme</scheme-name>
        </cache-mapping>
    </caching-scheme-mapping>

    <caching-schemes>
        <distributed-scheme>
            <service-name>DistributedCache</service-name>
            <backing-map-scheme>
                <local-scheme/>
            </backing-map-scheme>
        </distributed-scheme>
    </caching-schemes>

</cache-config>

1. Now, let’s create a Java class to interact with the Oracle Coherence cache. Here’s an example of how we can put and get data from the cache:

import com.tangosol.net.CacheFactory;
import com.tangosol.net.NamedCache;

public class CoherenceCacheExample {

    public static void main(String[] args) {
        CacheFactory.ensureCluster();
        NamedCache<String, String> cache = CacheFactory.getCache("myCache");

        cache.put("key", "value");

        String cachedValue = cache.get("key");
        System.out.println("Cached Value: " + cachedValue);

        CacheFactory.shutdown();
    }

}

Hazelcast

Hazelcast is an open-source, distributed, in-memory caching solution for Java applications. It provides a highly scalable and fault-tolerant caching infrastructure. Let’s see how we can implement distributed caching using Hazelcast in Java.

1. First, we need to include the Hazelcast dependency in our project. We can do this by adding the following Maven dependency to our pom.xml file:

<dependency>
    <groupId>com.hazelcast</groupId>
    <artifactId>hazelcast</artifactId>
    <version>X.X</version>
</dependency>

1. Next, let’s create a Hazelcast instance and configure the cache. Here’s an example:

import com.hazelcast.config.Config;
import com.hazelcast.core.Hazelcast;
import com.hazelcast.core.HazelcastInstance;
import com.hazelcast.core.IMap;

public class HazelcastCacheExample {

    public static void main(String[] args) {
        Config config = new Config();
        HazelcastInstance hazelcastInstance = Hazelcast.newHazelcastInstance(config);

        IMap<String, String> cache = hazelcastInstance.getMap("myCache");

        cache.put("key", "value");

        String cachedValue = cache.get("key");
        System.out.println("Cached Value: " + cachedValue);

        hazelcastInstance.shutdown();
    }

}

Conclusion

Distributed caching is a powerful technique that can significantly improve the performance and scalability of your Java applications. Oracle Coherence and Hazelcast are two popular caching frameworks that provide robust and efficient distributed caching capabilities. By implementing distributed caching with these frameworks, you can enhance your application’s responsiveness and ensure optimal data retrieval.

#distributedcaching #Java