Redis client for Java: Jedis, Lettuce, Redisson

Redis client for Java: overview of popular libraries

Redis is a high-performance key-value data store, widely used for caching, sessions, queues, and real-time analytics. There are several mature client libraries for working with Redis from Java. In this article, we will look at three of the most popular ones: Jedis, Lettuce and Redisson. Each of them has its own features, advantages, and use cases.

1. Jedis — simple and lightweight client

Jedis is a minimalist synchronous client for Redis. It is easy to learn and well-suited for small projects and microservices where asynchronicity is not required.

Features of Jedis:

Synchronous API (blocking calls).
Connection pool support (JedisPool).
Full support for Redis commands.
Does not support asynchronous or reactive operations.

Example of connection and basic operations:

import redis.clients.jedis.Jedis;import redis.clients.jedis.JedisPool;

public class JedisExample {    public static void main(String[] args) {        // Create a connection pool        try (JedisPool pool = new JedisPool("localhost", 6379);             Jedis jedis = pool.getResource()) {

            // Set and get a value            jedis.set("user:100", "Alice");            String value = jedis.get("user:100");            System.out.println("Value: " + value); // Output: Alice

            // Working with lists            jedis.lpush("queue", "task1");            jedis.lpush("queue", "task2");            String task = jedis.rpop("queue");            System.out.println("Task from queue: " + task); // Output: task1        }    }}

When to choose Jedis:

Simple project without reactive requirements.
Need a minimal dependency (single jar).
Classic blocking operations.

2. Lettuce — asynchronous and reactive client

Lettuce is a modern client built on Netty. It supports synchronous, asynchronous, and reactive (Reactive Streams) APIs. It is an excellent choice for high-load systems.

Features of Lettuce:

Asynchronous and reactive API (based on Project Reactor).
Support for Redis clusters, Sentinel, SSL.
Non-blocking operations — high throughput.
Support for Redis Pub/Sub, Streams, Transactions.

Example of asynchronous usage:

import io.lettuce.core.RedisClient;import io.lettuce.core.api.StatefulRedisConnection;import io.lettuce.core.api.async.RedisAsyncCommands;

public class LettuceAsyncExample {    public static void main(String[] args) {        RedisClient client = RedisClient.create("redis://localhost:6379");        try (StatefulRedisConnection<String, String> connection = client.connect()) {            RedisAsyncCommands<String, String> async = connection.async();

            // Asynchronous set            async.set("key:1", "Hello, Lettuce!");

            // Asynchronous get with callback            async.get("key:1").thenAccept(value ->                 System.out.println("Received: " + value)            );

            // Small delay to complete the asynchronous operation            try { Thread.sleep(100); } catch (InterruptedException e) { }        }        client.shutdown();    }}