Master Redis in Spring Boot: From RedisTemplate to Redisson Integration

In modern application development Redis is a crucial speed‑up component for caching, ranking, session storage, message queues, rate limiting and more.

Dependency Introduction

The core dependency is spring-boot-starter-data-redis, which enables immediate use of RedisTemplate after inclusion.

<dependency>
  <groupId>org.springframework.boot</groupId>
  <artifactId>spring-boot-starter-data-redis</artifactId>
  <version>2.5.14</version>
</dependency>

Principle Analysis

RedisTemplate

comes from the spring-data-redis library. It operates on a RedisConnectionFactory which supplies the actual RedisConnection similar to how JDBC provides a Connection for SQL.

public interface RedisConnectionFactory extends PersistenceExceptionTranslator {
  RedisConnection getConnection();
  RedisClusterConnection getClusterConnection();
  boolean getConvertPipelineAndTxResults();
  RedisSentinelConnection getSentinelConnection();
}

The two main implementations are JedisConnectionFactory and LettuceConnectionFactory; Spring Boot defaults to Lettuce because of its superior performance.

How to Configure the Connection

Customizing RedisConnectionFactory and RedisTemplate parameters can be done via a @Bean method:

@Bean("stringObjectRedisTemplate")
public RedisTemplate<String, Object> stringObjectRedisTemplate(RedisConnectionFactory factory) {
  RedisTemplate<String, Object> redisTemplate = new RedisTemplate<>();
  redisTemplate.setConnectionFactory(factory);
  redisTemplate.setKeySerializer(RedisSerializer.string());
  redisTemplate.setHashKeySerializer(RedisSerializer.string());
  redisTemplate.setValueSerializer(RedisSerializer.json());
  redisTemplate.setHashValueSerializer(RedisSerializer.json());
  return redisTemplate;
}

1. Single‑Node Mode

spring:
  application:
    name: myapplication
  redis:
    host: 127.0.0.1
    port: 6379
    database: 0
    password: 123456
    lettuce:
      pool:
        min-idle: 2
        max-idle: 4
        max-active: 10
        max-wait: -1
        time-between-eviction-runs: 1

2. Sentinel (Cluster) Mode

spring:
  redis:
    sentinel:
      master: mymaster
      nodes:
        - 192.168.1.101:26379
        - 192.168.1.102:26379
        - 192.168.1.103:26379
      password: yourpassword
      database: 0

Integrating Redisson Client

Redisson provides a richer API that resembles Java collections, useful for distributed locks, Bloom filters, maps, etc. Add the starter dependency:

<dependency>
  <groupId>org.redisson</groupId>
  <artifactId>redisson-spring-boot-starter</artifactId>
  <version>3.38.1</version>
</dependency>

Configure a RedissonClient bean:

@Bean
public RedissonClient redissonClient() {
  Config config = new Config();
  config.useSingleServer().setAddress("redis://" + host + ":" + port).setPassword(password);
  return Redisson.create(config);
}

Optionally expose a RedissonConnectionFactory for Spring Data Redis compatibility:

@Bean
public RedissonConnectionFactory redissonConnectionFactory(RedissonClient client) {
  return new RedissonConnectionFactory(client);
}

Version Compatibility

Spring Boot 2.x works well with redisson-spring-boot-starter 3.x. For Spring Data Redis 2.5.x, use redisson-spring-data-25 to avoid conflicts.

Utility Wrapper

To make Redis usage truly plug‑and‑play, a utility class can encapsulate common commands for strings, hashes, lists, sorted sets, bitmaps, and Lua scripts.

By combining RedisTemplate for simple key‑value operations and RedissonClient for advanced distributed structures, developers gain a flexible and powerful Redis integration in Spring Boot.