springboot 从redis中取出json数据，请写出代码

在Spring Boot中，要从Redis获取JSON数据，你可以使用Spring Data Redis的`ValueOperations`接口。以下是一个简单的示例，展示如何使用JedisTemplate或 lettuce等Redis客户端操作工具：

**使用JedisTemplate:**

import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.data.redis.core.ValueOperations;

public class RedisService {

    private final StringRedisTemplate stringRedisTemplate;

    public RedisService(StringRedisTemplate stringRedisTemplate) {
        this.stringRedisTemplate = stringRedisTemplate;
    }

    public Object getJsonFromRedis(String key) {
        ValueOperations<String, String> operations = stringRedisTemplate.opsForValue();
        String jsonContent = operations.get(key);
        return jsonContent == null ? null : new ObjectMapper().readValue(jsonContent, YourObject.class); // 假设YourObject是你的JSON模型类
    }
}

**使用lettuce:**

import io.lettuce.core.api.StatefulRedisConnection;
import io.lettuce.core.api.async.RedisFuture;
import io.lettuce.core.json.JsonMapper;

public class RedisService {

    private final LettuceConnectionFactory connectionFactory;

    public RedisService(LettuceConnectionFactory connectionFactory) {
        this.connectionFactory = connectionFactory;
    }

    public CompletableFuture<YourObject> getJsonFromRedis(String key) throws Exception {
        StatefulRedisConnection<String, String> redis = connectionFactory.connect();
        try {
            String jsonContent = redis.get(key).get();
            return CompletableFuture.completedFuture(JsonMapper.jsonObjectMapper().fromJson(jsonContent, YourObject.class));
        } finally {
            redis.close();
        }
    }
}

注意这里假设你已经有了一个`YourObject`类，这个类需要有对应的Jackson或Gson的反序列化方法来解析JSON字符串。