Spring Boot use component in a custom class? [closed]

I have a redis util :

@Component
public class RedisUtil {


    @Autowired
    private StringRedisTemplate stringRedisTemplate;


    public StringRedisTemplate getStringRedisTemplate() {
        return this.stringRedisTemplate;
    }
}

I want to use it in my custom class which I don't want to be a component .

public class UserFeature {
    
    public String result;

    public String someMethod(){
        var redisUtil = new RedisUtil();
        var stringRedisTemplate = redisUtil.getStringRedisTemplate();
        ...
        this.result = query_result_from_stringRedisTemplate;
    }
}

When I use it like above , it raises a bean error . What should I do ?

Solution 1:

If you have a good reason for creating objects which shouldn't be spring-managed, but still need to use spring beans, you can create a factory component which does the injection of spring beans into your non-spring object.

@Component
class UserFeatureFactory {
private final RedisUtil redisUtil;
  @Autowired
  public UserFeatureFactory(RedisUtil redisUtil) { ... }

  public UserFeature createUserFeature() {
    return new UserFeature(redisUtil);
  }
}

// no spring annotations
class UserFeature {
  ...
  public UserFeature(RedisUtil redisUtil) {
    this.redisUtil = redisUtil
  }
  ...
}

One nice feature of this approach is that it makes UserFeature easy to test -- you can just pass its constructor a mock RedisUtil.