spring依赖的几种注入方式

spring不推荐使用@Autowired注解进行注入，推荐使用后面两种方式进行注入，具体还是各位看自己平时的使用习惯，或者是否有要求：

1.@Autowired

public class UserController {
  @Autowired
  private UserService userService;      
}

 

2.@Resource

public class UserController {
  @Resource
  private UserService userService;      
}

 

3.使用setter注入

public class UserController {
  private UserService userService;
  
  public void setter(UserService userService){
       this.userService = userService;      
  }          
}    

 

4.使用构造注入

public class UserController {
 
  private UserService userService;    

  public UserController(UserService userService){
        this.userService = userService;
  }  
}