Spring: Qualifier

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wx62e0d796b5814 2020-10-14 10:14:54 博主文章分类：SpringMVC ©著作权

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用于限定注入bean的特殊用法
1.定义注解

package tju.HclEurekaServer.anno;

import java.lang.annotation.Retention;
import java.lang.annotation.*;

import org.springframework.beans.factory.annotation.Qualifier;

@Retention(RetentionPolicy.RUNTIME)
@Qualifier
public @interface MyLoadBalanced {

}

2.配置bean

package tju.HclEurekaServer.controller;

import org.springframework.context.annotation.Bean;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import tju.HclEurekaServer.UserInfo;
import tju.HclEurekaServer.anno.MyLoadBalanced;

@RestController
public class MyController1 {
  
  @Bean
  //@MyLoadBalanced
  UserInfo getUserInfo()
  {
    UserInfo u=new UserInfo();
    u.setPassword("pwd");
    u.setUsername("yonghu");
    return u;
  }
  
  
  @Bean
  @MyLoadBalanced
  UserInfo getUserInfo2()
  {
    UserInfo u=new UserInfo();
    u.setPassword("amadeus");
    u.setUsername("liu");
    return u;
  }
  
  
  @Bean
  @MyLoadBalanced
  UserInfo getUserInfo3()
  {
    UserInfo u=new UserInfo();
    u.setPassword("david");
    u.setUsername("beckham");
    return u;
  }
  
  
  @Bean
  @MyLoadBalanced
  UserInfo getUserInfo4()
  {
    UserInfo u=new UserInfo();
    u.setPassword("ryn");
    u.setUsername("giggs");
    return u;
  }
  
  
  @Bean
  @MyLoadBalanced
  UserInfo getUserInfo5()
  {
    UserInfo u=new UserInfo();
    u.setPassword("crysti");
    u.setUsername("ronaldo");
    return u;
  }
  
  
  @RequestMapping("/hello")
  public String test()
  {
    return "hello,wd";
  }

}

注入 bean

package tju.HclEurekaServer.config;

import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

import tju.HclEurekaServer.UserInfo;
import tju.HclEurekaServer.anno.MyLoadBalanced;

@Configuration
public class MyConfig {
  
  @Autowired(required=false)
  @MyLoadBalanced
  private List<UserInfo> userInfoList=null;
  
  @Bean
  public String tt()
  {
    for(UserInfo u:userInfoList)
    {
      System.out.println(u);
    }
    return "good";
  }


}