Spring-通过注解注入Bean的几种方式(二)

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Component;

import java.util.List;
import java.util.Map;

/**
 * @Author: www.itze.cn
 * @Email: 814565718@qq.com
 */
@Component
public class MyBean {

    //List类型注入方式
    private List<String> list;

    public List<String> getList() {
        return list;
    }

    @Autowired
    @Qualifier(value = "testList")
    public void setList(List<String> list) {
        this.list = list;
    }

    //Map类型注入
    public Map<String,Integer> initMap;

    public Map<String, Integer> getInitMap() {
        return initMap;
    }
    @Autowired
    @Qualifier(value = "springMap")
    public void setInitMap(Map<String, Integer> initMap) {
        this.initMap = initMap;
    }

    //简单数据类型
    private String string;

    public String getString() {
        return string;
    }

    @Value("111")
    public void setString(String string) {
        this.string = string;
    }
}

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.core.annotation.Order;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

/**
 * @Author: www.itze.cn
 * @Email: 814565718@qq.com
 */
@Configuration
@ComponentScan(value = "com.example.demo")
public class BeanConfig {


    /**
     * 如果需要有List需要注入，Spring会有限考虑第二个String类型
     * 如果同时存在就是需要注入list需要添加BeanId
     *
     * @return
     */
    @Bean
    public List<String> testList() {
        List<String> list = new ArrayList<>();
        list.add("List");
        list.add("类型");
        return list;
    }

    @Bean("springMap")
    public Map<String, Integer> initMap() {
        Map<String, Integer> hashMap = new HashMap<>();
        hashMap.put("aaa", 123);
        hashMap.put("bbb", 456);
        hashMap.put("ccc", 777);
        return hashMap;
    }

    /**
     * @return
     * @Order注解类型int 不需要从下标0开始
     * 不需要连续
     * 值越小优先级越高
     */
    @Bean
    @Order(60)
    public String string1() {
        return "123";
    }

    @Bean
    @Order(50)
    public String string2() {
        return "456";
    }
    //Map类型使用
    @Bean
    public Integer integer1() {
        return 888;
    }

    @Bean
    public Integer integer2() {
        return 999;
    }
}

import com.example.demo.spring.BeanConfig;
import com.example.demo.spring.MyBean;
import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;

import java.util.List;
import java.util.Map;

/**
 * @Author: www.itze.cn
 * @Date: 2020/10/14 11:21
 * @Email: 814565718@qq.com
 */
public class Test {

    public static void main(String[] args) {
        //获取Spring上下文
        ApplicationContext applicationContext = new AnnotationConfigApplicationContext(BeanConfig.class);
        MyBean myBean = applicationContext.getBean("myBean", MyBean.class);
        System.out.println("myBean = " + myBean);
        //List类型
        for (String s : myBean.getList()) {
            System.out.println(s);
        }
        //Map类型
        for (Map.Entry<String, Integer> entry : myBean.getInitMap().entrySet()) {
            System.out.println(entry.getKey());
            System.out.println("value:" + entry.getValue());
        }
        //String类型
        System.out.println(myBean.getString());
        //内部接口
        List testList = myBean.getContext().getBean("testList", List.class);
        System.out.println("======================");
        for (Object o : testList) {
            System.out.println(o);
        }
        /**
         * 输出结果
         * myBean = com.example.demo.spring.MyBean@62da83ed
         * List
         * 类型
         * aaa
         * value:123
         * ccc
         * value:777
         * bbb
         * value:456
         * 111
         * ======================
         * List
         * 类型
         *
         */
    }
}