Spring基于注解的DI-基本注解

简单的创建一个Java 工程，配置好环境

Strudent.java

package com.hk.spring.di01;

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

//与@Component功能相同但是意义不同的注解还有三个
//1、@Controller     （注解在处理器上【SpringMvc】）
//2、@Repository     （注解在Dao实现类上）
//3、@Service        （注解在Service实现类上）
@Component("myStudent")
public class Student {
          
   
    @Value("小明")
    private String name;
    @Value("23")
    private int age;
    @Autowired      //域属性的byType自动注入
    private School school;//域属性
    public void setName(String name) {
        this.name = name;
    }
    public void setAge(int age) {
        this.age = age;
    }

    public void setSchool(School school) {
        this.school = school;
    }
    @Override
    public String toString() {
        return "Student [name=" + name + ", age=" + age + ", school=" + school
                + "]";
    }


}

域属性的byName自动注入 域属性的byType自动注入的另一种形式

//import javax.annotation.Resource;是Java的标准注入
    @Resource//域属性的byType自动注入
    private School school;//域属性

域属性的byName自动注入的另一种形式

//import javax.annotation.Resource;
    @Resource(name="mySchool")//域属性的byName自动注入
    private School school;//域属性

School.java

package com.hk.spring.di01;

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


@Component("mySchool")//组件
public class School {
          
   
    @Value("九江学院")
    private String schloolName;

    public void setSchloolName(String schloolName) {
        this.schloolName = schloolName;
    }

    @Override
    public String toString() {
        return "School [schloolName=" + schloolName + "]";
    }

}

applicationContext.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns:context="http://www.springframework.org/schema/context" xsi:schemaLocation="
        http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/context
        http://www.springframework.org/schema/context/spring-context.xsd">
        <!-- 配置组件扫描器    就是说明你的bean注解在哪个包下 -->
         <context:component-scan base-package="com.hk.spring.di01"></context:component-scan>
</beans>

Mytest.java

package com.hk.spring.di01;

import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

public class Mytest {
    @Test
    public void test1(){
        String resource = "com/hk/spring/di01/applicationContext.xml";
        ApplicationContext ac = new ClassPathXmlApplicationContext(resource);
        Student stu = (Student) ac.getBean("myStudent");
        System.out.println(stu);

    }
}