bean的装配方式（注入方式，构造注入，setter属性注入）

bean的装配方式有两种，构造注入和setter属性注入。

public class User {
    private  String username;
    private String password;
    private List<String> list;
//构造注入需要提供带所有参数的有参构造方法
    public User(String username, String password, List<String> list) {
        this.username = username;
        this.password = password;
        this.list = list;
    }
//设置注入，需要提供无参构造方法和setter和getter方法
    public User() {
    }

    public String getUsername() {
        return username;
    }
    public void setUsername(String username) {
        this.username = username;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }

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

    public void setList(List<String> list) {
        this.list = list;
    }

    @Override
    public String toString() {
        return "User{" +
                "username='" + username + '\'' +
                ", password='" + password + '\'' +
                ", list=" + list +
                '}';
    }
}

在applicationContext.xml中的配置

<!--构造方法方式装配bean-->
<!--在这儿可以采用p名称空间的形式注入值-->
    <bean id="user1" class="com.itheima.ioc.xmlzhuangpeiBean.User">
        <constructor-arg index="0" value="chen"/>
        <constructor-arg index="1" value="123456"/>
        <constructor-arg index="2">
            <list>
                <value>"user1"</value>
                <value>"user2"</value>
            </list>
        </constructor-arg>
    </bean>
    <!--使用设置注入方式装配bean-->

<!--在这儿可以采用p名称空间的形式注入值-->

    <bean id="user2" class="com.itheima.ioc.xmlzhuangpeiBean.User">
        <property name="username" value="陈红君"/>
        <property name="password" value="145678"/>
        <property name="list">
            <list>
                <value>"4679"</value>
                <value>"213"</value>
            </list>
        </property>
    </bean>
<!--例如这儿的bean可以写成这样
<bean id="user2" class="类的全限定名" p:username="小城" p:password="123"/>
-->

</beans>

基于注解的装配
接口UserDao

public interface UserDao {
    public void userDaoSay();

}
实现接口的USerDaoImp

@Repository("userDao")//用于数据访问层
public class UserDaoImp implements UserDao {
    @Override
    public void userDaoSay() {
        System.out.println("这是实现userdao的方法");
    }
}

接口UserService 

public interface UserService {
    public  void  userServiceSay();
}
实现接口的UserServiceImp

@Service("userService")
public class UserServiceImp implements UserService {
    @Resource(name = "userDao")//按照实例名称进行装配的
    private UserDao userDao;

    public void userServiceSay() {
        this.userDao.userDaoSay();
        System.out.println("userservice to say hello world!");

    }
}
控制器UserController 

@Controller("userController")//控制器
public class UserController {
    @Resource(name = "userService")
    private UserService userService;

    public void userControllerSay() {
        this.userService.userServiceSay();
        System.out.println("userController to Say hello world!");
    }

/*实例化一个userController对象，调用userControllerSay()方法，userController 先调用userService里的方法
当执行到了userService，userService就去调用执行userDao中的userDaoSay（）方法
* */
}
applicationContext.xml中的配置

<?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-3.0.xsd">
    
    <context:component-scan base-package="com.itheima.ioc.zhujiefangshizhuangpeiBean"/>

</beans>

测试

public class annotationTest {
    public static void main(String[] args) {
        ApplicationContext applicationContext = new ClassPathXmlApplicationContext("anntationContext.xml");
        UserController userController = (UserController) applicationContext.getBean("userController");
        userController.userControllerSay();
    }
}