<!--1.无参构造-->
<!--单例模式，默认的设置，在加载容器之前bean中的对象就会被创建-->
<bean id="user1",class="XXX.User" scope="singleton">
<!--多例模式，在加载容器之后，bean中的对象才会被创建,不管是否调用applictionContext.getBean()-->
<bean id="user2",class="XXX.User" scope="prototype">
<!--多例模式延迟加载，在调用applictionContext.getBean()之后，对象才会被创建-->
<bean id="user3",class="XXX.User" scope="prototype" lazy-init="true">

class User{
    private int id;
    private String name;
    public User(){
    }
    public User(int id,String name){
    this.id=id;
    this.name=name;
    }
  public void initUser(){
  System.out.println("初始化");
  }  
  public void destroyUser(){
  System.out.println("对象销毁");
  }  

//get and set

//toString()
}

class UserFactory{
    public User getInstance(){
        return new User();
    }

    public static User getStaticInstance(){
        return new User();
    }
}

<!--1.无参构造-->
<!--单例模式，默认的设置，在加载容器之前bean中的对象就会被创建-->
<bean id="user1",class="XXX.User" scope="singleton">
<!--多例模式，在加载容器之后，bean中的对象才会被创建,不管是否调用applictionContext.getBean()-->
<bean id="user2",class="XXX.User" scope="prototype">
<!--多例模式延迟加载，在调用applictionContext.getBean()之后，对象才会被创建-->
<bean id="user3",class="XXX.User" scope="prototype" lazy-init="true">

<!--2.参数构造-->
<bean id="str" calss="java.lang.String">
    <constructor-arg   value="Tom" ></constructor-arg>
</bean>
<bean id="user4" calss="java.lang.String">
    <constructor-arg index="0" value="998" type="int"></constructor-arg>
    <constructor-arg index="1" ref="s"></constructor-arg>
</bean>


<!--3.工厂模式创建对象 -->
<!--工厂模式创建对象，使用非静态方法-->
<bean id="factory",class="XXX.UserFactory" >
<bean id="user5"，factory-bean="factory" factory-method="getInstance">

<!--工厂模式创建对象，使用静态方法-->
<bean id="user6"，calss="XXX.UserFactory" factory-method="getStaticInstance">

<!--1.参数构造-->
<bean id="user1" calss="xxx.User">
    <constructor-arg index="0" value="998" type="int"></constructor-arg>
    <constructor-arg index="1" value="Tom" type="java.lang.String"></constructor-arg>
</bean>

<bean id="str" calss="java.lang.String">
    <constructor-arg   value="Tom" ></constructor-arg>
</bean>
<bean id="user2" calss="xxx.User">
    <constructor-arg index="0" value="998" type="int"></constructor-arg>
    <constructor-arg index="1" ref="s"></constructor-arg>
</bean>

<!--2.通过set方法对属性注入-->
<bean id="user3" calss="xxx.User">
    <property name="id" value="998"></property>
    <property name="name" value="Tom "></property>
</bean>

class Test{
    
    public static void main(String[] args){
        ApplicationContext applicationContext=new ClassPathXmlApplicationContext("applicationContext.xml");//注意文件的路径
        UserAction userAction=(UserAction) applicationContext.getBean("userAction");
        userAction.adddUser();
    }
}

//UserController.java
class UserController{

    UserService userService;

    private void setUserService(UserService userService){
        this.userService=userService;
    }

    private void addUser(){
        userService.save();
    }
}

//UserService.java
class UserService {

    private UserDao userDao;

    private void setUserDao (UserDao userDao){
        this.userDao=userDao;
    }

    private void save(){
        userDao.save();
    }
}

//UserDao .java
class UserDao {

    public void save(){
       System.out.println("正在保存");
    }
}

注入controller、service、dao方式1

applicationContext.xml文件 

<!--  Controller -->
<bean id="userController" calss="xxx.UserController">
    <property name="userService" ref="userService"></property>
</bean>

<!--  Service -->
<bean id="userService " calss="xxx.UserService r">
    <property name="userDao" ref="userDao"></property>
</bean>

<!--  Dao -->
<bean id="userDao" calss="xxx.UserDao">
</bean>

注入controller、service、dao方式2
applicationContext.xml文件 

<!--  Controller -->
<bean id="userController2" calss="xxx.UserController">
    <property name="userService" >
        <bean calss="xxx.UserService></bean>
            <property name="userDao" >
                <bean calss="xxx.UserDao></bean>
            </property>
    </property>
</bean>