1.用构造器来实例化

 



print?
1. <bean id="hello2" class="com.hsit.hello.impl.ENhello" />

 

2.使用静态工厂方法实例化

 

要写一个bean，bean中定义一个静态方法，生成bean，配置factory-method指定静态方法，运行时容器就会自动调用静态方法生成实例

 

bean

 


 

1. package com.hsit.hello.impl;  
2.   
3. import com.hsit.hello.IHello;  
4.   
5. public class CHhello implements IHello {  
6.   
7. private String msg;  
8.   
9. public void sayHello() {  
10. "中文" + msg);  
11.     }  
12.   
13. public String getMsg() {  
14. return msg;  
15.     }  
16.   
17. public void setMsg(String msg) {  
18. this.msg = msg;  
19.     }  
20.       
21. @Override  
22. public String toString() {  
23. // TODO Auto-generated method stub  
24. return "Chinese";  
25.     }  
26.   
27. public static CHhello createInstance() {  
28. "jingtai");  
29. return new CHhello();  
30.     }  
31. }

 

配置文件

 

1. <bean id="hello1" class="com.hsit.hello.impl.CHhello" factory-method="createInstance" lazy-init="true">  
2. <!-- setter注入 -->  
3. <property name="msg" value="哈哈">  
4. </property>  
5. </bean>


 

3.使用实例工厂方法实例化

 

 

要写两个bean，一个是要实例化的bean，另一个是工厂bean。容器先实例化工厂bean，然后调用工厂bean配置项factory-method中指定的静态方法，在方法中实例化bean



1. package com.hsit.hello.impl;  
2.   
3. public class ENhelloFactory {  
4.       
5. public ENhello createInstance() {  
6. "ENhello工厂");  
7. return new ENhello();  
8.     }  
9.       
10. public ENhelloFactory() {  
11. "chuanjian");  
12.     }  
13.   
14. }

 



1. package com.hsit.hello.impl;  
2.   
3. import com.hsit.hello.IHello;  
4.   
5. public class ENhello implements IHello {  
6.   
7. @Override  
8. public void sayHello() {  
9. // TODO Auto-generated method stub  
10. "hello");  
11.     }  
12.       
13. @Override  
14. public String toString() {  
15. // TODO Auto-generated method stub  
16. return "我是ENhello";  
17.     }  
18. }

配置文件


1. <bean id="eHelloFactory" class="com.hsit.hello.impl.ENhelloFactory" />  
2. <!-- factory-bean填上工厂bean的id，指定工厂bean的工厂方法生成实例，class属性不填 -->  
3. <bean id="example" factory-bean="eHelloFactory"   factory-method="createInstance"/>

 

测试代码

1. BeanFactory factory = new ClassPathXmlApplicationContext("applicationContext.xml");  
2.           
3. "example");  
4.         System.out.println(eNhello.toString());  
5.           
6. "hello1");