spring 读取xml文件写法

beans.xml 文件

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
           http://www.springframework.org/schema/beans/spring-beans-2.5.xsd">

  <bean id="u" class="com.bjsxt.dao.impl.UserDAOImpl">
  </bean>
	
  <bean id="userService" class="com.bjsxt.service.UserService">
  	<!-- 
  	<property name="userDAO" ref="u" />
  	 -->
[b]　　　　<constructor-arg>
  	 	<ref bean="u"/>
  	 </constructor-arg>[/b]
  </bean>
  

</beans>

UserService 文件

package com.bjsxt.service;
import com.bjsxt.dao.UserDAO;
import com.bjsxt.model.User;



public class UserService {

	private UserDAO userDAO;
	public void add(User user) {
		userDAO.save(user);
	}
	public UserDAO getUserDAO() {
		return userDAO;
	}
	public void setUserDAO(UserDAO userDAO) {
		this.userDAO = userDAO;
	}
[color=red][b]
	public UserService(UserDAO userDAO) {
		super();
		this.userDAO = userDAO;
	}[/b][/color]
}

写法二：
beans 文件

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
           http://www.springframework.org/schema/beans/spring-beans-2.5.xsd">

  <bean id="u" class="com.bjsxt.dao.impl.UserDAOImpl">
  </bean>

[b]  <bean id="userService" class="com.bjsxt.service.UserService">
  <property name="userDAO" ref="u" />
 
  </bean>
 

</beans>[/b]

UserService 文件

package com.bjsxt.service;
import com.bjsxt.dao.UserDAO;
import com.bjsxt.model.User;



public class UserService {
private UserDAO userDAO; 
public void add(User user) {
userDAO.save(user);
}
public UserDAO getUserDAO() {
return userDAO;
}
public void setUserDAO(UserDAO userDAO) {
this.userDAO = userDAO;
}
　　　[b]　なし
}
[/b]