後端-框架-Spring-IoC-contructor-arg

public class UserServiceImpl implements UserService {

	// 宣告介面型別的引用，和具體實現類解耦合
	private UserDao dao;
	private String s1;
	private String s2;
	private int i1;

	public UserServiceImpl() {

	}
	
	public UserServiceImpl(UserDao dao) {
		this.dao = dao;
	}

	public UserServiceImpl
 
(UserDao dao, String s1) {
		this.dao = dao;
		this.s1 = s1;
	}
	
	public UserServiceImpl(UserDao dao, int i1) {
		this.dao = dao;
		this.i1 = i1;
	}

	public UserServiceImpl(String s2, UserDao dao) {
		this.s2 = s2;
		this.dao = dao;

	}
}

<bean id="UserService" class="cn.service.UserServiceImpl"
 
>
		<constructor-arg>
			<ref bean="UserDao"/>
		</constructor-arg>
		<!-- index為構造方法中第幾個引數,Re:0 -->
		<!-- type為構造方法的引數型別 -->
		<constructor-arg index="1" type="int">
			<value>123</value>
		</constructor-arg>
</bean>