Spring中 idref标签和ref的区别

最新推荐文章于 2021-11-29 10:09:16 发布

原创最新推荐文章于 2021-11-29 10:09:16 发布 · 492 阅读

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本文详细介绍了 Spring 框架中 Bean 的两种注入方式：ref 和 idref 的区别，并通过具体的 Java 类和 XML 配置文件示例展示了这两种注入方式的应用场景及效果。

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首先先直白的解释，再详细介绍

区别:

ref:注入的是bean的实例
idref：注入的是string。

测试案例:

package com.pojo;

public class Card {
  private  String cno;
  private  String cpwd;
public String getCno() {
	return cno;
}
public void setCno(String cno) {
	this.cno = cno;
}
public String getCpwd() {
	return cpwd;
}
public void setCpwd(String cpwd) {
	this.cpwd = cpwd;
}
public Card(String cno, String cpwd) {
	super();
	this.cno = cno;
	this.cpwd = cpwd;
}
public Card() {
	super();
	// TODO Auto-generated constructor stub
}
 
}

第二个实体

package com.pojo;

import java.util.List;
import java.util.Set;

public class Person {
     
	
	 private  String name;
	 private String address;
	 private  String pid;
	 
	 private List<String> lStrings;
	 private Set<Card> sCards;
	 private Card card;
	 
	public Card getCard() {
		return card;
	}
	public void setCard(Card card) {
		this.card = card;
	}
	public Set<Card> getsCards() {
		return sCards;
	}
	public void setsCards(Set<Card> sCards) {
		this.sCards = sCards;
	}
	public List<String> getlStrings() {
		return lStrings;
	}
	public void setlStrings(List<String> lStrings) {
		this.lStrings = lStrings;
	}
	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
	public String getAddress() {
		return address;
	}
	public void setAddress(String address) {
		this.address = address;
	}
	public String getPid() {
		return pid;
	}
	public void setPid(String pid) {
		this.pid = pid;
	}
	@Override
	public String toString() {
		return "Person [name=" + name + ", address=" + address + ", pid=" + pid + "]";
	}
	 
	public void initPerson() {
		System.out.println("初始化的方法"); 
	}
}

配置文件：

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
   xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
   xmlns:aop="http://www.springframework.org/schema/aop"
   xmlns:util="http://www.springframework.org/schema/util"
   xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.3.xsd
       http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-4.3.xsd
       http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-4.3.xsd">

<bean id="person1" class="com.pojo.Person" scope="prototype" init-method="initPerson">

</property>

<property name="card" ref="card"></property>

<property name="card" >
<idref bean="c"/>
</property>

</bean>

</beans>

最后是temp:

用的Junit

package com.temp;

import org.junit.Test;
import org.springframework.beans.factory.BeanFactory;
import org.springframework.beans.factory.xml.XmlBeanFactory;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import org.springframework.core.io.ClassPathResource;

import com.zking.pojo.Card;
import com.zking.pojo.Person;

public class SpringTemp {

	
	@Test
	  public  void  createBean() {
		 
		ApplicationContext applicationContext=new ClassPathXmlApplicationContext("applicationContext.xml");
		
		Person person=(Person)	applicationContext.getBean("person1");
 
		
		System.out.println(person.getCard().getCno()+".........."+person.getCard().getCpwd());
		
		
		
	}
}

测试结果：

<property name="card">中设置了<idref bean="c"/> 而card这个bean在当前的容器中并不存在所以出错。

将<idref bean="card"/> 改为<idref bean="card"/>顺利运行.