从头认识Spring-1.9 内部类注入Bean

Posted 2020-09-26 wzzkaifa

这一章节我们来讨论一下内部类注入Bean。

1.domain

蛋糕类：（跟前一章节的一样）

package com.raylee.my_new_spring.my_new_spring.ch01.topic_1_9;

public class Cake {

	private final int id = index++;

	private static int index = 0;

	private String name = "";

	private double size = 0;

	public String getName() {
		return name;
	}

	public void setName(String name) {
		this.name = name;
	}

	public double getSize() {
		return size;
	}

	public void setSize(double size) {
		this.size = size;
	}

	public int getId() {
		return id;
	}

	@Override
	public String toString() {
		return "create the cake,its id:" + id + ", size:" + size + " inch ,name:" + name;
	}
}

厨师类：（基本没有变化）

package com.raylee.my_new_spring.my_new_spring.ch01.topic_1_9;

public class Chief {

	private Cake cake = null;

	public Cake getCake() {
		return cake;
	}

	private String name = "";

	public Chief(String name) {
		this.name = name;
	}

	public Chief(String name, Cake cake) {
		this.name = name;
		this.cake = cake;
	}

	public String getName() {
		return name;
	}

	public void setName(String name) {
		this.name = name;
	}

	public void setCake(Cake cake) {
		this.cake = cake;
	}

	private final int id = index++;

	public int getId() {
		return id;
	}

	private static int index = 0;

	public Cake makeOneCake() {
		return cake;
	}

}

 

 

測试类：

package com.raylee.my_new_spring.my_new_spring.ch01.topic_1_9;

import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.ApplicationContext;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(locations = {
		"/com/raylee/my_new_spring/my_new_spring/ch01/topic_1_9/ApplicationContext-test.xml" })
public class ChiefTest {

	@Autowired
	private ApplicationContext applicationContext;

	@Test
	public void testChief() {
		Chief chief = applicationContext.getBean(Chief.class);
		System.out.println("chief name:" + chief.getName());
		System.out.println(chief.getName() + " make a cake ,cake‘s name :" + chief.makeOneCake());
	}
}

2.配置文件

以下是通过属性注入内部类的配置文件

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
	xmlns:context="http://www.springframework.org/schema/context"
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:tx="http://www.springframework.org/schema/tx"
	xmlns:aop="http://www.springframework.org/schema/aop"
	xsi:schemaLocation="
        http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.1.xsd
		http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.1.xsd
		http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.1.xsd
		http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-3.1.xsd
		http://www.springframework.org/schema/data/jpa http://www.springframework.org/schema/data/jpa/spring-jpa-1.0.xsd
		http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
       http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd">

	<bean id="chief"
		class="com.raylee.my_new_spring.my_new_spring.ch01.topic_1_9.Chief">
		<constructor-arg value="jack" />
		<property name="cake">
			<bean class="com.raylee.my_new_spring.my_new_spring.ch01.topic_1_9.Cake">
				<property name="name" value="jack‘s own cake" />
				<property name="size" value="9" />
			</bean>
		</property>
	</bean>
</beans>

注意：我们内部类注入，配置文件中面的cake是不带id的，并且。他不能为其它的Bean所公用。

 

以下是通过构造器注入内部类的配置文件：

<?
xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
	xmlns:context="http://www.springframework.org/schema/context"
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:tx="http://www.springframework.org/schema/tx"
	xmlns:aop="http://www.springframework.org/schema/aop"
	xsi:schemaLocation="
        http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.1.xsd
		http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.1.xsd
		http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.1.xsd
		http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-3.1.xsd
		http://www.springframework.org/schema/data/jpa http://www.springframework.org/schema/data/jpa/spring-jpa-1.0.xsd
		http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
       http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd">

	<bean id="chief"
		class="com.raylee.my_new_spring.my_new_spring.ch01.topic_1_9.Chief">
		<constructor-arg value="jack" />
		<constructor-arg>
			<bean class="com.raylee.my_new_spring.my_new_spring.ch01.topic_1_9.Cake">
				<property name="name" value="jack‘s own cake" />
				<property name="size" value="9" />
			</bean>
		</constructor-arg>
	</bean>
</beans>

大家须要注意的是。我们上面的配置文件配置Bean的时候配置了两个属性，因此我们的构造器里面，必须存在这两个属性值，不然就会抛异常。

 

总结：这一章节主要介绍内部类注入Bean的形式和注意点。

 

文件夹：http://blog.csdn.net/raylee2007/article/details/50611627 

 

我的github：https://github.com/raylee2015/my_new_spring