Spring的配置：屬性注入

Car.java

package com.cherry.spring.demo4;

public class Car {
	private String name;
	private Double price;
	public Car(String name, Double price) {
		super();
		this.name = name;
		this.price = price;
	}
	@Override
	public String toString() {
		return "Car [name=" + name + ", price=" + price + "]";
	}
	
	
}

Car2.java

package com.cherry.spring.demo4;
/**
 * set方法的屬性注入
 * @author zhang
 *
 */
public class Car2 {
	private String name;
	private Double price;
	public void setName(String name) {
		this.name = name;
	}
	public void setPrice(Double price) {
		this.price = price;
	}
	@Override
	public String toString() {
		return "Car2 [name=" + name + ", price=" + price + "]";
	}
	
	
}

Employee.java

package com.cherry.spring.demo4;

public class Employee {
	private String name;
	private Car2 car2;
	public void setName(String name) {
		this.name = name;
	}
	public void setCar2(Car2 car2) {
		this.car2 = car2;
	}
	@Override
	public String toString() {
		return "Employee [name=" + name + ", car2=" + car2 + "]";
	}
	
	
}

applicationContext.xml

<?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.xsd">
	
	
	<!-- Spring的屬性注入的方式 -->
	<!-- 構造方法的方式 -->
	<bean id="car" class="com.cherry.spring.demo4.Car">
		<constructor-arg name="name" value="捷達"/>
		<constructor-arg name="price" value="50000"/>
	</bean>
	
	<!-- set方法的方式 -->
	<bean id="car2" class="com.cherry.spring.demo4.Car2">
		<property name="name" value="桑塔納"/>
		<property name="price" value="20000"/>
	</bean>
	
	<!-- set方法注入對象類型的屬性 -->
	<bean id="employee" class="com.cherry.spring.demo4.Employee">
		<!-- value:設置普通類型的值，ref：設置其他的類的id或name -->
		<property name="name" value="lion"/>
		<property name="car2" ref="car2"/>
	</bean>

    <!-- 改爲p名稱空間的方式 -->
	<!-- <bean id="car2" class="com.cherry.spring.demo4.Car2" p:name="奇瑞" p:price="30000"></bean>
	
	<bean id="employee" class="com.cherry.spring.demo4.Employee" p:name="liu" p:car2-ref="car2"></bean> -->
	
	<!-- SpEL的屬性注入 -->
	<bean id="carInfo" class="com.cherry.spring.demo4.CarInfo">
	</bean>
	
	<bean id="car2" class="com.cherry.spring.demo4.Car2">
		<property name="name" value="#{carInfo.name}"></property>
		<property name="price" value="#{carInfo.calculatorPrice()}"></property>
	</bean>
	
	<bean id="employee" class="com.cherry.spring.demo4.Employee">
		<property name="name" value="#{'feng'}"></property>
		<property name="car2" value="#{car2}"></property>
	</bean>

    <!-- Spring的集合屬性的注入:類中需要提供set方法 -->
	<!-- 注入數組類型 -->
	<bean id="collection" class="com.cherry.spring.demo5.CollectionBean">
		<!-- 數組類型 -->
		<property name="args">
			<list>
				<value></value>
				<ref/>
			</list>
		</property>
		
		<!-- 注入list集合 -->
		<property name="list">
			<list>
				<value></value>
				<value></value>
			</list>
		</property>
		
		<!-- 注入set集合 -->
		<property name="set">
			<set>
				<value></value>
			</set>
		</property>
		
		<!-- 注入map集合 -->
		<property name="map">
			<map>
				<entry key="" value=""/>
			</map>
		</property>
	</bean>

</beans>

測試類

package com.cherry.spring.demo4;

import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

/**
 * 屬性注入的方式
 * @author zhang
 *
 */
public class SpringDemo4 {
	
	@Test
	/**
	 * 構造方法的注入
	 */
	public void demo1() {
		ApplicationContext applicationContext=new ClassPathXmlApplicationContext("applicationContext.xml");
		Car car = (Car) applicationContext.getBean("car");
		System.out.println(car);
	}
	
	@Test
	/**
	 * set方法的注入
	 */
	public void demo2() {
		ApplicationContext applicationContext=new ClassPathXmlApplicationContext("applicationContext.xml");
		Car2 car2 = (Car2) applicationContext.getBean("car2");
		System.out.println(car2);
	}
	
	@Test
	/**
	 * set方法注入對象類型
	 */
	public void demo3() {
		ApplicationContext applicationContext=new ClassPathXmlApplicationContext("applicationContext.xml");
		Employee employee = (Employee) applicationContext.getBean("employee");
		System.out.println(employee);
	}
}

通過修改配置文件，從而避免頻繁修改源代碼