就像構(gòu)造函數(shù)注入一樣，我們可以使用setter注入另一個bean的依賴項(xiàng)。在這種情況下，我們使用
property 元素。在這里，我們的場景是
Employee HAS-A Address。 Address類對象將稱為從屬對象。首先讓我們看一下Address類:
Address.java
該類包含四個屬性，即setter和getter以及toString()方法。
package com.nhooo;
public class Address {
private String addressLine1,city,state,country;
//getters and setters
public String toString(){
return addressLine1+" "+city+" "+state+" "+country;
}
Employee.java
它包含三個屬性id，名稱和地址(依賴對象)，使用displayInfo()方法的setter和getter。
package com.nhooo;
public class Employee {
private int id;
private String name;
private Address address;
//setters and getters
void displayInfo(){
System.out.println(id+" "+name);
System.out.println(address);
}
}
applicationContext.xml
屬性元素的
ref 屬性用于定義另一個bean的引用。
<?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:p="http://www.springframework.org/schema/p"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.0.xsd">
<bean id="address1" class="com.nhooo.Address">
<property name="addressLine1" value="51,Lohianagar"></property>
<property name="city" value="Ghaziabad"></property>
<property name="state" value="UP"></property>
<property name="country" value="India"></property>
</bean>
<bean id="obj" class="com.nhooo.Employee">
<property name="id" value="1"></property>
<property name="name" value="Sachin Yadav"></property>
<property name="address" ref="address1"></property>
</bean>
</beans>
Test.java
此類從applicationContext.xml文件獲取Bean并調(diào)用displayInfo()方法。
package com.nhooo;
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 org.springframework.core.io.Resource;
public class Test {
public static void main(String[] args) {
Resource r=new ClassPathResource("applicationContext.xml");
BeanFactory factory=new XmlBeanFactory(r);
Employee e=(Employee)factory.getBean("obj");
e.displayInfo();
}
}