Setter注入和依赖对象示例

就像构造函数注入一样，我们可以使用setter注入另一个bean的依赖项。在这种情况下，我们使用 property 元素。在这里，我们的场景是 Employee HAS-A Address。 Address类对象将称为从属对象。首先让我们看一下Address类:

Address.java

该类包含四个属性，即setter和getter以及toString()方法。

示例

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

它包含三个属性id，名称和地址(依赖对象)，使用displayInfo()方法的setter和getter。

示例

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

属性元素的 ref 属性用于定义另一个bean的引用。

示例

<?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

此类从applicationContext.xml文件获取Bean并调用displayInfo()方法。

示例

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();
    
}
}

Setter注入和集合示例 Spring setter方法注入

Setter注入和依赖对象示例

Spring 教程