package com.yiibai.common;

public class Customer 
{
	private Person person;

	public Customer(Person person) {
		this.person = person;
	}

	public void setPerson(Person person) {
		this.person = person;
	}

	@Override
	public String toString() {
		return "Customer [person=" + person + "]";
	}
}

package com.yiibai.common;

public class Person 
{
	private String name;
	private String address;
	private int age;
	
	//getter and setter methods
	
	@Override
	public String toString() {
		return "Person [address=" + address + ", 
                               age=" + age + ", name=" + name + "]";
	}	
}

很多時(shí)候，可以使用 'ref' 屬性來(lái)引用“Person” bean到“Customer” Bean，person的屬性如下：

<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-2.5.xsd">

	<bean id="CustomerBean" class="com.yiibai.common.Customer">
		<property name="person" ref="PersonBean" />
	</bean>

	<bean id="PersonBean" class="com.yiibai.common.Person">
		<property name="name" value="yiibai" />
		<property name="address" value="address1" />
		<property name="age" value="28" />
	</bean>
	
</beans>

在一般情況下，引用這樣也沒(méi)有問(wèn)題，但由于“yiibai” persion bean 只用于Customer bean，這是更好地聲明 “yiibai” person 作為一個(gè)內(nèi)部 bean，如下：

<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-2.5.xsd">

	<bean id="CustomerBean" class="com.yiibai.common.Customer">
		<property name="person">
			<bean class="com.yiibai.common.Person">
				<property name="name" value="yiibai" />
				<property name="address" value="address1" />
				<property name="age" value="28" />
			</bean>
		</property>
	</bean>
</beans>

內(nèi)部 bean 也支持構(gòu)造器注入如下：

<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-2.5.xsd">

	<bean id="CustomerBean" class="com.yiibai.common.Customer">
		<constructor-arg>
			<bean class="com.yiibai.common.Person">
				<property name="name" value="yiibai" />
				<property name="address" value="address1" />
				<property name="age" value="28" />
			</bean>
		</constructor-arg>
	</bean>
</beans>

注意：

id 或 name 值在bean類(lèi)是沒(méi)有必要以一個(gè)內(nèi)部 bean 呈現(xiàn)，它會(huì)簡(jiǎn)單地忽略Spring容器。

執(zhí)行結(jié)果：

package com.yiibai.common;

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

public class App 
{
    public static void main( String[] args )
    {
    	ApplicationContext context = 
    	  new ClassPathXmlApplicationContext(new String[] {"Spring-Customer.xml"});

    	Customer cust = (Customer)context.getBean("CustomerBean");
    	System.out.println(cust);
     
    }
}

輸出結(jié)果：

Customer [person=Person [address=address1, age=28, name=yiibai]]

上一篇：ListFactoryBean實(shí)例下一篇：Spring+Hibernate+MySql實(shí)例(注解)