package pojo;

 public class Product {

     private int id;
     private String name;
     private Category category;   //引入Category对象同时添加get和set
     public int getId() {
         return id;
     }
     public void setId(int id) {
         this.id = id;
     }
     public String getName() {
         return name;
     }
     public void setName(String name) {
         this.name = name;
     }
     public Category getCategory() {
         return category;
     }
     public void setCategory(Category category) {
         this.category = category;
     }
 }

 <?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:aop="http://www.springframework.org/schema/aop"
     xmlns:tx="http://www.springframework.org/schema/tx" xmlns:context="http://www.springframework.org/schema/context"
     xsi:schemaLocation="
    http://www.springframework.org/schema/beans
    http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
    http://www.springframework.org/schema/aop
    http://www.springframework.org/schema/aop/spring-aop-3.0.xsd
    http://www.springframework.org/schema/tx
    http://www.springframework.org/schema/tx/spring-tx-3.0.xsd
    http://www.springframework.org/schema/context
    http://www.springframework.org/schema/context/spring-context-3.0.xsd">

     <bean name="c" class="pojo.Category">
         <property name="name" value="category 1" />
     </bean>
     <bean name="p" class="pojo.Product">
         <property name="name" value="product1" />
         <property name="category" ref="c" />
     </bean>

 </beans>

 package test;

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

 import pojo.Product;

 public class TestSpring {

     public static void main(String[] args) {
         ApplicationContext context = new ClassPathXmlApplicationContext(new String[] { "applicationContext.xml" });

         Product p = (Product) context.getBean("p");

         System.out.println(p.getName());
         System.out.println(p.getCategory().getName());
     }
 }