Spring实战——调用实例工厂方法创建Bean

我不是女神ヾ 2021-07-24 14:05 430阅读 0赞

**一 配置**

<?xml version="1.0" encoding="GBK"?>
    <beans xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xmlns="http://www.springframework.org/schema/beans"
         xsi:schemaLocation="http://www.springframework.org/schema/beans
         http://www.springframework.org/schema/beans/spring-beans-4.0.xsd">
         
         <bean id="personFactory"  class="org.crazyit.app.factory.PersonFactory"/>
         
         <bean id="chinese" factory-bean="personFactory"
               factory-method="getPerson">
               
               <constructor-arg value="chin"/>
         </bean>
         
         <bean id="american" factory-bean="personFactory"
               factory-method="getPerson">
               <constructor-arg value="ame"/>
         </bean>
    </beans>

**二 接口**

Person

package org.crazyit.app.service;
    
    public interface Person
    {
         // 定义一个打招呼的方法
         public String sayHello(String name);
         // 定义一个告别的方法
         public String sayGoodBye(String name);
    }

**三 实现类**

American

public class American implements Person
    {
         // 实现Person接口必须实现如下两个方法
         public String sayHello(String name)
         {
               return name + ",Hello!";
         }
         public String sayGoodBye(String name)
         {
               return name + ",Good Bye!";
         }
    }

Chinese

package org.crazyit.app.service.impl;
    import org.crazyit.app.service.*;
    
    public class Chinese implements Person
    {
         // 实现Person接口必须实现如下两个方法
         public String sayHello(String name)
         {
               return name + "，您好";
         }
         public String sayGoodBye(String name)
         {
               return name + "，下次再见";
         }
    }

**四 工厂类**

package org.crazyit.app.factory;
    
    
    import org.crazyit.app.service.*;
    import org.crazyit.app.service.impl.*;
    
    public class PersonFactory
    {
        // 获得Person实例的实例工厂方法
        // ethnic参数决定返回哪个Person实现类的实例
        public Person getPerson(String ethnic)
        {
            if (ethnic.equalsIgnoreCase("chin"))
            {
                return new Chinese();
            }
            else
            {
                return new American();
            }
        }
    }

**五 测试类**

package lee;
    
    
    import org.springframework.context.*;
    import org.springframework.context.support.*;
    
    
    import org.crazyit.app.service.*;
    
    public class SpringTest
    {
        public static void main(String[] args)
        {
            ApplicationContext ctx = new
                ClassPathXmlApplicationContext("beans.xml");
            Person p1 = ctx.getBean("chinese"
                , Person.class);
            System.out.println(p1.sayHello("Mary"));
            System.out.println(p1.sayGoodBye("Mary"));
            Person p2 = ctx.getBean("american"
                , Person.class);
            System.out.println(p2.sayHello("Jack"));
            System.out.println(p2.sayGoodBye("Jack"));
        }
    }

**六 测试**

Mary，您好
    Mary，下次再见
    Jack,Hello!
    Jack,Good Bye!