1. 程式人生 > >spring靜態工廠和例項工廠的區別

spring靜態工廠和例項工廠的區別

新聞實體類NewsBean

package com.tang;

/**
 * 新聞實體類
 */
public class News {
    String title;
    String content;

    @Override
    public String toString() {
        return "News{" +
                "title='" + title + '\'' +
                ", content='" + content + '\'' +
                '}';
    }

    public String getTitle() {
        return title;
    }

    public void setTitle(String title) {
        this.title = title;
    }

    public String getContent() {
        return content;
    }

    public void setContent(String content) {
        this.content = content;
    }

    public News(String title, String content) {

        this.title = title;
        this.content = content;
    }

    public News() {

    }
}

例項工廠方法

package com.tang;

import java.util.HashMap;
import java.util.Map;

/**
 * 例項工廠
 */
public class InstanceFactory {
    Map<String,News> newsMap = new HashMap<String,News>();

    public InstanceFactory(){
        newsMap.put("news1",new News("InstanceFactory標題1","內容1"));
        newsMap.put("news2",new News("InstanceFactory標題2","內容2"));
    }

    public News getNews(String name){
        return newsMap.get(name);
    }
}

靜態工廠方法

package com.tang;

import java.util.HashMap;
import java.util.Map;

/**
 * 靜態工廠
 */
public class StaticFactory {
    private static Map<String,News> newsMap = new HashMap<String,News>();
    static {
        newsMap.put("news1",new News("StaticFactory標題1","內容1"));
        newsMap.put("news2",new News("StaticFactory標題2","內容2"));
    }

    public static News getNews(String name){
        return newsMap.get(name);
    }
}

xml配置

<?xml version="1.0" encoding="UTF-8"?>
<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.xsd">

    <!--靜態工廠方法 工廠不需要例項化-->
    <bean id="news11" class="com.tang.StaticFactory" factory-method="getNews">
        <constructor-arg value="news1"/>
    </bean>
    <bean id="news12" class="com.tang.StaticFactory" factory-method="getNews">
        <constructor-arg value="news2"/>
    </bean>

    <!--例項工廠方法是先將工廠例項化-->
    <bean id="instanceFactory" class="com.tang.InstanceFactory"/>

    <bean id="news21" factory-bean="instanceFactory" factory-method="getNews">
    <constructor-arg value="news1"/>
    </bean>
    <bean id="news22" factory-bean="instanceFactory" factory-method="getNews">
        <constructor-arg value="news2"/>
    </bean>
</beans>

main測試方法(使用單元測試的方法進行測試)

package com.tang;

import org.junit.Before;
import org.junit.Test;
import org.springframework.context.support.ClassPathXmlApplicationContext;

public class test {
    private ClassPathXmlApplicationContext ctx;

    @Before
    public void before() {
        //初始化Spring容器,當Spring容器初始化時,會自動載入配置檔案,然後根據配置檔案中的內容初始化Bean
        ctx = new ClassPathXmlApplicationContext("application.xml");
    }

    @Test
    public void test1() {
        News news11 = (News) ctx.getBean("news11");
        System.out.println(news11);
        News news12 = (News) ctx.getBean("news12");
        System.out.println(news12);
    }

    @Test
    public void test2() {
        News news21 = (News) ctx.getBean("news21");
        System.out.println(news21);
        News news22 = (News) ctx.getBean("news22");
        System.out.println(news22);
    }
}

測試結果

test1:

News{title='StaticFactory標題1', content='內容1'}
News{title='StaticFactory標題2', content='內容2'}

Process finished with exit code 0

test2:

News{title='InstanceFactory標題1', content='內容1'}
News{title='InstanceFactory標題2', content='內容2'}

Process finished with exit code 0