项目包结构:
src/main/java
com.bonc.pojo--|-CompactDisc.java (接口)
|-SgtPeppers.java (实现类 实现 CompactDisc)
|-BlankDisc.java (实现类 实现 CompactDisc)
|-MediaPlayer.java (接口)
|-CDPlayer.java (实现类 实现 MediaPlayer)
src/main/resources
spring.xml (Spring应用上下文配置信息)
接口 CompactDisc.java
package com.bonc.pojo; public interface CompactDisc { void play(); }
实现类 SgtPeppers.java
package com.bonc.pojo; public class SgtPeppers implements CompactDisc { private String title = "Sgt. Pepper's Lonely Hearts Club Band"; private String artist = "The Beatles"; public void play() { System.out.println("Playing "+title+"by"+artist); } public SgtPeppers() { super(); } //自定义带参构造器 public SgtPeppers(String title,String artist) { super(); this.title = title; this.artist = artist; } }实现类 BlankDisc.java
package com.bonc.pojo; import java.util.List; public class BlankDisc implements CompactDisc { private String title; private String artist; private List<String> tracks; public void play() { System.out.println("Playing "+title+" by "+artist); for(String track:tracks){ System.out.println("-Track: "+track); } } //自定义带参构造器 public BlankDisc(String title,String artist,List<String> tracks) { super(); this.title = title; this.artist = artist; this.tracks = tracks; } public String getTitle() { return title; } public void setTitle(String title) { this.title = title; } public String getArtist() { return artist; } public void setArtist(String artist) { this.artist = artist; } public List<String> getTracks() { return tracks; } public void setTracks(List<String> tracks) { this.tracks = tracks; } }接口 MediaPlayer.java
package com.bonc.pojo; public interface MediaPlayer { void play(); }实现类CDPlayer.java
package com.bonc.pojo; public class CDPlayer implements MediaPlayer{ private CompactDisc cd; public CDPlayer(){ super(); } public CDPlayer(CompactDisc cd){ this.cd = cd; } public void play() { cd.play(); } public void setCd(CompactDisc cd) { this.cd = cd; } }
Spring.xml配置信息
<?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:c="http://www.springframework.org/schema/c" xmlns:p="http://www.springframework.org/schema/p" xmlns:util="http://www.springframework.org/schema/util" 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-4.0.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.0.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-4.0.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsd http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util.xsd"> <!-- 一、XML配置说明: 在Spring刚刚出现的时候,XML是描述配置的主要方式。 尽管Spring长期以来确实与XML有着关联,但需要说明的是,XML不再是配置Spring的唯一方案。 鉴于已经存在那么多基于XML的Spring配置,所以理解如何在Spring中配置XML还是很重要的。 本篇文章在于帮助你维护已有的XML配置,在完成新的Spring工作时,希望你使用自动化配置和JavaConfig 如果不给出ID属性,这个bean会根据全限定类名来进行命名 本例中为 com.bonc.pojo.SgtPeppers#0 #0是一个计数的形式,用来区分其他相同类型的bean --> <bean id="compactDisc" class="com.bonc.pojo.SgtPeppers"/> <!-- 二、借助构造器初始化bean有两种方案: 1. <constructor-arg>元素 2. 使用Spring3.0所引入的c-命名空间 --> <bean id="cdPlayer" class="com.bonc.pojo.CDPlayer"> <constructor-arg ref="compactDisc"/> </bean> <!-- c:cd-ref c(命名空间的前缀)-构造器的参数名-ref(告诉Spring 正在装配的是一个bean的引用) 也可以使用参数在参数列表中的位置信息 c:_0-ref="compactDisc" --> <bean id="cdPlayer2" class="com.bonc.pojo.CDPlayer" c:cd-ref="compactDisc"/> <!-- 装配字面量 --> <bean id="compactDisc" class="com.bonc.pojo.SgtPeppers"> <constructor-arg value="Sgt. Pepper's Lonely Hearts Club Band"/> <constructor-arg value="The Beatles"/> </bean> <bean id="compactDisc" class="com.bonc.pojo.SgtPeppers" c:_title="gt. Pepper's Lonely Hearts Club Band" c:_artist="The Beatles"/> <bean id="compactDisc" class="com.bonc.pojo.SgtPeppers" c:_0="gt. Pepper's Lonely Hearts Club Band" c:_1="The Beatles"/> <!-- 装配list --> <bean id="compactDisc" class="com.bonc.pojo.BlankDisc"> <constructor-arg value="Sgt. Pepper's Lonely Hearts Club Band"/> <constructor-arg value="The Beatles"/> <constructor-arg> <list> <value>Sgt.Pepper's warm heart</value> <value>With a little help from My Friends</value> <value>in the Sky with Diamonds</value> <value>Getting Better</value> <value>Fixing A Hole</value> </list> </constructor-arg> </bean> <!-- 装配set --> <bean id="compactDisc" class="com.bonc.pojo.BlankDisc"> <constructor-arg value="Sgt. Pepper's Lonely Hearts Club Band"/> <constructor-arg value="The Beatles"/> <constructor-arg> <set> <value>Sgt.Pepper's warm heart</value> <value>With a little help from My Friends</value> <value>in the Sky with Diamonds</value> <value>Getting Better</value> <value>Fixing A Hole</value> </set> </constructor-arg> </bean> <!-- 三、属性初始化bean --> <bean id="compactDisc" class="com.bonc.pojo.BlankDisc"> <property name="title" value="Sgt. Pepper's Lonely Hearts Club Band"/> <property name="artist"value="The Beatles"/> <property name="tracks"> <list> <value>Sgt.Pepper's warm heart</value> <value>With a little help from My Friends</value> <value>in the Sky with Diamonds</value> <value>Getting Better</value> <value>Fixing A Hole</value> </list> </property> </bean> <!-- 四、使用Spring util-命名空间简化bean配置 首先需要在XML中声明util-命名空间及其模式 util:list只是util-命名空间中的多个元素之一 --> <util:list id="trackList"> <value>Sgt.Pepper's warm heart</value> <value>With a little help from My Friends</value> <value>in the Sky with Diamonds</value> <value>Getting Better</value> <value>Fixing A Hole</value> </util:list> <bean id="compactDisc" class="com.bonc.pojo.BlankDisc" p:title="Sgt. Pepper's Lonely Hearts Club Band" p:artist="The Beatles" p:track-ref="trackList"/> </beans>