Sping in Action读书笔记之一----------Bean的各种注入操作

Spring in Action这本书可以说是非常好的一本讲解Spring框架的好书，现在出版了第三版，包含了Spring3.0的许多

新特性，特此拿来好好系统的学习一番，以前对Spring有所了解，但是不是非常的详细，现在打算好好的认真的研究一

下Spring，先从最基础的开始吧。

1.Declaring a simple bean

这里声明了一个非常简单的Bean然后使用Spring的依赖注入技术实现对他的调用。

package com.bird.springidol;/** * declaring a simple bean * @author Bird * */public class Juggler {private int beanBags = 3;public Juggler(){}public Juggler(int beanBags){this.beanBags=beanBags;}public void perform(){System.out.println("Juggling "+beanBags+" BEANBAGS");}}

只需要在XML文件中做如下配置

<?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-3.0.xsd" >  <bean id="duke" class="com.bird.springidol.Juggler"></bean>

然后使用Junti测试框架进行测试

/** * declaring a simple bean */@Testpublic void test1(){ApplicationContext ctx = new ClassPathXmlApplicationContext("beans.xml");Juggler ju = (Juggler) ctx.getBean("duke");ju.perform();}

2.injecting through constructors

通过构造函数传入参数的注入方式

还是刚才的那个代码，这里使用了不同的配置方式

<bean id="duke1" class="com.bird.springidol.Juggler">  <constructor-arg value="15"></constructor-arg>  </bean>

测试代码如下

/** * Injecting through constructors */@Testpublic void test2(){ApplicationContext ctx = new ClassPathXmlApplicationContext("beans.xml");Juggler ju = (Juggler) ctx.getBean("duke1");ju.perform();}

3.injecting object references with constructors

通过构造函数传入对象

package com.bird.springidol;/** * injecting object references with constructors * @author Administrator * */public class Poeticjuggler extends Juggler {private Poem poem;//倚赖注入的public Poeticjuggler(Poem poem){super();this.poem=poem;}public Poeticjuggler(int beanBags, Poem poem){super(beanBags);this.poem=poem;}public void perform(){super.perform();System.out.println("whing reciting.....");poem.recite();}}

package com.bird.springidol;public class Sonnect29 implements Poem {@Overridepublic void recite() {System.out.println("this is a poem that too long");}}

配置方式如下

<bean id="sonnet29" class="com.bird.springidol.Sonnect29"></bean>      <bean id="poeticDuke" class="com.bird.springidol.Poeticjuggler">   <constructor-arg value="15"></constructor-arg>   <constructor-arg ref="sonnet29"></constructor-arg>   </bean>

4.creating beans through factory methods

很多类使用单例设计模式，这样的对象只能通过静态方法生成一个对象，这里说一下如何注入这些对象

package com.bird.springidol;/** * creating beans through factory methods * @author Administrator * */public class Staage {private Staage(){}private static class StageSingletonHolder{static Staage instance = new Staage();}public static Staage getInstance(){return StageSingletonHolder.instance;}}

 <bean id="theStage" class="com.bird.springidol.Staage" factory-method="getInstance"></bean>

5.initializing and destorying beans

在创建和删除Bean的时候调用的代码

只需要这样配置

<bean id="test1" class="" init-method="" destroy-method=""></bean>

6.injecting into bean properties

注入对象的属性

package com.bird.springidol;/** * injecting into bean properties *  * @author Administrator *  */public class Instrumentalist {private String song;private Instrument instrument;public String getSong() {return song;}public void setSong(String song) {this.song = song;}public Instrument getInstrument() {return instrument;}public void setInstrument(Instrument instrument) {this.instrument = instrument;}public Instrumentalist(){}public void perform(){System.out.println("playing"+song+":");instrument.play();}}

package com.bird.springidol;public class Saxophone implements Instrument {public Saxophone(){}@Overridepublic void play() {System.out.println("TOOT TOOT TOOT");}}

配置如下

 <bean id="saxophone" class="com.bird.springidol.Saxophone"></bean>   <bean id="kenny" class="com.bird.springidol.Instrumentalist">   <property name="song" value="Jingle Bells"></property>   <property name="instrument" ref="saxophone"></property>   </bean>