spring-bean命名方式-以及实例化--配置文件整合

Spring 配置文件的一般结构如下：

•<beans>

•    <import  resource=“resource1.xml” />

•    <import  resource=“resource2.xml” />

•    <bean id=“bean1” class=“***”></bean>

•    <bean name=“bean2” class=“***”></bean>

•    <alias alias=“bean3”name=“bean2”/>

•</beans>

其中import是导入其他配置。

以上实例代码为：

1、命名

首先是接口类：

public interface HelloWorld {public void sayHello();}

然后是实现类：

public class HelloWorldImpl implements HelloWorld {@Overridepublic void sayHello() {System.out.println("Hello World!");}}

spring命名实例：

<?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 class="com.jike.spring.chapter04.definition.HelloWorldImpl" /><bean id="helloWorld" class="com.jike.spring.chapter04.definition.HelloWorldImpl" /><bean name="helloWorldByName" class="com.jike.spring.chapter04.definition.HelloWorldImpl" /><bean id="helloWorldById" name="helloWorldByName01" class="com.jike.spring.chapter04.definition.HelloWorldImpl" /><bean name="bean1;alias11;alias12;alias13"class="com.jike.spring.chapter04.definition.HelloWorldImpl" /><bean id="bean2" name="alias21,alias22,alias23"class="com.jike.spring.chapter04.definition.HelloWorldImpl" /><bean name="bean3" class="com.jike.spring.chapter04.definition.HelloWorldImpl" /><alias alias="alias31" name="bean3" /><alias alias="alias32" name="bean3" /></beans>

2、实例化示例代码

首先是接口类：

public interface HelloWorld {public void sayHello();}

实现类：

public class HelloWorldImpl implements HelloWorld {    private String message;    /**     * 空构造器     */    public HelloWorldImpl() {        this.message = "Hello World!";    }    /**     * 带参构造器     *      * @param message     */    public HelloWorldImpl(String message) {        this.message = message;    }    public void sayHello() {        System.out.println(message);    }}

构造器实例化不需要类。
下面是静态工厂实例化类：

public class HelloWorldStaticFactory { /**     * 工厂方法      *      * @param message     * @return     */    public static HelloWorld newInstance(String message) {        // 返回需要的Bean实例        return new HelloWorldImpl(message);    }}

下面是实例工厂实例化类：

public class HelloWorldInstanceFactory {      /**     * 工厂方法      *      * @param message     * @return     */    public HelloWorld newInstance(String message) {        // 返回需要的Bean实例        return new HelloWorldImpl(message);    }}

最后是实例化的spring配置文件：

<?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">  <!--使用默认构造参数-->     <bean id="helloWorldWithNoArgs"     class="com.jike.spring.chapter04.instance.HelloWorldImpl" />    <!--使用有参数构造参数-->      <bean id="helloWorldWithArgs"     class="com.jike.spring.chapter04.instance.HelloWorldImpl" >        <!-- 指定构造器参数 -->          <constructor-arg index="0" value="Hello Args!"/>      </bean>            <!--静态工厂方式-->      <bean id="helloWorldStaticFactory"      class="com.jike.spring.chapter04.instance.HelloWorldStaticFactory"      factory-method="newInstance" >        <!-- 指定构造器参数 -->          <constructor-arg index="0" value="Hello Static Factory!"/>      </bean>        <!-- 1、定义实例工厂Bean -->    <bean id="helloWorldInstanceFactory"     class="com.jike.spring.chapter04.instance.HelloWorldInstanceFactory" />    <!-- 2、使用实例工厂Bean创建Bean -->    <bean id="helloWorldInstance" factory-bean="helloWorldInstanceFactory" factory-method="newInstance">         <constructor-arg index="0" value="Hello Instance Factory!"></constructor-arg>    </bean>    </beans>

最后是测试代码：

import org.springframework.beans.factory.BeanFactory;import org.springframework.context.support.ClassPathXmlApplicationContext;public class Main {public static void main(String[] args) {helloWorldInstanceFactory();}//使用无参数构造器来实例化Beanpublic static void sayHelloWithNoArgs() {BeanFactory beanFactory = new ClassPathXmlApplicationContext("conf/conf-instance.xml");HelloWorld helloWorld = beanFactory.getBean("helloWorldWithNoArgs", HelloWorld.class);helloWorld.sayHello();}//使用有参数构造器来实例化Beanpublic static void sayHelloWithArgs() {BeanFactory beanFactory = new ClassPathXmlApplicationContext("conf/conf-instance.xml");HelloWorld helloWorld = beanFactory.getBean("helloWorldWithArgs", HelloWorld.class);helloWorld.sayHello();}//使用静态工厂方法来实例化Bean    public static void helloWorldStaticFactory() {        // 1、读取配置文件实例化一个IOC容器    BeanFactory beanFactory =         new ClassPathXmlApplicationContext("conf/conf-instance.xml");        // 2、从容器中获取Bean，注意此处完全“面向接口编程，而不是面向实现”    HelloWorld helloWorld     = beanFactory.getBean("helloWorldStaticFactory", HelloWorld.class);        // 3、执行业务逻辑    helloWorld.sayHello();    }    //使用实例化工厂方法来实例化Bean    public static void helloWorldInstanceFactory() {        // 1、读取配置文件实例化一个IOC容器    BeanFactory beanFactory =         new ClassPathXmlApplicationContext("conf/conf-instance.xml");        // 2、从容器中获取Bean，注意此处完全“面向接口编程，而不是面向实现编程”    HelloWorld helloWorld     = beanFactory.getBean("helloWorldInstance", HelloWorld.class);        // 3、执行业务逻辑    helloWorld.sayHello();    }}