Spring 學習筆記(三)IOC之XML方式配置 第一回 javaBean的配置與獲取
阿新 • • 發佈:2018-12-16
IOC的兩種方式:
- XML方式
- 註解方式
XML方式
需要的jar包
spring-beans-4.3.3.RELEASE.jar
spring-context-4.3.3.RELEASE.jar
spring-context-support-4.3.3.RELEASE.jar
spring-core-4.3.3.RELEASE.jar
spring-expression-4.3.3.RELEASE.jar
1. 建立 applicationContext.xml配置檔案
<?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"> </beans>
2. 在beans目錄中增加要初始化的javaBean(bean標籤)
<?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"> <!--建立物件kazhafei--> <bean id="kazhafei" class="org.spring.example.Kazhafei" /> </beans>
3.開始測試
package org.spring.example; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.context.ApplicationContext; import org.springframework.context.support.AbstractApplicationContext; import org.springframework.context.support.ClassPathXmlApplicationContext; import org.springframework.context.support.FileSystemXmlApplicationContext; public class Test { public static void main(String[] args) { //初始化Spring IOC容器 ClassPathXmlApplicationContext:類路徑方式 推薦 ApplicationContext applicationContext = new ClassPathXmlApplicationContext("applicationContext.xml"); System.out.println("-----------------IOC初始化完畢-------------------"); //獲取Bean物件 People people1 = (People) applicationContext.getBean("kazhafei"); people1.getPeopleName(); } }
初始化SpringIOC容器的時候就會初始化好javaBean
從SpringIOC容器中獲取物件時,不會再執行構造方法(預設單例)