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关于网站建设的知识,湛江建设局网站,网站备案前置审批文件,网络营销与直播电商主要学什么如何使用以上的注解呢#xff1f; 第一步#xff1a;加入aop的依赖#xff08;已经包在context包里面#xff09;第二步#xff1a;在配置文件中添加context命名空间第三步#xff1a;在配置文件中指定扫描的包第四步#xff1a;在Bean类上使用注解 第一步#xff1a;加…如何使用以上的注解呢第一步加入aop的依赖已经包在context包里面第二步在配置文件中添加context命名空间第三步在配置文件中指定扫描的包第四步在Bean类上使用注解第一步加入aop的依赖我们可以看到当加入spring-context依赖之后会关联加入aop的依赖。所以这一步不用做。第二步在配置文件中添加context命名空间?xml version1.0 encodingUTF-8?beansxmlnshttp://www.springframework.org/schema/beansxmlns:xsihttp://www.w3.org/2001/XMLSchema-instancexmlns:contexthttp://www.springframework.org/schema/contextxsi:schemaLocationhttp://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd/beans第三步在配置文件中指定要扫描的包?xml version1.0 encodingUTF-8?beansxmlnshttp://www.springframework.org/schema/beansxmlns:xsihttp://www.w3.org/2001/XMLSchema-instancexmlns:contexthttp://www.springframework.org/schema/contextxsi:schemaLocationhttp://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsdcontext:component-scanbase-packagecom.powernode.spring6.bean//beans第四步在Bean类上使用注解packagecom.powernode.spring6.bean;importorg.springframework.stereotype.Component;Component(valueuserBean)publicclassUser{}编写测试程序packagecom.powernode.spring6.test;importcom.powernode.spring6.bean.User;importorg.junit.Test;importorg.springframework.context.ApplicationContext;importorg.springframework.context.support.ClassPathXmlApplicationContext;publicclassAnnotationTest{TestpublicvoidtestBean(){ApplicationContextapplicationContextnewClassPathXmlApplicationContext(spring.xml);UseruserBeanapplicationContext.getBean(userBean,User.class);System.out.println(userBean);}}如果注解的属性名是value那么value是可以省略的。packagecom.powernode.spring6.bean;importorg.springframework.stereotype.Component;Component(vipBean)publicclassVip{}packagecom.powernode.spring6.test;importcom.powernode.spring6.bean.Vip;importorg.junit.Test;importorg.springframework.context.ApplicationContext;importorg.springframework.context.support.ClassPathXmlApplicationContext;publicclassAnnotationTest{TestpublicvoidtestBean(){ApplicationContextapplicationContextnewClassPathXmlApplicationContext(spring.xml);VipvipBeanapplicationContext.getBean(vipBean,Vip.class);System.out.println(vipBean);}}如果把value属性彻底去掉spring会被Bean自动取名吗会的。并且默认名字的规律是Bean类名首字母小写即可。packagecom.powernode.spring6.bean;importorg.springframework.stereotype.Component;ComponentpublicclassBankDao{}也就是说这个BankDao的bean的名字为bankDao测试一下packagecom.powernode.spring6.test;importcom.powernode.spring6.bean.BankDao;importorg.junit.Test;importorg.springframework.context.ApplicationContext;importorg.springframework.context.support.ClassPathXmlApplicationContext;publicclassAnnotationTest{TestpublicvoidtestBean(){ApplicationContextapplicationContextnewClassPathXmlApplicationContext(spring.xml);BankDaobankDaoapplicationContext.getBean(bankDao,BankDao.class);System.out.println(bankDao);}}我们将Component注解换成其它三个注解看看是否可以用packagecom.powernode.spring6.bean;importorg.springframework.stereotype.Controller;ControllerpublicclassBankDao{}剩下的两个注解大家可以测试一下。如果是多个包怎么办有两种解决方案第一种在配置文件中指定多个包用逗号隔开。第二种指定多个包的共同父包。先来测试一下逗号英文的方式创建一个新的包bean2定义一个Bean类。packagecom.powernode.spring6.bean2;importorg.springframework.stereotype.Service;ServicepublicclassOrder{}配置文件修改?xml version1.0 encodingUTF-8?beansxmlnshttp://www.springframework.org/schema/beansxmlns:xsihttp://www.w3.org/2001/XMLSchema-instancexmlns:contexthttp://www.springframework.org/schema/contextxsi:schemaLocationhttp://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsdcontext:component-scanbase-packagecom.powernode.spring6.bean,com.powernode.spring6.bean2//beans测试程序packagecom.powernode.spring6.test;importcom.powernode.spring6.bean.BankDao;importcom.powernode.spring6.bean2.Order;importorg.junit.Test;importorg.springframework.context.ApplicationContext;importorg.springframework.context.support.ClassPathXmlApplicationContext;publicclassAnnotationTest{TestpublicvoidtestBean(){ApplicationContextapplicationContextnewClassPathXmlApplicationContext(spring.xml);BankDaobankDaoapplicationContext.getBean(bankDao,BankDao.class);System.out.println(bankDao);OrderorderapplicationContext.getBean(order,Order.class);System.out.println(order);}}我们再来看看指定共同的父包行不行?xml version1.0 encodingUTF-8?beansxmlnshttp://www.springframework.org/schema/beansxmlns:xsihttp://www.w3.org/2001/XMLSchema-instancexmlns:contexthttp://www.springframework.org/schema/contextxsi:schemaLocationhttp://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsdcontext:component-scanbase-packagecom.powernode.spring6//beans