Spring 加载方式
对于可执行文件方式，我们一般的加载Spring 配置的方式是
ClassPathXmlApplicationContext
public static void main(String[] args) {
ClassPathXmlApplicationContext xmlApplicationContext = new ClassPathXmlApplicationContext("classpath:spring-context.xml");
DemoService demoService = (DemoService) xmlApplicationContext.getBean("demoService");
String text = demoService.hello();
System.out.println(text);
}
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.2.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-3.2.xsd"
default-autowire="byName" default-lazy-init="false">
<!-- 采用注释的方式配置bean -->
<context:annotation-config/>
<!-- 配置要扫描的包 -->
<context:component-scan base-package="com.jin.lesson.context"/>
</beans>
从spring 3.0开始，开始使用注解的方式来进行spring 配置的注册
public static void main(String[] args) {
AnnotationConfigApplicationContext annotationConfigApplicationContext = new AnnotationConfigApplicationContext();
// 告诉要扫描的包，通常是应用的根目录的Application类
annotationConfigApplicationContext.scan(Main.class.getPackage().getName());
// 刷新上下文，使用得相应的bean注册成功
annotationConfigApplicationContext.refresh();
// 通过名称的方式获取相应的DemoService
DemoService demoService = (DemoService) annotationConfigApplicationContext.getBean("demoService");
String text = demoService.hello();
System.out.println(text);
}
demoService是定义的一个Service的名称,xml配置的方式也是可以设定好是否采用注解的方式进行扫描，如1中的
<context:annotation-config/>
demoService 很简单，如下的方式
@Service(value = "demoService")
public class DemoService {
public String hello() {
return "hello world";
}
}
Web应用的初始化
web.xml 配置方式
利用spring 自带的Servlet 进行初始注册
<servlet>
<servlet-name>SpringMVC</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<init-param>
<param-name>contextConfigLocation</param-name>
<param-value>classpath:spring/spring-context.xml</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
<async-supported>true</async-supported>
</servlet>
<servlet-mapping>
<servlet-name>SpringMVC</servlet-name>
<url-pattern>/</url-pattern>
</servlet-mapping>
利用 Listener进行注册 ,像Spring+structs，就是以这种方式来初始化上下文内容的
<listener>
<listener-class>
org.springframework.web.context.ContextLoaderListener
</listener-class>
</listener>
<listener>
<listener-class>org.springframework.web.context.request.RequestContextListener</listener-class>
</listener>
注解的方式
也是利用Servlet的方式来配置初始化参数，不过这次里要用基于注解的类AnnotationConfigWebApplicationContext,同时要注册Servlet
@Override
public void onStartup(ServletContext servletContext) throws ServletException {
ServletRegistration.Dynamic dispatcher = servletContext.addServlet("dispatcher", DispatcherServlet.class);
dispatcher.setInitParameter("contextConfigLocation", getClass().getName());
dispatcher.setInitParameter("contextClass", AnnotationConfigWebApplicationContext.class.getName());
dispatcher.addMapping("/*");
dispatcher.setLoadOnStartup(1);
}
