spring_配置处理器对象、处理器映射器、处理器适配器、视图解析器

创建spring配置文件：application-context.xml。

创建处理器类

package com.lanou.demo.controller;public class BookController implements Controller {
    @Override
    public ModelAndView handleRequest(HttpServletRequest request, HttpServletResponse response) throws Exception {
}
}

public class OrderServlet extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        System.out.println("OrderServlet.doGet");
    }
}

public class UserHandller implements HttpRequestHandler {
    @Override
    public void handleRequest(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        System.out.println("UserHandller.handleRequest");
    }
}

1.配置处理器对象：

第一种：

  <bean id="/book.do" class="com.lanou.demo.controller.BookController"/>

第二种：

    <bean id="book1" class="com.lanou.demo.controller.BookController"/>
    <bean id="orderServlet" class="com.lanou.demo.controller.OrderServlet"/>
    <bean id="userHandller" class="com.lanou.demo.controller.UserHandller"/>
    <bean id="controller" class="com.lanou.demo.controller.CategoryController"/>

2.配置处理器映射器：HandlerMapping

第一种：这个处理器映射是根据Handler的bean的名字（也就是id）来进行映射的

<bean class="org.springframework.web.servlet.handler.BeanNameUrlHandlerMapping"/>

第二种：简单Url映射

<bean class="org.springframework.web.servlet.handler.SimpleUrlHandlerMapping">
        <property name="mappings">
            <props>
                <prop key="/book/1">book1</prop>
                <prop key="/book/2">book1</prop>
                <prop key="/order">orderServlet</prop>
                <prop key="/user">userHandller</prop>
            </props>
        </property>
    </bean>

第三种:注解形式:

<bean class="org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping"/>

配合Controller层的方法上注解@RequestMapping("/url")使用.

3.配置处理器适配器:HandlerAdapter.

    <!--处理Servlet实现类类型的Handller 3-->
    <bean class="org.springframework.web.servlet.handler.SimpleServletHandlerAdapter"/>
    <!--处理Controller实现类型的Handler 1-->
    <bean class="org.springframework.web.servlet.mvc.SimpleControllerHandlerAdapter"/>

    <!--处理HttpRequestHandller实现类类型的Handller 4-->
    <bean class="org.springframework.web.servlet.mvc.HttpRequestHandlerAdapter"/>

   <!--处理RequestMapping注解形式的Handller 2--> 
   <bean class="org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter"/> 

4.配置视图解析器:

 <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver" id="viewResolver">
        <!--视图的前缀-->
        <property name="prefix" value="/视图前缀(即前端网页存放的位置)/"/>
        <!--视图的后缀-->
        <property name="suffix" value="视图后缀(即网页类型:.jsp或.html)"/>

    </bean>