Handler

Posted 2020-08-25 2226016500

1.Handler
实现Handler第二种和第三种
1.1 继承AbstractController
优点：能定制请求方式

package cn.happyl.controller;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.springframework.web.servlet.ModelAndView;
import org.springframework.web.servlet.mvc.AbstractController;
import org.springframework.web.servlet.mvc.Controller;
import org.springframework.web.servlet.support.WebContentGenerator;

public class MyAbstract extends AbstractController {
    @Override
    protected ModelAndView handleRequestInternal(HttpServletRequest request,
            HttpServletResponse response) throws Exception {
        ModelAndView mv =new ModelAndView();
        mv.setViewName("index");
        mv.addObject("msg","今天学习spring mvc");
        return mv;
    }
}

application.xml

 <bean id="first" class="cn.happyl.controller.MyAbstract">
            <property name="supportedMethods" value="POST,GET"></property>
        
        </bean>

<!--试图解析器 -->
<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<property name="prefix" value="/WEB-INF/"></property>
<property name="suffix" value=".jsp"></property>
</bean>

 

 

 

<bean class="org.springframework.web.servlet.handler.SimpleUrlHandlerMapping">
<property name="mappings">
<props>
<prop key="/hello.do">first</prop>
</props>
</property>
</bean>

 

 

1.2 继承MultiActionController
优点：可以在一个Controller中有N个方法

 

package cn.happyl.controller;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.springframework.web.servlet.ModelAndView;
import org.springframework.web.servlet.mvc.multiaction.MultiActionController;


public class MyMultiAction extends MultiActionController {
    public ModelAndView doFirst(HttpServletRequest request,HttpServletResponse response){
        ModelAndView mv =new ModelAndView();
        mv.setViewName("index");
        mv.addObject("msg", "执行第一个方法");
        return mv;
    }
    public ModelAndView doSecond(HttpServletRequest request,HttpServletResponse response){
        ModelAndView mv =new ModelAndView();
        mv.setViewName("index");
        mv.addObject("msg", "执行第二个方法");
        return mv;
    }
    
}

 

 

 application.xml

方法一：ParameterMethodNameResolver

 <bean id="first" class="cn.happyl.controller.MyMultiAction">
            <property name="methodNameResolver" ref="methodNameResolver"></property>
        </bean>



   <bean id="methodNameResolver" class="org.springframework.web.servlet.mvc.multiaction.ParameterMethodNameResolver">
　　          
 <property name="paramName" value="actionname"></property>
       
       </bean>

 可以访问：

 http://localhost:8080/01-springmvc-base/hello.do?actionname=doSecond

 http://localhost:8080/01-springmvc-base/hello.do?actionname=doFirst

如果不配置

 <property name="paramName" value="actionname"></property>
默认value为action

 

在访问多方法时：默认为InternalPathMethodNameResolver(属于AbstractUrlMethodNameResolver)

访问时：http://localhost:8080/01-springmvc-base/doSecond.do

直接写方法名.do即可

方法二：propertiesmethodnameresolver 用法如下：
在applicationContext.xml中配置

<bean class="org.springframework.web.servlet.handler.SimpleUrlHandlerMapping">
　　<property name="mappings">
　　　　<props>
　　　　　　<prop key="/*.do">first</prop>
　　　　</props>
　　</property>　　
</bean>

<bean id="methodNameResolver" class="org.springframework.web.servlet.mvc.multiaction.PropertiesMethodNameResolver">
               <property name="mappings">
                   <props>
                       <prop key="/first.do">doFirst</prop>
                       <prop key="/second.do">doSecond</prop>
                   </props>
               </property>
</bean>

可以再浏览器的get请求中写：http://localhost:8080/01-springmvc-base/first.do


试图解析器

<!--试图解析器 2 jstlview 内部资源-->
<bean id="internalResource" class="org.springframework.web.servlet.view.JstlView">
<property name="url" value="/WEB-INF/index.jsp"></property>
</bean>

<!--redirectView外部资源-->
<bean id="jd" class="org.springframework.web.servlet.view.RedirectView">
<property name="url" value="http://www.jd.com" ></property>
</bean>

 <bean class="org.springframework.web.servlet.view.BeanNameViewResolver"/>

 

测试类如下：

package cn.happyl.controller;


import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.springframework.web.servlet.ModelAndView;
import org.springframework.web.servlet.mvc.multiaction.MultiActionController;

public class BookController extends MultiActionController {

    public ModelAndView list(HttpServletRequest request,HttpServletResponse response){
        ModelAndView mv =new ModelAndView();
        mv.addObject("msg","我是谁?");
        //这里制定需要访问的资源的id，可以是内部资源也可以是外部资源
        mv.setViewName("jd");
        return mv;
    }

}