01-04、基于注解的 URL 映射

发布于 2025-03-09 23:21:24 字数 11327 浏览 0 评论 0 收藏 0

项目结构

创建项目 Pcrojet_0104 ，最终结构如下：

源码

applicationContext.xml

<?xml version='1.0' encoding='UTF-8' ?>
<beans xmlns="http://www.springframework.org/schema/beans"
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xmlns:p="http://www.springframework.org/schema/p"
     xmlns:aop="http://www.springframework.org/schema/aop"
     xmlns:tx="http://www.springframework.org/schema/tx"
     xmlns:context="http://www.springframework.org/schema/context"
     xmlns:mvc="http://www.springframework.org/schema/mvc"
     xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.0.xsd
     http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-4.0.xsd
     http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.0.xsd
     http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsd
     http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.0.xsd
     http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.0.xsd">

</beans>

该配置文件什么都没做。

dispatcher-servlet.xml

<?xml version='1.0' encoding='UTF-8' ?>
<beans xmlns="http://www.springframework.org/schema/beans"
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xmlns:p="http://www.springframework.org/schema/p"
     xmlns:aop="http://www.springframework.org/schema/aop"
     xmlns:tx="http://www.springframework.org/schema/tx"
     xmlns:context="http://www.springframework.org/schema/context"
     xmlns:mvc="http://www.springframework.org/schema/mvc"
     xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.0.xsd
     http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-4.0.xsd
     http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.0.xsd
     http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsd
     http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.0.xsd">

  <context:component-scan base-package="me.letiantian.controller" />
  <mvc:annotation-driven/>

  <bean class="org.springframework.web.servlet.mvc.support.ControllerClassNameHandlerMapping"/>

  <bean id="urlMapping" class="org.springframework.web.servlet.handler.SimpleUrlHandlerMapping">
    <property name="mappings">
      <props>
        <prop key="index">indexController</prop>
      </props>
    </property>
  </bean>

  <bean id="viewResolver"
      class="org.springframework.web.servlet.view.InternalResourceViewResolver"
      p:prefix="/WEB-INF/jsp/"
      p:suffix=".jsp" />

  <bean name="indexController"
      class="org.springframework.web.servlet.mvc.ParameterizableViewController"
      p:viewName="index" />

</beans>

<beans> 中增加了属性 xmlns:context 、 xmlns:mvc ，对应的在 xsi:schemaLocation 增加了:

http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsd
http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.0.xsd

关于 <mvc:annotation-driven/> 的意义，可参考 What's the difference between and in servlet? 。

web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app version="3.1" xmlns="http://xmlns.jcp.org/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd">
  <context-param>
    <param-name>contextConfigLocation</param-name>
    <param-value>/WEB-INF/applicationContext.xml</param-value>
  </context-param>
  <listener>
    <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
  </listener>
  <servlet>
    <servlet-name>dispatcher</servlet-name>
    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
    <load-on-startup>2</load-on-startup>
  </servlet>
  <servlet-mapping>
    <servlet-name>dispatcher</servlet-name>
    <url-pattern>/</url-pattern>
  </servlet-mapping>
  <session-config>
    <session-timeout>
      30
    </session-timeout>
  </session-config>
  <welcome-file-list>
    <welcome-file>redirect.jsp</welcome-file>
  </welcome-file-list>
</web-app>

模板文件

index.jsp：

<%@page contentType="text/html" pageEncoding="UTF-8"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
  "http://www.w3.org/TR/html4/loose.dtd">

<html>
  <head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
    <title>Welcome to Spring Web MVC project</title>
  </head>

  <body>
    <p>Hello! This is the default welcome page for a Spring Web MVC project.</p>
    <p><i>To display a different welcome page for this project, modify</i>
      <tt>index.jsp</tt> <i>, or create your own welcome page then change
        the redirection in</i> <tt>redirect.jsp</tt> <i>to point to the new
        welcome page and also update the welcome-file setting in</i>
      <tt>web.xml</tt>.</p>
  </body>
</html>

hello/method01.jsp：

<%@page contentType="text/html" pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
  <head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
    <title>JSP Page</title>
  </head>
  <body>
    <h1>Hello Method01</h1>
  </body>
</html>

hello/method04.jsp：

<%@page contentType="text/plain" pageEncoding="UTF-8"%>

name: ${name}

HelloController.java

package me.letiantian.controller;

import java.io.PrintWriter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;

@Controller
@RequestMapping("/hello")
public class HelloController{

  @RequestMapping(value = "")
  public String index() {
    return "index";
  }

  @RequestMapping(value = "/method01")
  public String method01() {
    return "hello/method01";
  }

  // 仅支持 HTTP POST 方法
  @RequestMapping(value = "/method02", method = {RequestMethod.POST})
  public String method02() {
    return "hello/method01";
  }

  @RequestMapping(value = "/method03")
  public void method03(HttpServletRequest request, HttpServletResponse response) {
    response.setContentType("text/plain;charset=UTF-8");
    try (PrintWriter out = response.getWriter()) {
      out.println("contextPath: " + request.getContextPath());
      out.println("name: " + request.getParameter("name"));
    } catch (Exception ex) {
      System.out.println(""+ex.getMessage());
    }
  }

  @RequestMapping(value = "/method04/{name}")
  public String method04(@PathVariable String name, Model model) {
    model.addAttribute("name", name);
    return "hello/method04";
  }

  @RequestMapping(value = "/method05/{id}")
  public String method05(@PathVariable int id, Model model) {
    model.addAttribute("name", id);
    return "hello/method04";
  }
}