REST即表述性状态传递（英文：Representational State Transfer，简称REST）是Roy Fielding博士在2000年他的博士论文中提出来的一种软件架构风格。它是一种针对网络应用的设计和开发方式，可以降低开发的复杂性，提高系统的可伸缩性。一种相较与之前URL所产生一种更优雅的URL风格.
查询用户: http://localhost:8080/xxx/user/1 GET —查询
查询多个用户: http://localhost:8080/xxx/users GET
新增用户: http://localhost:8080/xxx/user POST —-新增
修改用户: http://localhost:8080/xxx/user/1 PUT —修改
删除用户:http://localhost:8080/xxx/user/1 DELETE —删除
1.Rest风格
Controller
package com.xixi.controller;import com.xixi.pojo.User;import org.springframework.stereotype.Controller;import org.springframework.web.bind.annotation.*;/*** JSPs only permit GET POST or HEAD* 解决：* 1.需要添加HiddenHttpMethodFilter过滤器* 2。在表单中添加隐藏域： <input type="hidden" name="_method" value="put"/> value就是对应的请求方式* 3。将form表单修改成POST* 4。过滤器自动将隐藏域修改成value的值。**** Tomcat7以上对request method更为严格，只支持GET/POST* 1.使用Tomcat7* 2.不用转发，使用重定向 return "redirect:/index.jsp";* 3. 将jsp的page指定 isErrorPage属性改成true(不建议)* 4。自定义一个过滤器，将request.method改回POST**/@Controller@RequestMapping("/rest")public class RestController {@GetMapping("/user/{id}")public String get(@PathVariable("id") Integer id){System.out.println("查询用户："+id);return "/index.jsp";}// 新增@PostMapping("/user")public String add(User user){System.out.println("新增用户："+user);return "/index.jsp";}//修改@PutMapping("/user/{id}")public String update(User user){System.out.println("修改用户："+user);return "/index.jsp";// return "redirect:/index.jsp";}//删除@DeleteMapping("/user/{id}")public String delete(@PathVariable("id") Integer id){System.out.println("删除用户："+id);return "/index.jsp";// return "redirect:/index.jsp";}}
2.rest.jsp
<%--
Created by IntelliJ IDEA.
User: yangkang
Date: 2021/11/11
Time: 20:47
To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<% request.setAttribute("basepath",request.getContextPath()); %>
<html>
<head>
<title>Title</title>
</head>
<body>
<form action="${basepath}/rest/user/1" method="get">
<input type="submit" value="查询"/>
</form>
<form action="${basepath}/rest/user" method="post">
id:<input type="text" name="id" />
姓名：<input type="text" name="name" />
<input type="submit" value="新增"/>
</form>
<!-- html不识别put和delete-->
<%--<form action="${basepath}/rest/user/1" method="put">--%>
<form action="${basepath}/rest/user/1" method="post">
id:<input type="text" name="id" />
姓名：<input type="text" name="name" />
<input type="submit" value="修改"/>
<input type="hidden" name="_method" value="put"/>
</form>
<%--<form action="${basepath}/rest/user/1" method="delete">--%>
<form action="${basepath}/rest/user/1" method="post">
<input type="submit" value="删除"/>
<input type="hidden" name="_method" value="delete"/>
</form>
</body>
</html>
3.web.xml
<?xml version="1.0" encoding="UTF-8"?>
<web-app 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_4_0.xsd"
version="4.0">
<!--DispatchServlet的配置 分发器 -->
<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-mvc.xml</param-value>
</init-param>
<!-- TOMCAT容器启动的时候下载-->
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>springmvc</servlet-name>
<url-pattern>/</url-pattern>
</servlet-mapping>
<!-- 从上往下加载filter-->
<filter>
<filter-name>characterEncodingFilter</filter-name>
<filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
<!--解决post请求乱码-->
<init-param>
<param-name>encoding</param-name>
<param-value>UTF-8</param-value>
</init-param>
<!--解决响应乱码-->
<init-param>
<param-name>forceEncoding</param-name>
<param-value>true</param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name>characterEncodingFilter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
<!-- 处理html中不支持rest中put和delete-->
<filter>
<filter-name>hiddenHttpMethodFilter</filter-name>
<filter-class>org.springframework.web.filter.HiddenHttpMethodFilter</filter-class>
</filter>
<filter-mapping>
<filter-name>hiddenHttpMethodFilter</filter-name>
<servlet-name>springmvc</servlet-name>
</filter-mapping>
<!-- 自定义一个过滤器，将request.method改回POST-->
<filter>
<filter-name>myFilter</filter-name>
<filter-class>com.xixi.GetMethodConvertingFilter</filter-class>
</filter>
<filter-mapping>
<filter-name>myFilter</filter-name>
<url-pattern>/*</url-pattern>
<dispatcher>FORWARD</dispatcher>
</filter-mapping>
</web-app>
3.自定义Filter解决PUT/DELETE回显报错
package com.xixi;
import javax.servlet.*;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;
import java.io.IOException;
/**
* @author yangkang
* @version 1.0
* @description: TODO
* @date 2021/11/12 00:59
*/
public class GetMethodConvertingFilter implements Filter {
@Override
public void init(FilterConfig filterConfig) throws ServletException {
}
@Override
public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
filterChain.doFilter(wrapperRequest((HttpServletRequest) servletRequest),servletResponse);
}
@Override
public void destroy() {
}
private HttpServletRequestWrapper wrapperRequest(HttpServletRequest request) {
return new HttpServletRequestWrapper(request){
@Override
public String getMethod() {
return "POST";
}
};
}
}
2.访问静态资源
此时大家发现我们请求的图片根本访问不到，根据查看发现路径是没有问题的，那么为什么会找不到静态资源呢？
大家发现此时是找不到对应的mapping映射的，此时是因为DispatcherServlet会拦截所有的请求，而此时我们没有对应图片的请求处理方法，所以此时报错了，想要解决的话非常简单，只需要添加一个配置即可.
2.1 spring-mvc.xml
<!--配置访问静态资源 -->
<mvc:annotation-driven/>
<!-- 1。将映射的路径指向静态资源文件夹，springmvc将不会将此作为handler处理（推荐）-->
<!-- <mvc:resources mapping="/images/**" location="/images/"></mvc:resources>-->
<!--2。当springmvc 没有映射到一个请求的时候交给tomcat默认的servlet处理 -->
<mvc:default-servlet-handler></mvc:default-servlet-handler>
若有收获，就点个赞吧
0 人点赞
