HTTP 405 的错误提示:消息 JSP 只允许 GET、POST 或 HEAD。Jasper 还允许 OPTIONS 的解决方法

如果项目是运行在 Tomcat 8 及以上,会发现发出的 PUT 请求和 DELETE 请求可以被控制其接收到,但是返回页面时(forward)会报HTTP 405 的错误提示:"消息 JSP 只允许 GET、POST 或 HEAD。Jasper 还允许 OPTIONS"

解决方案:

  1. 使用 Tomcat 8 以下版本。

  2. 使用 @RestController 或者 @Controller + @ResponseBody 标签,但是这样就无法跳转页面了。

  3. 避免使用 forward 方式跳转页面,改为 重定向redirect方式跳转到另一个控制器方法,再由这个控制器方法跳转页面。

    	@RequestMapping(value = "/rest", method = RequestMethod.PUT)
    	public String put() {
    		// 接收表单中的各种信息
    		System.out.println("PUT --- 更新数据");
    		return "redirect:/success";
    	}
    
    	@RequestMapping(value = "/success")
    	public String success() {
    		return "success";
    	}
    
  4. 给 Tomcat 添加启动参数,使Tomcat允许写操作

    <init-param>
        <param-name>readonly</param-name>
        <param-value>false</param-value>
    </init-param>
    
  5. 创建一个新的 Filter 来过滤 FORWARD

    // HiddenHttpMethodFilter.java
    @Override
    	protected void doFilterInternal(HttpServletRequest request, HttpServletResponse response, FilterChain filterChain)
    			throws ServletException, IOException {
    
    		HttpServletRequest requestToUse = request;
    
    		if ("POST".equals(request.getMethod()) && request.getAttribute(WebUtils.ERROR_EXCEPTION_ATTRIBUTE) == null) {
    			String paramValue = request.getParameter(this.methodParam);
    			if (StringUtils.hasLength(paramValue)) {
    				requestToUse = new HttpMethodRequestWrapper(request, paramValue);
    			}
    		}
    
    		filterChain.doFilter(requestToUse, response);
    	}
    

    HiddenHttpMethodFilter 中的 doFilterInternal 方法是用来过滤 form 表单中 name 为 _method的请求。可以发现,它把请求作为参数传进 HttpMethodRequestWrapper 中并且返回了一个新的请求,放行的也是新的请求。所以我们可以重写 HttpMethodRequestWrapper 中的 getMethod() 方法,让它支持 forward 方式的跳转。

    // 重写 getMethod()
    package com.pudding.conf;
    
    import java.io.IOException;
    
    import javax.servlet.FilterChain;
    import javax.servlet.ServletException;
    import javax.servlet.http.HttpServletRequest;
    import javax.servlet.http.HttpServletRequestWrapper;
    import javax.servlet.http.HttpServletResponse;
    
    import org.springframework.web.filter.HiddenHttpMethodFilter;
    
    public class MyHttpMethodFilter extends HiddenHttpMethodFilter {
    
    	@Override
    	protected void doFilterInternal(HttpServletRequest request, HttpServletResponse response, FilterChain filterChain)
    			throws ServletException, IOException {
    
    		HttpServletRequest requestToUse = request;
    
    		String method = requestToUse.getMethod();
    		if (method.equalsIgnoreCase("delete") || method.equalsIgnoreCase("put")) {
    			method = "POST";
    		}
    
    		requestToUse = new HttpMethodRequestWrapper(request, method);
    
    		filterChain.doFilter(requestToUse, response);
    	}
    
    	private static class HttpMethodRequestWrapper extends HttpServletRequestWrapper {
    
    		private final String method;
    
    		public HttpMethodRequestWrapper(HttpServletRequest request, String method) {
    			super(request);
    			this.method = method;
    		}
    
    		public String getMethod() {
    			return this.method;
    		}
    	}
    }
    

    在 web.xml 中配置自己的过滤器:

    	<filter>
    		<filter-name>myFilter</filter-name>
    		<filter-class>com.pudding.conf.MyHttpMethodFilter</filter-class>
    	</filter>
    	<filter-mapping>
    		<filter-name>myFilter</filter-name>
    		<url-pattern>/*</url-pattern>
    		<dispatcher>FORWARD</dispatcher>
    	</filter-mapping>
    
  6. 在 forward 需要跳转的页面头加上 isErrorPage="true"

    <%@ page language="java" contentType="text/html; charset=UTF-8"
    	pageEncoding="UTF-8" isErrorPage="true"%>
    <!DOCTYPE html>
    <html>
    <head>
    <meta charset="UTF-8">
    <title>Insert title here</title>
    </head>
    <body>
    	<h1>success</h1>
    </body>
    </html>