Xml 关于servlet异常

web.xml

---

AppExceptionHandler.java

package com.journaldev.servlet.exception;

import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

@WebServlet("/MyExceptionServlet")
public class MyExceptionServlet extends HttpServlet {
    private static final long serialVersionUID = 1L;

    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        throw new ServletException("GET method is not supported.");
    }

}

package com.journaldev.servlet.exception；
导入java.io.IOException；
导入java.io.PrintWriter；
导入javax.servlet.ServletException；
导入javax.servlet.annotation.WebServlet；
导入javax.servlet.http.HttpServlet；
导入javax.servlet.http.HttpServletRequest；
导入javax.servlet.http.HttpServletResponse；
@WebServlet（“/AppExceptionHandler”）
公共类AppExceptionHandler扩展了HttpServlet{
私有静态最终长serialVersionUID=1L；
受保护的无效数据集（HttpServletRequest请求，
HttpServletResponse响应）引发ServletException，IOException{
processError（请求、响应）；
}
受保护的void doPost（HttpServletRequest请求，
HttpServletResponse响应）引发ServletException，IOException{
processError（请求、响应）；
}
private void processError（HttpServletRequest请求，
HttpServletResponse（响应）引发IOException{
//分析servlet异常
Throwable-Throwable=（Throwable）请求
.getAttribute（“javax.servlet.error.exception”）；
整数状态码=（整数）请求
.getAttribute（“javax.servlet.error.status_code”）；
字符串servletName=（字符串）请求
.getAttribute（“javax.servlet.error.servlet_name”）；
if（servletName==null）{
servletName=“未知”；
}
字符串请求URI=（字符串）请求
.getAttribute（“javax.servlet.error.request_uri”）；
if（requestUri==null）{
requestUri=“未知”；
}
//设置响应内容类型
response.setContentType（“text/html”）；
PrintWriter out=response.getWriter（）；
填写（“例外/错误详细信息”）；
如果（状态代码！=500）{
输出。写入（“错误详细信息”）；
输出。写入（“状态代码”：“+statusCode+”
”；
out.write（“请求的URI：”+requestUri）；
}
其他的
{
填写（“例外情况详情”）；
out.写出（“
Servlet名称：“+servletName+”
”）；
out.write（“
异常名称：“+throwable.getClass（）.getName（）+”
”；
out.write（“
请求的URI:+requestUri+”
”；
out.write（“
异常消息：“+throwable.getMessage（）+”
”；
写出“
”；
}
写出（“

”）；
请写出（“”）；
请写出（“”）；
}
}

1） 我面临的问题是，我没有进入Servlet AppExceptionHandler中的processError方法，因此我无法在前端看到异常

---

因此，请告诉我是哪里出错的。

它在您的服务器日志中显示任何异常吗？不，它在服务器日志中没有显示任何异常。此外，我仍然收到404 not error found，但对于该异常，应调用未调用的异常。请帮助任何人解决我的问题？？？？？大家好，请关于Servlet中的异常帮助我解决问题

package com.journaldev.servlet.exception;

import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

@WebServlet("/MyExceptionServlet")
public class MyExceptionServlet extends HttpServlet {
    private static final long serialVersionUID = 1L;

    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        throw new ServletException("GET method is not supported.");
    }

}

package com.journaldev.servlet.exception;

import java.io.IOException;
import java.io.PrintWriter;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

@WebServlet("/AppExceptionHandler")
public class AppExceptionHandler extends HttpServlet {
    private static final long serialVersionUID = 1L;

    protected void doGet(HttpServletRequest request,
            HttpServletResponse response) throws ServletException, IOException {
        processError(request, response);
    }

    protected void doPost(HttpServletRequest request,
            HttpServletResponse response) throws ServletException, IOException {
        processError(request, response);
    }

    private void processError(HttpServletRequest request,
            HttpServletResponse response) throws IOException {
        // Analyze the servlet exception
        Throwable throwable = (Throwable) request
                .getAttribute("javax.servlet.error.exception");
        Integer statusCode = (Integer) request
                .getAttribute("javax.servlet.error.status_code");
        String servletName = (String) request
                .getAttribute("javax.servlet.error.servlet_name");
        if (servletName == null) {
            servletName = "Unknown";
        }
        String requestUri = (String) request
                .getAttribute("javax.servlet.error.request_uri");
        if (requestUri == null) {
            requestUri = "Unknown";
        }

        // Set response content type
          response.setContentType("text/html");

          PrintWriter out = response.getWriter();
          out.write("<html><head><title>Exception/Error Details</title></head><body>");
          if(statusCode != 500){
              out.write("<h3>Error Details</h3>");
              out.write("<strong>Status Code</strong>:"+statusCode+"<br>");
              out.write("<strong>Requested URI</strong>:"+requestUri);
          }
          else
          {
              out.write("<h3>Exception Details</h3>");
              out.write("<ul><li>Servlet Name:"+servletName+"</li>");
              out.write("<li>Exception Name:"+throwable.getClass().getName()+"</li>");
              out.write("<li>Requested URI:"+requestUri+"</li>");
              out.write("<li>Exception Message:"+throwable.getMessage()+"</li>");
              out.write("</ul>");
          }

          out.write("<br><br>");
          out.write("<a href=\"index.html\">Home Page</a>");
          out.write("</body></html>");
    }
}