Method of generating static HTML from dynamic JSP page

This paper illustrates the method of generating static HTML from dynamic JSP page. Share it for your reference. The details are as follows:

Concrete realization:

Use the filtering function of Filter to filter *. jsp, and judge whether there is a corresponding. html file. If there is no corresponding. html file, read its contents into the specified. html file, and then jump to the corresponding. html. If there is a corresponding. html file, jump directly to the corresponding. html.

Code:

JspFilter. java:

import java.io.BufferedReader;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.HttpURLConnection;
import java.net.URL;
import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class JspFilter implements Filter {
  public void destroy() {
    // TODO  Automatically generate method stubs 
  }
  public void doFilter(ServletRequest request, ServletResponse response,
      FilterChain chain) throws IOException, ServletException {
    HttpServletRequest hreq = (HttpServletRequest) request;
    HttpServletResponse hresp = (HttpServletResponse) response;
    String name = hreq.getRequestURL().substring(
          hreq.getRequestURL().lastIndexOf("/") + 1,
          hreq.getRequestURL().lastIndexOf("."));
    if (hreq.getRequestURL().indexOf(".jsp") != -1 && (null == hreq.getParameter("type") || hreq.getParameter("type").equals(""))) {
        hresp.sendRedirect(hreq.getContextPath()+"/conversion?name="+hreq.getRequestURL());
        return ;
    }
    chain.doFilter(request, response);
  }
  public void init(FilterConfig arg0) throws ServletException {
    // TODO  Automatically generate method stubs 
  }
}

ConversionServlet. java:

import java.io.BufferedReader;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.HttpURLConnection;
import java.net.URL;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class ConversionServlet extends HttpServlet {
  public ConversionServlet () {
    super();
  }
  public void destroy() {
    super.destroy(); // Just puts "destroy" string in log
    // Put your code here
  }
  public void doGet(HttpServletRequest request, HttpServletResponse response)
      throws ServletException, IOException {
    response.setContentType("text/html");
    PrintWriter out = response.getWriter();
    //---- Object of the request URL
    String reqTarget = request.getParameter("name");
    //---- Specify the corresponding JSP Adj. HTML Name 
    String name = reqTarget.substring(reqTarget.lastIndexOf("/") + 1,reqTarget.lastIndexOf("."));
    //--- Judge whether there is a corresponding HTML Documents 
    File file = new File(request.getRealPath("/") + name + ".html");
    if (!file.exists()) {  //-------- If there is no corresponding HTML Documents 
      try {
        file.createNewFile();  //-------- Create HTML Documents 
        //------- Will JSP Writes the contents of the corresponding HTML Within the document 
        InputStream in;
        StringBuffer sb = new StringBuffer("");
      //---- Note here that you cannot directly access the requested URL If accessed directly, it will fall into an infinite loop 
        URL url = new java.net.URL(reqTarget.toString()+"?type=11");
        HttpURLConnection connection = (HttpURLConnection) url
            .openConnection();
        connection.setRequestProperty("User-Agent", "Mozilla/4.0");
        connection.connect();
        in = connection.getInputStream();
        java.io.BufferedReader breader = new BufferedReader(
            new InputStreamReader(in, "GBK"));
        String currentLine;
        FileOutputStream fos = new FileOutputStream(file);
        while ((currentLine = breader.readLine()) != null) {
          sb.append(currentLine);
          fos.write(currentLine.getBytes());
        }
        if (null != breader)
          breader.close();
        if (null != fos)
          fos.close();
        //--------------- Go to the same as JSP Corresponding HTML Page 
        response.sendRedirect(request.getContextPath()+"/"+name + ".html");
      } catch (Exception e) {
        e.printStackTrace();
      }
    }else{
      //---------- If the specified HTML That jumps directly to the specified HTML Page 
      response.sendRedirect(request.getContextPath()+"/"+name + ".html");
    }
  }
  public void doPost(HttpServletRequest request, HttpServletResponse response)
      throws ServletException, IOException {
    doGet(request, response);
  }
  public void init() throws ServletException {
    // Put your code here
  }
}

WEB. XML configuration:

<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.4"
  xmlns="http://java.sun.com/xml/ns/j2ee"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee
  http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">
 <filter>
  <filter-name>jspfilter</filter-name>
  <filter-class>com.beanutil.JspFilter</filter-class>
 </filter>
 <filter-mapping>
  <filter-name>jspfilter</filter-name>
  <url-pattern>*.jsp</url-pattern>
 </filter-mapping>
 <servlet>
  <servlet-name>conversion</servlet-name>
  <servlet-class>com.beanutil.ConversionServlet </servlet-class>
 </servlet>
 <servlet-mapping>
  <servlet-name>conversion</servlet-name>
  <url-pattern>/conversion</url-pattern>
 </servlet-mapping>
</web-app>

I hope this article is helpful to everyone's JSP programming.