动态JSP页生成静态HTML的方法

本文实例讲述了动态jsp页生成静态html的方法。分享给大家供大家参考。具体如下：

具体实现：

利用filter的过滤功能把*.jsp过滤出来，判断是否存在对应的.html文件，如果不存在对应的.html文件，则将其内容读出写入指定的.html文件，再跳转到对应的.html即可。如果存在对应的.html文件，则直接跳转到对应的.html即可。
 
代码：

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 自动生成方法存根
  }
  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 自动生成方法存根
  }
}

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();
    //----获取请求的url
    string reqtarget = request.getparameter("name");
    //----指定对应jsp的html名称
    string name = reqtarget.substring(reqtarget.lastindexof("/") + 1,reqtarget.lastindexof("."));
    //---判断是否存在对应的html文件
    file file = new file(request.getrealpath("/") + name + ".html");
    if (!file.exists()) {  //--------如果不存在对应的html文件
      try {
        file.createnewfile();  //--------创建html文件
        //-------将jsp的内容写入对应的html文件内
        inputstream in;
        stringbuffer sb = new stringbuffer("");
      //----注意这里，不能直接访问请求的url，如果直接访问的话，会陷入死循环
        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();
        //---------------转到与jsp对应的html页
        response.sendredirect(request.getcontextpath()+"/"+name + ".html");
      } catch (exception e) {
        e.printstacktrace();
      }
    }else{
      //----------如果存在指定的html，直接跳转到指定的html页
      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配置：

<?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>

希望本文所述对大家的jsp程序设计有所帮助。