poll_result.jsp

一个真实的网络选课系统,由实际需求得到的,本人实际开发出来,运用JSP+TOMCAT

<%@ page import="java.util.*,java.lang.*,java.io.*"%>
<%
  String action=request.getParameter("action");
  String vote=request.getParameter("vote");
  String polldata="";
  if (action.compareTo("poll")==0)
    { String resultsDir="C:/Program Files/Apache Software Foundation/Tomcat 5.5/webapps/vote/";
      
      File myfile=new File(resultsDir+System.getProperty("file.separator")
      +"vote.txt");
      if(!(myfile.exists()))
      {
       FileWriter resultsFile=new FileWriter(resultsDir+System.getProperty
      ("file.separator")+"vote.txt",true);
       PrintWriter toFile=new PrintWriter(resultsFile);
       if (vote.compareTo("shopping")==0) polldata="1:0:0";
       if (vote.compareTo("support")==0) polldata="0:1:0";
       if(vote.compareTo("product")==0) polldata="0:0:1";
       toFile.print(polldata);
       resultsFile.close();
      }
      else
      {FileInputStream tfile=new FileInputStream(resultsDir+System.getProperty("file.separator")+"vote.txt");
       String str="";
       int c;
       while ((c=tfile.read())!=-1)
        {str=str+(char)c;
        }
        int first=str.indexOf(":");
        int last=str.lastIndexOf(":");
        int lenth=str.length();
        String First=str.substring(0,first);
        String Next=str.substring(first+1,last);
        String Last=str.substring(last+1,lenth);
        tfile.close();
        Long a1=new Long(First);
        Long a2=new Long(Next);
        Long a3=new Long(Last);
        long b1=a1.longValue();
        long b2=a2.longValue();
        long b3=a3.longValue();
        if (vote.compareTo("shopping")==0) b1=b1+1;
        if (vote.compareTo("support")==0) b2=b2+1;
        if (vote.compareTo("product")==0) b3=b3+1;
        Long c1=new Long(b1);
        Long c2=new Long(b2);
        Long c3=new Long(b3);
        String d1=c1.toString();
        String d2=c2.toString();
        String d3=c3.toString();
        str=d1+":"+d2+":"+d3;
        RandomAccessFile savefile =new RandomAccessFile(resultsDir+
        System.getProperty("file.separator")+"vote.txt","rw");
        savefile.writeBytes(str);
        savefile.close();
      }
      %>
      <script language=javascript>
      alert("Thanks for your voting!");
      self.location="../vote/index.jsp";
      </script>
      <%
      }  
    %>
>