这是用文本文件作为存储载体的投票系统：
vote.java:
// Java Document
package vote;
import java.io.*;
import java.util.*;
public class vote extends Object
{
public String filePath="";
public int n;
private File voteFile;
private BufferedReader fileRead;
private PrintWriter fileWrite;
public String systemMessage="";
private String voteStr[]=new String[10];
public int voteNum[]=new int[10];
public void createFile()
throws FileNotFoundException
{
voteFile=new File(filePath);
if(!voteFile.exists())
{
fileWrite=new PrintWriter(new FileOutputStream(filePath));
for(int i=0;i<n;i++) fileWrite.println("0");
fileWrite.close();
}
}
public void writeFile()
throws FileNotFoundException
{
fileWrite=new PrintWriter(new FileOutputStream(filePath));
for(int i=0;i<n;i++)
{
fileWrite.println(voteNum[i]);
}
fileWrite.close();
}
public void readFile()
throws FileNotFoundException
{
fileRead=new BufferedReader(new FileReader(filePath));
for(int i=0;i<n;i++)
{
try
{voteStr[i]=fileRead.readLine();
}
catch(IOException f)
{
voteStr[i]="0";}
voteNum[i]=Integer.parseInt(voteStr[i]);
}
try
{
fileRead.close();
}
catch(IOException d)
{
systemMessage=d.toString();
}
}
}
vote.jsp:
<%@ page contentType="text/html; charset=gb2312" language="java" errorPage="" %>
<%@ page import="java.util.*"%>
<%@ page import="java.lang.*"%>
<%@ page import="java.io.*"%>
<jsp:useBean id="vote" scope="request" class="vote.vote"/>
<%
String vote1=request.getParameter("lang");
vote.n=4;
vote.filePath="vote.txt";
vote.createFile();
vote.readFile();
if(vote1.compareTo("0")==0)
vote.voteNum[0]++;
if(vote1.compareTo("1")==0)
vote.voteNum[1]++;
if(vote1.compareTo("2")==0)
vote.voteNum[2]++;
if(vote1.compareTo("3")==0)
vote.voteNum[3]++;
vote.writeFile();
%>
<script language="javascript">
alert("感谢你投了宝贵的一票");
self.location="index.jsp";
</script>
see.jsp:
<%@ page contentType="text/html; charset=gb2312" language="java" errorPage="" %>
<%@ page import="java.util.*"%>
<%@ page import="java.lang.*"%>
<%@ page import="java.io.*"%>
<jsp:useBean id="vote" scope="request" class="vote.vote"/>
<%
String vote1=request.getParameter("lang");
vote.n=4;
vote.filePath="vote.txt";
vote.createFile();
vote.readFile();
int total=0;
float voteFlo[]=new float[5];
for(int i=0;i<4;i++) total+=vote.voteNum[i];
for(int i=0;i<4;i++) voteFlo[i]=150*((float)vote.voteNum[i]/(float)total);
%>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312">
<title>查看调查</title>
<link href="t1.css" rel="stylesheet" type="text/css">
</head>
<body>
<table width="30%" border="0" class="t1">
<tr>
<td colspan="2"><div align="center">调查结果</div></td>
</tr>
<tr>
<td width="18%">JSP</td>
<td width="82%"><img src="bar.gif" width=<%=voteFlo[0]%> height=8> <%=vote.voteNum[0]%></td>
</tr>
<tr>
<td>ASP</td>
<td><img src="bar.gif" width=<%=voteFlo[1]%> height=8> <%=vote.voteNum[1]%></td>
</tr>
<tr>
<td>PHP</td>
<td><img src="bar.gif" width=<%=voteFlo[2]%> height=8> <%=vote.voteNum[2]%></td>
</tr>
<tr>
<td>其他</td>
<td><img src="bar.gif" width=<%=voteFlo[3]%> height=8> <%=vote.voteNum[3]%></td>
</tr>
<tr>
<td colspan="2"><div align="center"><a href="javascript:window.close();">关闭窗口</a></div></td>
</tr>
</table>
</body>
</html>
index.jsp:
<%@ page contentType="text/html; charset=gb2312" language="java" import="java.sql.*" errorPage="" %>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312">
<title>投票</title>
<link href="t1.css" rel="stylesheet" type="text/css">
</head>
<script language="javascript">
function cw()
{window.open("see.jsp","mywindow","toolbar=no,left=150,top=200,width=270,height=350,menubar=no,systemMenu=no");
}
</script>
<body>
<table width="15%" height="250" align="left">
<tr>
<td><form name="form1" method="post" action="vote.jsp">
<table width="100%" height="250" border="1" align="center" bordercolor="#9966CC" class="t1">
<tr>
<td><div align="left">你所使用的开发语言</div></td>
</tr>
<tr>
<td><input type="radio" name="lang" value="0">
JSP</td>
</tr>
<tr>
<td><input type="radio" name="lang" value="1">
ASP</td>
</tr>
<tr>
<td><input type="radio" name="lang" value="2">
PHP</td>
</tr>
<tr>
<td><input type="radio" name="lang" value="3">
其他 </td>
</tr>
<tr>
<td><div align="center">
<input name="vote" type="image" src="poll.gif" width="40" height="20" border="0">
<a href="javascript:cw()"><img src="see.gif" width="40" height="20" border="0"></a></div></td>
</tr>
</table>
</form></td>
</tr>
</table>
</body>
</html>
