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jsp文件操作之读取篇(本站文章)
转载请注明来源
来源 jsp中国论坛 http://jspbbs.yeah.net
read.jsp
<html>
<head>
<title>read a file</title>
</head>
<body bgcolor="#000000">
<jsp:usebean id="reader" class="delimiteddatafile" scope="request">
<jsp:setproperty name="reader" property="path" value="/path/to/afile.txt" />
</jsp:usebean>
<h3>contents of the file:</h3>
<p>
<% int count = 0; %>
<% while (reader.nextrecord() != -1) { %>
<% count++; %>
<b>line <% out.print(count); %>:</b> <% out.print(reader.returnrecord()); %><br>
<% } %>
</p>
</body>
</html>
import java.io.*;
import java.util.stringtokenizer;
public class delimiteddatafile
{
/**
* delimiteddatafile.java
* written by morgan catlin email: mfcatlin@csclub2.stthomas.edu
* april 6, 1999
*
* variables:
* string currentrecord = the record the bean is currently working on
* bufferedreader file = the file the bean is working with
* string path = the path to the file (ie. /home/you/afile.txt)
* stringtokenizer token = the currentrecord tokenized
*
* methods:
* public void setpath() – creates a bufferedreader that reads the file in path
* public string getpath() – returns path
* public void fileclose() – closes the file that is being read
* public int nextrecord() – reads the next record(line) in the file,
* and returns the number of tokens in the record
* or else returns -1 if there arent anymore records
* public double returndouble() – returns the next token as a double
* public int returnint() – returns the next token as an int
* public string returnstring() – returns the next token as a string
* public string returnrecord() – returns the entire record as a string
*/
private string currentrecord = null;
private bufferedreader file;
private string path;
private stringtokenizer token;
public delimiteddatafile()
{
file = new bufferedreader(new inputstreamreader(system.in),1);
} // constructor 1
public delimiteddatafile(string filepath) throws filenotfoundexception
{
// gets file
path = filepath;
file = new bufferedreader(new filereader(path));
} // constructor delimiteddatafile
public void setpath(string filepath)
{
// sets the file
path = filepath;
try {
file = new bufferedreader(new
filereader(path));
} catch (filenotfoundexception e) {
system.out.println("file not found");
}
} // method setpath
public string getpath() {
return path;
} // method getpath
public void fileclose() throws ioexception
{
// closes file
file.close();
} // method fileclose
public int nextrecord()
{
// this method reads the next record and returns the number of
// tokens or else returns -1
int returnint = -1;
try
{
currentrecord = file.readline();
} // end try
catch (ioexception e)
{
system.out.println("readline problem, terminating.");
} // end catch
if (currentrecord == null)
returnint = -1;
else
{
token = new stringtokenizer(currentrecord);
returnint = token.counttokens();
} // end else
return returnint;
} // method nextrecord
public double returndouble()
{
// this method returns the next token as a double
double doublereturn = double.valueof(token.nexttoken()).doublevalue();
return doublereturn;
} // method returndouble
public int returnint()
{
// this method returns the next token as an int
int returnint = integer.parseint(token.nexttoken());
return returnint;
} // method returnint
public string returnstring()
{
// this method returns the next token as a string
string stringreturn = token.nexttoken();
return stringreturn;
} // method returnstring
public string returnrecord()
{
// this method returna the entire record as a string
return currentrecord;
} // method returnrecord
} // class delimiteddatafile
转载请注明来源
来源 jsp中国论坛 http://jspbbs.yeah.net
