Writing to a file using url

Hi all,
I have build an applet which I am going to put in a web. Right now I am working locally and I'm able to read file's using this code:
url = new URL("http://localhost/file.txt");
            is = url.openStream();
            BufferedReader bufRdr = new BufferedReader(new InputStreamReader(is));
            while((line = bufRdr.readLine()) != null)
              //do things
            bufRdr.close();
            is.close();
        }Now I would like to be able to write in this file. How could I do it?
Thanks!

Using HTTP to open a local file will only work if you have a web server running locally, and if that server happens to know how to find and deal with that file.
If you want to use that same web server to write files locally, then your local web server will need to have functionality to write files.
So your first issue is dealing with that. How you do this will depend on what web server you're currently running.
Using a web server might not be the best approach, by the way.

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Writing to a file using log4j

Hi ,
I am facing an issue in rolling out file on an hourly basis. I have a source file , say usagelog_date.log which records logging, then after an hour an hour I have to separate that file , give it a different name say usagelog_date.10.log , I copy the contents of the source file into the rolling file, and make that source file empty. But after making that file empty when I am writing to the file using some threads simultaneously, I get some blank characters first and only after that the logging starts, that increases the file size to a large extent.
My java code which does this separation is as follows.
package com.proquest.services.usage.helper;
import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.FileReader;
import java.nio.channels.FileLock;
import java.util.Calendar;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
public class UsageRotator {
     private Log scpLog = LogFactory.getLog("SCPLog");
     public String rotateAndReturnFilename(String rotationdate, String location) throws Exception {
          Calendar calendar = Calendar.getInstance();
          int hour_of_day = calendar.get(Calendar.HOUR_OF_DAY);
          String rotationalTime = ((hour_of_day < 10) == true) ? "0" + hour_of_day : "" + hour_of_day;
          String rotatedFileName = null;
          File usageLoggingLogFile = new File(location + "usagelogging." + rotationdate + ".log");
          if (usageLoggingLogFile != null && usageLoggingLogFile.exists()) {
               File usageLoggingRotatedFile = new File(location + "usagelogging." + rotationdate + "." + rotationalTime + ".log");
               copyFile(usageLoggingLogFile, usageLoggingRotatedFile);
//copying the contents of source file to a rolling file
               FileOutputStream fout = new FileOutputStream();
// making the source file empty fout.flush();
               usageLoggingLogFile.setWritable(true);
               boolean isEmpty = isFileEmpty(usageLoggingLogFile);
               if(isEmpty)
                    scpLog.info("Existing file has been empty so it's good to proceed for looging next occurances");
               rotatedFileName = usageLoggingRotatedFile.getName();
               scpLog.info("Log file has been rotated to "+rotatedFileName);
          } else {
               throw new Exception("File rotation failed : UsageLogging file couldn't be found for the supplied date");
          return rotatedFileName;
     private void copyFile(File source, File destn) throws Exception {
          FileInputStream fis = new FileInputStream(source);
     FileOutputStream fos = new FileOutputStream(destn);
     try {
     byte[] buf = new byte[1024];
     int i = 0;
     while ((i = fis.read(buf)) != -1) {
     fos.write(buf, 0, i);
     catch (FileNotFoundException e) {
     throw new Exception("[ERROR] File copy failed");
     finally {
     if (fis != null) fis.close();
     if (fos != null) fos.close();
     private boolean isFileEmpty(File file) throws Exception {
          FileReader fr = new FileReader(file);
          BufferedReader br = new BufferedReader(fr);
          boolean isEmpty = true;
          while (br.readLine() != null) {
               isEmpty = false;
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And my log4j file with which I am writing is
# Default is to send information messages and above to the console
log4j.rootLogger = DEBUG, DailyLogFileAppender
# Logger configurations
#log4j.logger.com.proquest.services.usage=DEBUG, DailyLogFileAppender
log4j.logger.com.proquest.services.UsageLog=INFO, UsageLogFileAppender
# Appender configurations
# Define an appender which writes to a file which is rolled over daily
log4j.appender.DailyLogFileAppender = com.proquest.services.log.PqDailyRollingFileAppenderExt
log4j.appender.DailyLogFileAppender.File = logs/usagelogging/usagelogging-error.log
log4j.appender.DailyLogFileAppender.DatePattern = '.'yyyy-MM-dd
log4j.appender.DailyLogFileAppender.Append = true
log4j.appender.DailyLogFileAppender.layout = org.apache.log4j.PatternLayout
log4j.appender.DailyLogFileAppender.layout.ConversionPattern=%d{ISO8601} %m%n
log4j.additivity.com.proquest.services.usage = false
log4j.additivity.com.proquest.services.UsageLog = false
log4j.appender.UsageLogFileAppender = com.proquest.services.log.PqDailyRollingFileAppenderExt
log4j.appender.UsageLogFileAppender.File = logs/usagelogging/usagelogging.log
log4j.appender.UsageLogFileAppender.DatePattern = '.'yyyy-MM-dd
log4j.appender.UsageLogFileAppender.Append = true
log4j.appender.UsageLogFileAppender.layout=org.apache.log4j.PatternLayout
log4j.appender.UsageLogFileAppender.layout.ConversionPattern=%d{ISO8601} %m%n
Can somebody please suggest me what to do, as I have been badly deadlocked into the problem.
Thanks
Suman

neoghy wrote:
... rolling out file on an hourly basis.
And my log4j file with which I am writing is
# Default is to send information messages and above to the console
log4j.rootLogger = DEBUG, DailyLogFileAppender
# Logger configurations
#log4j.logger.com.proquest.services.usage=DEBUG, DailyLogFileAppender
log4j.logger.com.proquest.services.UsageLog=INFO, UsageLogFileAppender
# Appender configurations
# Define an appender which writes to a file which is rolled over daily
log4j.appender.DailyLogFileAppender = com.proquest.services.log.PqDailyRollingFileAppenderExt
log4j.appender.DailyLogFileAppender.File = logs/usagelogging/usagelogging-error.log
log4j.appender.DailyLogFileAppender.DatePattern = '.'yyyy-MM-dd
log4j.appender.DailyLogFileAppender.Append = true
log4j.appender.DailyLogFileAppender.layout = org.apache.log4j.PatternLayout
log4j.appender.DailyLogFileAppender.layout.ConversionPattern=%d{ISO8601} %m%n
log4j.additivity.com.proquest.services.usage = false
log4j.additivity.com.proquest.services.UsageLog = false
log4j.appender.UsageLogFileAppender = com.proquest.services.log.PqDailyRollingFileAppenderExt
log4j.appender.UsageLogFileAppender.File = logs/usagelogging/usagelogging.log
log4j.appender.UsageLogFileAppender.DatePattern = '.'yyyy-MM-dd
log4j.appender.UsageLogFileAppender.Append = true
log4j.appender.UsageLogFileAppender.layout=org.apache.log4j.PatternLayout
log4j.appender.UsageLogFileAppender.layout.ConversionPattern=%d{ISO8601} %m%nCan somebody please suggest me what to do, as I have been badly deadlocked into the problem.I assume you mean [DailyRollingFileAppender ^apache^|http://logging.apache.org/log4j/1.2/apidocs/org/apache/log4j/DailyRollingFileAppender.html]
log4j.appender.DailyRollingFileAppender.DatePattern = '.'yyyy-MM-dd-HH

Writing into a remote file using URL.

     URL url = new URL("http://144.16.241.110:9090/b.txt");
     URLConnection connection = url.openConnection();
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I am using the following code to write into that file.
This is compiled and no error comes while compiling.
But while running I get the following.
<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">
<HTML><HEAD>
<TITLE>405 Method Not Allowed</TITLE>
</HEAD><BODY>
<H1>Method Not Allowed</H1>
The requested method POST is not allowed for the URL /b.txt.<P>
<HR>
<ADDRESS>Apache/1.3.12 Server at 144.16.241.110 Port 9090</ADDRESS>
</BODY></HTML>
How to rectify this.Thanx in advance.
I am able to read from the same file.

Thanx
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Two different methods for downloading a file using URL...

I was just wondering if someone could shed some light on whether I should be downloading files using java.net.URL or java.net.URLConnection
Here are two ways that I have found to work (and yes I realize that one is outputting to a stream and the other is getting put into a StringBuffer):
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Thanks,
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hi,
try out the following code
// Program: copyURL.java
// Author: Anil Hemrajani ([email protected])
// Purpose: Utility for copying files from the Internet to local disk
// Example: 1. java copyURL http://www.patriot.net/users/anil/resume/resume.gif
// 2. java copyURL http://www.ibm.com/index.html abcd.html
import java.net.*;
import java.io.*;
import java.util.Date;
import java.util.StringTokenizer;
class copyURL
public static void main(String args[])
if (args.length < 1)
System.err.println
("usage: java copyURL URL [LocalFile]");
System.exit(1);
try
URL url = new URL(args[0]);
System.out.println("Opening connection to " + args[0] + "...");
URLConnection urlC = url.openConnection();
// Copy resource to local file, use remote file
// if no local file name specified
InputStream is = url.openStream();
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urlC.getContentType());
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date.toLocaleString() + ")...");
System.out.flush();
FileOutputStream fos=null;
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String localFile=null;
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while (st.hasMoreTokens())
localFile=st.nextToken();
fos = new FileOutputStream(localFile);
else
fos = new FileOutputStream(args[1]);
int oneChar, count=0;
while ((oneChar=is.read()) != -1)
fos.write(oneChar);
count++;
is.close();
fos.close();
System.out.println(count + " byte(s) copied");
catch (MalformedURLException e)
{ System.err.println(e.toString()); }
catch (IOException e)
{ System.err.println(e.toString()); }
ok

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Untitled 7.JPG ‏99 KB

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writer.write("<body>" + cadenabody + "</body>");
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Yes, in fact what I want is the file to be in the server, now, I modificated my code to the following:
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import javax.servlet.http.*;
import java.io.*;
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String cadenabody = req.getParameter("mensaje");
String cadenashortcode = req.getParameter("shortcode");
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Writing to remote files using an applet.

I programmed a basic game as an applet for a web site, but it really needs some kind of high score functionality.
I plan to store the high scores in a file in the server. Reading information from the file is no problem at all, but updating the file with new highscores runs into security problems. Obviously I can't simple use a simle file writer to do that. What is the proper way to do this?
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Why not host this applet on another free server which supports mysql/postgresql/etc and store it in a database? Any hosts/tools needed, just ask - there are several good freeware.
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list of all your files in a query format and then compare your
filename against the values in the directory.

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