java.io.File.getCanonicalFile throwing SecurityException

Tue, 13 May 2008 02:27:10 MDT

Hi there Guys,

I'm just being preemptive here, cos you know how things work in dev, and then you move it into test, and things that were always working on your machine stop working. ;-)

I was wondering, Why, or rather, under which conditions would a SecurityException be thrown when calling getCanonicalFile, or getCanonicalPath from the File class. Currently I am doing this in dev, and it's working no probs. I am just wondering why this would happen, and if it does happen, what I can do to stop this from happening.

The java doc says... "If a required system property value cannot be accessed, or if a security manager exists and its java.lang.SecurityManager#checkRead method denies read access to the file"

problem while printing international characters using system.out.print

Mon, 12 May 2008 11:39:08 MDT

Hi All,

I am reading a txt file which contains latin + japanese characters.
I am using inputstreamreader (with encoding mentioned as utf-8) to read the content into a string. Then I printing the string using System.out.println(String). But i only see something like ????? as output.

I think my program only displays those charcters properly which as per system's default encoding.

How can I fix this?

Need to find executable from path

Mon, 12 May 2008 08:27:07 MDT

Hi all,

My application allows the user to specify an executable to be launched on request. This is working ok when the user specifies the complete path to the executable, but I now have an additional requirement: if the complete path is not specified, find the executable in the system PATH.

I'm not finding anything in the APIs that lets me do that, though it seems like it should be a pretty straightforward thing to do: any suggestions?

My current code finds the file on the client system and if it doesn't already exist, tries to download it automatically, like so:

File exec = new File(this.executable).getCanonicalFile();
if(logger.isDebugEnabled())
{
log...

Japanese character set

Mon, 12 May 2008 06:45:07 MDT

What are the problems one may encounter while using Japanese character set. How can they be solved.

I came to know that Japanese character set is a 2 byte character set. Will it have any effect on my application which we intend to develop in Japanese.

Magic behind the serializable interface

Sun, 11 May 2008 06:55:04 MDT

I was trying to understand the concept behind the java serialization.

I know that java serialization is required when you want to save state of an object outside JVM. My thinking was that why dont Sun make all classes as Serializable by default? Why serialization is required to persist an object?

Read more
http://venkatsadasivam.wordpress.com/2008/01/27/what-is-the-magic-serializable-interface-does-in-java/ (http://venkatsadasivam.wordpress.com/2008/01/27/what-is-the-magic-serializable-interface-does-in-java/)

Converting feedfile to utf8 format

Fri, 9 May 2008 05:00:58 MDT

hi all...i have got utf8 format feed file from the providers. i have edited the feedfile using the java code to delete the dtd content and add some tags to the feedfile. after doing this through java code i am getting junk characters in to feedfile.
what should i do to rectify this?

How to I write objects into a gzip file?

Thu, 8 May 2008 19:42:57 MDT

Hi all,

Can somebody help me to find a way to write objects into a gzip file? I've tried ObjectOutputStream and GZIPOutputStream, it doesn't work me. An example would be really helpful.

Cheers,

code output

Mon, 5 May 2008 19:10:48 MDT

Hey guys, I've been looking at the following website for some good I/O examples.

http://www.cafeaulait.org/books/javaio2/ (http://www.cafeaulait.org/books/javaio2/)

Here is the code:

code:


import java.io.*;
 
public class StreamPrinter {
 
 public static void main(String[] args) {
 
 try {
 while (true) {
 int datum = System.in.read();
 if (datum == -1) break;
 System.out.println(datum);
 }
 }
 catch (IOException ex) {
 System.err.println("Couldn't read from System.in!");
 }
 }
}

When I run this program ...

Creating a text file using FileWriter

Mon, 5 May 2008 04:32:46 MDT

I have created a text file using FileWriter.
I can see it properly when i open it with MS-Word,but when i try to open it with notepad or wordpad.
It is not displayed properly.
To print this file, which docflavor should i use?
Whether it is docflavor.INPUT_STREAM.TEXT_PLAIN or wat???

IO close() method

Sat, 3 May 2008 14:44:32 MDT

What exactly does the close() method do for input and output streams? Please use as little jargon as possible.

I am using Apache POI HSSF to read in an Excel file (this maybe should be on an Apache POI forum, but please tell me what you think). I am trying to figure out when I can close the input stream.

If I read in a file containing objects, (any type), close the file input stream, then read in more objects from the associated object input stream, what happens?

Thanks,

Andy

searching a content in a file

Fri, 2 May 2008 03:32:27 MDT

Hi All,

suppose,there are(example D drive) some files which are having paragraph ...

if i give some word in search button..then i submit..now i want the file/files which is having the particular word...

how to do it?

please anyone can explain me

thanks & regards,
seetharaman

how to read a line and store the data!

Fri, 2 May 2008 03:08:27 MDT

For example, the input text file is like this:

KWAFZRMYC 195.08 s 400 0
EDWWKTMYC 195.09 s 400 0
JSQPPHMYC 195.05 s 200 0
LQHTFMMYC 194.95 b 600 1
BTQFADMYC b 500 1
ZOOKNLMYC 195.07 b 400 1
TVZKDZMYC 195.01 b 300 1

First of all, how to read read this file line by line?

After read the file, I need to store them line by line and seperate by space, what data structure recommend, linked list?

Thanks in advance!

security restrictions of file I/O?

Thu, 1 May 2008 21:20:26 MDT

Making a java desktop app that will be deployed in a jar file to multiple operating systems. I want to write a file to disk so that after the user shuts the app down and then later fires it back up again I can then read the file back in from the disk. Seems like this was troublesome years ago because the security api required certain settings in order to give the app access to the disk. I'm just asking a general question because I won't be able to do extensive testing on various hardware and op systems - is it still the case? that security can get in the way of file I/O? Do I need to be concerned about this?

Retrieving images from a folder

Wed, 30 Apr 2008 05:58:22 MDT

Hi Guys,
I'm trying out a program which requires accessing of the images from a folder, and i'm not so familiar with files. Can you show me how???
Thanks a ton

Gettting Error!!

Tue, 29 Apr 2008 05:36:18 MDT

I am using following code to transfer one file to other system:

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.URL;
import java.net.URLConnection;
import java.text.SimpleDateFormat;
import java.util.StringTokenizer;
import java.util.*;
import sun.net.TelnetInputStream;
import sun.net.ftp.FtpClient;
import sun.net.www.protocol.http.HttpURLConnection;
import java.io.*;

public class FtpToServer extends FtpClient
{
public static int BUFFER_SIZE = 10240;
private static FtpClient m_client;
privat...

Writing Big Vector to file.

Tue, 29 Apr 2008 02:22:18 MDT

Dear Friends,
I have one input text file with size around 800MB, which contains the capital word letters and small letter words. I am reading the text file and capturing all the capital letter words in to vector(obvioiusly size of this vector is big, let us assume 700MB).

now my problem is if i want to remove the dupicates in vector and i need to sort the vector, it is going to delay.. delay.... due to vast size.
it is taking so much time to process. if i try with small file eveything is ok!!!

for example ,if it is successful, i need to write this big size vector into flat file.
but this process is taking so much time to do that.
so please suggest the best way to do my scenario.

thanks...

write into a file?

Mon, 28 Apr 2008 05:52:15 MDT

How to write into a file under linux environment? The file is going to be written under /home/testing/temp
with a file as "newFile.txt"
How do I proceed?

how to convert a Bytearray input stream to String

Sun, 27 Apr 2008 00:04:11 MDT

Hi, I have to convert a ByteArryinputString to a string and then decode the string to ByteArrayInputStream.

here is the code i am using to convert the Byte array input stream to String.

generatedInputStream is of type ByteArrayInputStream:

if(generatedInputStream != null){
byte[] buffer = new byte[generatedInputStream.available()];
int bytesRead;
try {
bytesRead = generatedInputStream.read(buffer);
while (bytesRead >= 0)
{
generatedOutputStream.write(buffer, 0, bytesRead);
bytesRead = generatedInputStream.read(buffer);
}
} catch (IOException e) {
// TODO Auto-generated catch block
throw new SSPApplicationException();
}
}
if(ge...

splitting string into 2 variable

Sat, 26 Apr 2008 12:30:09 MDT

i manage to read a textfile with my program which is a string that looks like this: stuck in a hole in the backyard;60173317358
i want to save stuck in a hole in the backyard in variable x and 60173317358 in variable y. can anyone tell me how to do this? thanks in advance

Reading file that is updated while reading

Sat, 26 Apr 2008 03:10:08 MDT

I am reading a file that is being updated by another app while the reader is reading. I read to the end, then go to sleep for a couple of seconds, then look for new data. I am using BufferedReader in a while loop, and readLine() to get the data. Is there a way to read to the end of the file, then wait until the reader 'wakes up' when something new is there, rather than having to sleep?

logging byte[]

Fri, 25 Apr 2008 08:58:06 MDT

Hello, I have a document object that returns a byte[] when I do getContents(), I want to log the contents of this byte[](this has post script data in it) to our log file. How do I it?

Junk value when converting .doc t .txt file

Fri, 25 Apr 2008 03:26:05 MDT

import java.io.*;
class try2
{
public static void main(String[] args)

{
try
{
java.io.File file = new File("C:/read1.doc");
FileInputStream fis = new FileInputStream(file);
byte bytes[] = new byte[fis.available()];
fis.read(bytes);
fis.close();
System.out.println("Hello World! "+bytes.length);

FileOutputStream fis1=new FileOutputStream("C:/read2.txt");
fis1.write(bytes);
fis1.close();
}
catch(Exception e)
{
System.out.println(e);
}
}
}

i am converting doc file to txt file.The file is getting created.The value...

Why a file not picked up?

Thu, 24 Apr 2008 09:36:03 MDT

Hi,All
I run into a strange problem.
My thread (continuous running) keeps scanning files under 90 folders. It will call another program to process the file if there is any new coming file. It works very well except one situation: the thread doesn't recognize a file when the file is in the process of transfering (or copying). That's understandable because this new file is in use by another source. However the thread still is not able to sense thie file even in next runs. But it can find other files as long as that situation (described as above) doesn't happen to these files.
Any comments? Thanks a lot for your help.
Y.P

Polling for a file on ftp using Java

Thu, 24 Apr 2008 06:46:02 MDT

hi,

I have a file on my ftp server. I have to check if any file exists in the ftp directory, for every interval of 5 seconds.Could any one let me know, what is the best way to do it(file polling for every 5 secs) through java ?

quick question: bufferedreader

Thu, 24 Apr 2008 04:46:02 MDT

if you read() a character in the buffer, how do you check for end of line? is it null. just need to make sure. thanks.

nikita

Limit character read using Reader?

Wed, 23 Apr 2008 11:20:00 MDT

Hi
I have to read a Clob from oracle, and using Reader API to read. I want to limit amount of character to read because some of them are huge, and when it render to the browser it stop .The following code that I have is read the whole thing, How do i set the limit of character on this
Many thanks in advance

code:


public String getClobToString()
{
StringBuffer stf = new StringBuffer();
Clob myclob = obj.getClob()--> this get from database
Reader reader = myclob.getCharacterStream(); --> reading the clob
int charread = 0;
char[] buffer = new char[1024];
while ((charread < r.read(buffer)) !=-1)
{
 stf.append(buffer, 0, charread);
 r.close()...

NotSerializableException when i use rmiregistry

Wed, 23 Apr 2008 04:55:59 MDT

I am working with Blaze Rule Engine and reading the binary rules file from the service code that is written in Java. I have to use some classes (located in jars) which supports my application and all the classes are serialized.

after deploying my application as ejb in Oracle Apps, i can use 'rmiregistry' for generating the response.

so, my application is working perfectly fine without rmiregistry and also giving the proper response........ but when i am using the rmiregistry its giving the following error

code:


 
com.blazesoft.server.base.NdServiceException: Service 'TestPro
ject'. Server 'TestProject' on host 'bnk02cpu000693'.
 Error getting Serialize...

how to read a text file within remote ftp directory

Wed, 23 Apr 2008 01:09:59 MDT
Dear friends
How to read a text file within remote ftp directory?
My program is this.I have a directory named "Sample Files" on remote ftp server which contains a text file batch2.txt.I want to read that file.Please tell me how to do it.Here is my program:
/*
* Main.java
*
* Created on April 23, 2008, 4:41 AM
*
* To change this template, choose Tools | Template Manager
* and open the template in the editor.
*/

package javaapplication1;
import com.jscape.inet.ftp.*;
import java.io.BufferedReader;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.util.D...

how to get the last modified time of a text file

Tue, 22 Apr 2008 18:31:47 MDT
How to read the last modified time of a text file or a directory in hh:mm:ss format.

i want to read a file which has been created by Star Office

Tue, 22 Apr 2008 04:12:24 MDT
I have created file by OpenOffice .org and i want to read the content of the file through the program.i am able to read text file and .doc file
what is the difference between office tools and star office and how i should read the file that has created by openoffice.
Please can any one help me

Fast indexing / searching of a text file

Mon, 21 Apr 2008 09:20:17 MDT
Hi : I am writing programs that read data from massive text files.
What is the best way to do this in java ? Is indexing a possibility and if so what is the way to jump from one index to another ? Thanks, Jay

How to write at the end of text file

Sat, 19 Apr 2008 09:22:24 MDT
Hi,

Every time it is overwritting. rather than adding next line of records.
public void WriteToFile(){

try{

FileWriter writer = new FileWriter ("record.txt");

writer.append(v +"\t");
writer.append(u +"\t");
writer.append(x );

writer.close();
}catch(IOException ex){
ex.printStacktrace();
}
}

Fast Access in Binary Files

Fri, 18 Apr 2008 13:48:22 MDT
Hello everyone,
I've never dealt with binary files at all, so I'm just looking for a place to get started (and to find out if I'm even barking up the wrong tree).

Hypothetical (*simplified*) example...
Let's say that starting at 00:00 on 4/18/08, I will start recording the number of users accessing at a web site once every minute. I need to store this data for long term retrieval, and I need very fast access to it to answer questions like.. "How many visitors were there at each minute interval between 5/1/08 08:30 and 5/5/08 15:05?".

I cannot use a database for a number of reasons, but mainly because it will be too much data for a standard rdbms in our environment (billion+ rows). Remember, the above exam...

Serialization & data retrieval

Fri, 18 Apr 2008 13:34:21 MDT
Hello. I have written a program that saves JTextField values to a .ser file. As long as the program is still running, I can read those values back into eaxh JTextField. If I close the program, re-open it, and try to read them in again, the JTextFields remain blank. Am I doing something wrong?

Thanks!

BufferedImage to File Object

Fri, 18 Apr 2008 11:34:21 MDT
Hello!

I have a BufferedImage/Byte Array and i need to create a file object out of it, however I must not write the data to a file and then read it into a file ....

So basically I am trying to convert a BufferedImage which is dynamically generated to a instance of File.

Is there a way to do this?

Thanks guys!

Re-Reading from the stream...

Wed, 16 Apr 2008 16:07:02 MDT
Hi all,

Streams are behaving funny!!! i'll try to give you a gist of the problem instead of just blindly copy pasting the code...

I have,
BufferedReader in = new BufferedReader(new InputStreamReader(socket.getInputStream()));
DataInputStream in_raw = new DataInputStream(socket.getInputStream());

Somewhere in the code, in a while ( true ) loop i do this:-
while ( true ) {
String line = in.readLine();
if ( line.equals("aabbcc") )
break;
}

again; below i have another while ( true ) loop:-
while ( true ) {
for ( .. ; .. ; .. ) {
curr_byte = (byte)in_raw.read();
if ( curr_byte == -1 )
break;<...

Re-Reading from the stream...

Wed, 16 Apr 2008 16:01:02 MDT
Hi all,

Streams are behaving funny!!! i'll try to give you a gist of the problem instead of just blindly copy pasting the code...

I have,
BufferedReader in = new BufferedReader(new InputStreamReader(socket.getInputStream()));
DataInputStream in_raw = new DataInputStream(socket.getInputStream());

Somewhere in the code, in a while ( true ) loop i do this:-
while ( true ) {
String line = in.readLine();
if ( line.equals("aabbcc") )
break;
}

again; below i have another while ( true ) loop:-
while ( true ) {
for ( .. ; .. ; .. ) {
curr_byte = (byte)in_raw.read();
if ( curr_byte == -1 )
break;<...

get content of html

Wed, 16 Apr 2008 12:43:01 MDT
Hi there,

I need to get The content of a site (that I know how to do).

The problem is that I first have to send some parameters to validade, then send another url which will get the url I want to get, it's like this:

http://www3.sitedomain.com/csp/web1/validate.csp?Loggin=1512800710&Pass=21ta93&EP=PAC&LCL=SL (http://www3.sitedomain.com/csp/web1/validate.csp?Loggin=1512800710&Pass=21ta93&EP=PAC&LCL=SL)

Loggin, Pass, EP and SL are the parameters to the first url. then I Have to enter:

http://www3.sitedomain.com/csp/web1/display.csp?LIS=1 (http://www3.sitedomain.com/csp/web1/display.csp?LIS=1)

LIS is the parameter to the url. after entering these two url I will have the ht...

EOF comes in different places

Wed, 16 Apr 2008 11:55:01 MDT
Hello,

I'm reading a file a byte at a time (always the same) and sometimes I read with no problem, other times it gives me an EOF in different executions of the loop.
Can anyone give me a hint why this erratic behavior happens?

Here is the code:
code:

public byte[] readFromFile(String fileName) throws ClientException {
byte[] result = null;
long len;
File file = new File(fileName);
if (utils.testFile(file)) {
len = file.length();
result = new byte[(int)len];
FileInputStream fis;
try {
fis = new FileInputStream(fileName);
} catch (FileNotFoundException fnfe) {
// This should never happen
String errMessage = "File �" + fileN...

EOF comes in different places

Wed, 16 Apr 2008 11:47:01 MDT
Hello,

I'm reading a file a byte at a time (always the same) and sometimes I read with no problem, other times it gives me an EOF in different executions of the loop.
Can anyone give me a hint why this erratic behavior happens?

Here is the code:
code:

public byte[] readFromFile(String fileName) throws ClientException {
byte[] result = null;
long len;
File file = new File(fileName);
if (utils.testFile(file)) {
len = file.length();
result = new byte[(int)len];
FileInputStream fis;
try {
fis = new FileInputStream(fileName);
} catch (FileNotFoundException fnfe) {
// This should never happen
String errMessage = "File �" + fileN...

EOF comes in different places

Wed, 16 Apr 2008 11:15:01 MDT
Hello,

I'm reading a file a byte at a time (always the same) and sometimes I read with no problem, other times it gives me an EOF in different executions of the loop.
Can anyone give me a hint why this erratic behavior happens?

Here is the code:
code:

public byte[] readFromFile(String fileName) throws ClientException {
byte[] result = null;
long len;
File file = new File(fileName);
if (utils.testFile(file)) {
len = file.length();
result = new byte[(int)len];
FileInputStream fis;
try {
fis = new FileInputStream(fileName);
} catch (FileNotFoundException fnfe) {
// This should never happen
String errMessage = "File �" + fileN...

EOF comes in different places

Wed, 16 Apr 2008 11:13:01 MDT
Hello,

I'm reading a file a byte at a time (always the same) and sometimes I read with no problem, other times it gives me an EOF in different executions of the loop.
Can anyone give me a hint why this erratic behavior happens?

Here is the code:
code:

public byte[] readFromFile(String fileName) throws ClientException {
byte[] result = null;
long len;
File file = new File(fileName);
if (utils.testFile(file)) {
len = file.length();
result = new byte[(int)len];
FileInputStream fis;
try {
fis = new FileInputStream(fileName);
} catch (FileNotFoundException fnfe) {
// This should never happen
String errMessage = "File �" + fileN...

EOF comes in different places

Wed, 16 Apr 2008 11:05:01 MDT
Hello,

I'm reading a file a byte at a time (always the same) and sometimes I read with no problem, other times it gives me an EOF in different executions of the loop.
Can anyone give me a hint why this erratic behavior happens?

Here is the code:
code:

public byte[] readFromFile(String fileName) throws ClientException {
byte[] result = null;
long len;
File file = new File(fileName);
if (utils.testFile(file)) {
len = file.length();
result = new byte[(int)len];
FileInputStream fis;
try {
fis = new FileInputStream(fileName);
} catch (FileNotFoundException fnfe) {
// This should never happen
String errMessage = "File �" + fileN...

EOF comes in different places

Wed, 16 Apr 2008 10:41:01 MDT
Hello,

I'm reading a file a byte at a time (always the same) and sometimes I read with no problem, other times it gives me an EOF in different executions of the loop.
Can anyone give me a hint why this erratic behavior happens?

Here is the code:
code:

public byte[] readFromFile(String fileName) throws ClientException {
byte[] result = null;
long len;
File file = new File(fileName);
if (utils.testFile(file)) {
len = file.length();
result = new byte[(int)len];
FileInputStream fis;
try {
fis = new FileInputStream(fileName);
} catch (FileNotFoundException fnfe) {
// This should never happen
String errMessage = "File �" + fileN...

JavaRanch I/O and Streams

code throws error "java.io.EOFException"?

change path

DVD Burning

change path

Accessing files on a server

Reading postgresql.conf file using java

java.io.File.getCanonicalFile throwing SecurityException

problem while printing international characters using system.out.print

Need to find executable from path

Japanese character set

Magic behind the serializable interface

Converting feedfile to utf8 format

How to I write objects into a gzip file?

code output

Creating a text file using FileWriter

IO close() method

searching a content in a file

how to read a line and store the data!

security restrictions of file I/O?

Retrieving images from a folder

Gettting Error!!

Writing Big Vector to file.

write into a file?

how to convert a Bytearray input stream to String

splitting string into 2 variable

Reading file that is updated while reading

logging byte[]

Junk value when converting .doc t .txt file

Why a file not picked up?

Polling for a file on ftp using Java

quick question: bufferedreader

Limit character read using Reader?

NotSerializableException when i use rmiregistry

how to read a text file within remote ftp directory

how to get the last modified time of a text file

i want to read a file which has been created by Star Office

Fast indexing / searching of a text file

How to write at the end of text file

Fast Access in Binary Files

Serialization & data retrieval

BufferedImage to File Object

Re-Reading from the stream...

Re-Reading from the stream...

get content of html

EOF comes in different places

EOF comes in different places

EOF comes in different places

EOF comes in different places

EOF comes in different places

EOF comes in different places