Text and image files within jar files

[erhart]

Hi all,
I am new to using jar files, and I am having a problem accessing files within the jar file. I packaged the jar file using Eclipse. The error that I get is:

java.io.FileNotFoundException: Coordinates.txt <The system cannot find the file specified>
at java.io.FileInputStream.open<Native Method>
at java.io.FileInputStream.<init><Unknown Source>
at java.util.Scanner.<init><Unknown Source>

I can fix this problem by copying and pasting the contents of my files (.txt and .gif) into completely new files and replacing the old ones using WinRAR. When I do this, the program runs perfectly. Unfortunately, when I email my program as an attachment or on some computers when I transfer it with a thumb drive, I get the same error message. Because of the patched-up fix that I found, I am wondering if this could be a problem with file permissions?

Thanks a lot!

[roots]

Please include the code you used to access those files in jar archive. You use Class.getResourceAsStream..

[erhart]

For text files, I use:

Code:

private Scanner openFileForReading(String fileName)
	{
		try{
			scanner = new Scanner (new File(fileName));		
		}
		catch (FileNotFoundException e){
			System.out.println( "Could not open " +
					fileName);
			e.printStackTrace();
		}
		return scanner;
	}

For image files, I use:

Code:

        private Image getCelebrityImage(String fileName){
    		BufferedImage img = null;
    		try {
    			img = ImageIO.read(new File(fileName));
    		} 
    		catch (IOException e) {
    			System.out.println("Unable to access image " + fileName);
    			e.printStackTrace();
    		}
    		return img;
        }

[afsina]

The files in jar files are treated as "Resources". you need to access them as a classpath resource, regular File access methods does not work there. However, it is very easy. check the javadoc of "Class.getREsourceAsStream()". So, what you need is:
- the location-name of the resource in the jar (you will need to add a "/" symbol when writing the name.)
- How will you get the Class? try finding this out first
- This is suppose to return a strem. you already have the code for Scanner or BufferedImage. check their constructors if any accepts an inputstream..
write again if there is a problem.

[erhart]

Thanks a lot for the help! This solves almost all the problems. One question, though: I also want to write to some text files. A PrintWriter constructer takes an OutputStream, but I'm not sure how to get one as a Resource. Does anyone know how to do that?

[erhart]

Never mind, I found a way:

PrintWriter p = new PrintWriter(new File(getClass().getResource(fileName).toURI()));

I really appreciate the help!

[jagadeesh0014]

This tutorial is more help to me tnk u

[jagadeesh0014]

Hi
my name is jagadeesh
q: How to run jsp in tomcat
I need step by step in Image viewing
Tnk u

[jagadeesh0014]

Hi All iam new in server side programs so i need u r help to run jsp and ejb , structs
Tnk u