trouble creating jar file

[Mike Harris]

I keep getting a "Can't find main class. Program will exit".

This is what I have:

Copy.java has been compiled to copy.class. Here is the source code:

import java.io.*;
 
 
public class Copy {
 
   public static void main(String[] args) throws IOException {
      File inputFile = new File("text.txt");
      File outputFile = new File("outagain.txt");
 
      FileReader in = new FileReader(inputFile);
      FileWriter out = new FileWriter(outputFile);
      int c;
 
      while ((c = in.read()) != -1)
         out.write(c);
 
      in.close();
      out.close();
   }
}

I wrote a custom manifest file that has these lines of code:

Manifest-version: 1.0
Main-Class: Copy
Created-By: 1.4.2_09 (Sun Microsystems Inc.)

I used windows command line to compile, using this:
jar cmf c:\Manifest.mf c:\Copy.jar C:\Copy.class

Please help!

[Layne Lund]

When do you get that error? Does it happen when you run the jar program to create the jar file or when you try to run the program after you created the jar file?

Layne

[Mike Harris]

I get the error after I have created the jar file and I try to execute the .jar

[Jesper de Jong]

> jar cmf c:\Manifest.mf c:\Copy.jar C:\Copy.class

Try this:

jar cmf c:\Copy.jar c:\Manifest.mf C:\Copy.class

(the name of the JAR file first, then the manifest file).

How are you trying to run your JAR? I guess with this:

java -jar Copy.jar

[Layne Lund]

Once you create a jar file, run the following command:

jar tf Copy.jar

This will show the contents of the jar file so you can verify that it contains the files you expect.

Also, we need to know how you execute the jar file? Do you use the command that Jesper gave above?

Layne