Thread: Trouble running a java file from the windows command prompt.

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I have configured the CLASSPATH and JAVA_HOME environmental variables in windows. Yet I'm not able to run my java file using the command prompt. Please help.

Originally Posted by JavaEnthusiast

...Please help.

Here's the sequence:

javac Example.java

If no errors then

java Example


Cheers!

Z

Apparently it doesn't work.. It says file not found. I've set all the variables. Is there anything els I can do?

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I'm atttaching screenprint of the package and console. I think there's an issue with the commands I'm using. Could someone please review?

Thanks.
Sowmya.

Yes, when I followed the exact steps it worked. Thanks.

Could you please explain to me creating packages for a simple calculation like factorial?

Steps I'm following:

1. Created a dir java_learn/fact.
2. Created two packages algos and test.
3. I've the following java file in algos.

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4. I've the following file in test.

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5. I'm navigating to test package and executing the Example file. Got the following errors.

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Originally Posted by JavaEnthusiast

Yes, when I followed the exact steps it worked...

All I wanted to do was to make sure your installation files and paths were correct. When you changed things and didn't tell me what you changed (like having a package statement) it made it a matter of guesswork.

Originally Posted by JavaEnthusiast

Could you please explain...]

Compile and run Java program in package from command line | Shiva Blog

Java Practices -> Command line operations


Cheers!

Z

package test;

import math.Factorial;

public class TestMe {

public static void main

(String args[]) {


/**Factorial of a num- Main**/

Factorial ex = new

Factorial();


System.out.println("Factorial of 3

is "+ ex.fact(8));


}
}

--------------------------------------------

package math;

public class Factorial{

public int fact(int num){
int result;
if (num==1) return 1;
result = fact(num -1) * num;
return result;
}
}

--------------------------------------------------

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I agree.. I'm sorry for being vague. Could you please check my recent post? I really appreciate your help.

Did you look at the links that I gave? I mean different people have different ways of organizing the projects, and I thought those were pretty representative (and I also thought they gave enough information...)

Oh, well...

Create a brand new empty project directory somewhere convenient.

(For the sanity of anyone whom you might inveigle into helping you in the future, don't create directories or file names with spaces.)

On my Windows XP workstation I have a directory named F:\home\Zaphod.

I'll create a new directory named Project1 in F:\home\Zaphod. You do something appropriate for your system. Create a brand new directory named Project1

Then here's the drill:

Navigate to that directory and create two new directories to hold your source files and create a directory to hold your class tree:


mkdir math
mkdir test
mkdir classes

cd into directory Project1\test
Create a new file named TestMe.java

Paste the following into TestMe.java

//
// File: Project1\test\TestMe.java
//
//  Zaphod_b
//
package test;
 
import math.Factorial;
 
public class TestMe
{
 
    public static void main (String [] args)
    {
        Factorial ex = new Factorial();
 
        int n = 8;
 
        System.out.println("Factorial of " + n + " is " + ex.fact(8));
    }
}

cd into directory Project1\math.
Create a new file named Factorial.java and paste the following into that file:

//
// File Project1\math\Factorial.java
//
// Zaphod_b
//
package math;
 
public class Factorial
{
    public int fact(int num)
    {
        int result;
        if (num < 2)
        {
            return 1;
        }
        result = fact(num - 1) * num;
        return result;
    }
}

Now cd back into Project1

From the Project1 directory, execute the following:

javac -d classes -classpath classes math/Factorial.java

If all went well, there will be a file named Factorial.class in the Projects1\classes\math directory

Then from the Project1 directory, execute:

javac -d classes -classpath classes test/TestMe.java

Now there should be a file named TestMe.class in the Projects1\classes\test directory

Finally: Drum roll please!
From the Project1 directory, execute:

java -classpath classes test.TestMe

My output (taa-daa):

Factorial of 8 is 40320




Cheers!

Z

Hey Z,

Thanks a bunch. It worked like charm.