Filepath probs running Java w/ DOS and Java 2 SDK

Question

Please help! I have been trying to get a .class file to run for the past four days, using DOS to run the file. I have tried to enter every filepath I can -think- of, and the program still will not run. I have even tried running the file on others' computers that also have a Java 2 SDK...and still cannot get the file to run. However, I know for certain that the file is correct and is able to be run....so that means that somehow I am not putting in the right filepath. I guess my question is....what's the file path?
Here's what I was told to do...which has not worked thus far...
My Java SDK filepath is: C:/Java2SDK1.4.0
I was instructed to open DOS, then, to get to here:
C:\Documents and Settings\Administrator\Desktop>I did so, and as instructed entered the filepath to the javac file inside the java sdk and after it, to put the filename with a .java extension. However, I ONLY have a class file. I don't have the .java file, nor was it ever handed to me.That filepath requested is: C:/Java2SDK1.4.0/bin/javac MathPrac.java
I entered the filepath, so my DOS prompt looked like this before I hit the enter key:
C:\Documents and Settings\Administrator\Desktop>C:/Java2SDK1.4.0/bin/javac MathPrac.javaI hit enter, and it gives me a LONG list of garbage. I even tried reversing the slash marks. Please help? This thing is due Monday and my instructor is refusing to return my emails. I don't want to fail this course due to an instructor being unwilling to assist a student, and a student having tried just about everything she could think of before finally coming here and asking for help.
Would it matter if the SDK for some reason won't recognize my .java files either? I even tried doing the filepath with a file I KNOW should work...and on computers it should have worked on...and could not get it to accept my filepath.
Any help would be very very very highly appreciated. Thanks!

Answer 1

Author: philip_ross
To run a .class file you have to use the java command (javac is the compiler which creates .class files from .java files). Try running
C:\Java2SDK1.4.0\bin\java MathPrac
Thank you for the suggestion, however when I attempted to run it, I got an error that said: Exception in thread "main" java.lang.NoClassDefFoundError: MathPrac
Isn't this an error that states that the name of the file and the class name inside the file are not the same? And if so, how can I check to see if they are the same if I don't have the .java file? I did double-check my spelling, tried it four times just to be sure.
To ChuckBing:
Hey, thanks for the tutorial! I'll take a look at that, too. It always helps to have other resources.
To jwenting:
<Grin>. Duly noted, and thanks. I was trying to keep from being -too- technical in my explanation of what was going on.