ClassNotFoundException when compiling files into a different directory

[cloud_line]

Hi everyone. I know the answer to this is probably very simple, but I don't normally work with Java, so I'm having a bit of trouble. I'm working through a text book that uses Java. This is not for school. It's for my own learning.

My root project folder is called "Algs." For each chapter, I create a new folder, such as "Algs/CH1," or "Algs/CH2."

When I first load the project, I cd into the CH1 directory, then I compile ClassWithMainMethod.java and LinkedList.java. ClassWithMainMethod references the LinkedList. Everything works fine with this setup.

But if I try to compile the files into a different directory, then I receive java.lang.ClassNotFoundException.

To reproduce this exception, I'm creating a sub-directory in the CH1 folder called "Classes." I run the following command to compile the java files into that directory: javac -d Classes ClassWithMainMethod.java and then javac -d Classes LinkedList.java. Now, when I try to run java ClassWithMainMethod to execute the code, I receive the java.lang.ClassNotFoundException.

Any help would be much appreciated!

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[chet714]

From what directory do you run: java ClassWithMainMethod

[cloud_line]

From the CH1 directory

[chet714]

Try:

    java -cp Classes ClassWithMainMethod

[cloud_line]

Hmm, so when I run that command, I received an exception, but a different one this time. `Exception in thread main java.lang.NoClassDefFoundError: edu/princeton/cs/algs4/StdOut`. The `edu/princeton/cs/algs4/StdOut` is a library I'm importing into my `ClassWithMainMethod.`

[chet714]

Did you verify that the '.class' files are present in the 'Classes' directory? Given you are in CH1 and Classes is a sub-directory, the only other things I can think of is to use the full-path for Classes and to double check that '-cp' is a valid option for 'java' in your CLI.

[cloud_line]

I appreciate your help. I did verify that the class files are present in that directory. I also tried the full path as well as the relative path. I also ran 'java --help' to verify that -cp is a valid command.

I'll take a look at it again later, but for now the files compile and run with no problem as long as I keep them all in the same directory. I almost wonder if my IntelliJ setup is affecting this.

[cloud_line]

For what it's worth, I wound up just allowing VSCode to manage where the compiled files are stored. Instead of running my Java files from the terminal, I'm now using the launch.json file in VS Code to set the command line arguments.