Question

My Java classes organization has gotten a little messy so I’m going over something I’ve skipped in my Java learning: the classpath. I can’t quiet get beloved classes to compile in the packages I have created for them. Here’s my folder hierarchy:

.
com/
    david/
        Greet.java

        greeter/
            SayHello.java
            SayGoodbye.java

Where SayHello’s constructor just prints “hello” and SayGoodbye’s prints “Goodbye” and Greet’s main method just creates those two objects. At the top of SayHello is package com.david.greeter; and likewise with SayGoodbye and Greet’s is package com.david;

In the greeter folder I was able to compile both java files but if I go to the current directory (the directory that holds com) and do javac -cp “com.david.greeter.*” com/david/Greet.java it says it can’t find the classes as well as saying package com.david.greeter doesn’t exist. I’ve also tried setting the $CLASSPATH manually.

I’m at my wit’s end here, Stackoverflow (as I normally am when I post here). Do any of you know what I am doing wrong?

Answer 1

The java compiler will traverse the sub-directories of the classpath looking for the packages it needs.

So, your command line should be as follows:

javac -cp "." com/david/Greet.java

When the compiler sees a reference to com.david.greeter.SayHello while compiling Greet.java it will start with the directory in the classpath and traverse the hierarchy looking for the package it needs.