Javac error with classpath, but java works

Question

after setting class path, for example, i build a hello.java under c:\dev and i put it in the classpath,
i goto c:\dev\ and typed javac hello.java, then i got hello.class, then i goto d:\
and type java hello, it prints the string correctly, but if i type javac hello.java under d:\, it gave error: cannot read hello.java, but in the classpath, c:\dev is correctly set and commond java can run the hello.class from d:\, so why canot javac do the same.
does that mean i have to go to the directory where the .java file is in to compile?

Answer 1

It's true, class path only helps javac find other classes to include with your class. You must either compile in the source path, specify the source path in the file name or best choice, use ANT.