Seems couple of things are wrong here. First error tells you that the ATTTestDB class is not in your classpath. Where is this class located?
The last two tell you that "javac" is not recognized which might be that you have not set the PATH environment variable for the bin directory of the JDK installation? Do you have the source of this file to try compiling?
And don't put your/third party class files (or anything for that matter) inside JDK installation; use another directory inside your home directory.