class with package / directory tree

[Pin Ting]

Dear all ranchers,
Let's say test.class belongs to package domain1.domain2. (That is, the first line of test.java is "package domain1.domain2;")
Now I would like to execute test.class. Is it necessary to place test.class in the folder "[any_other_folder]\domain1\domain2" and then execute "java domain1.domain2.test" under [any_other_folder]?
Is there a way to execute the class without building the directory tree corresponding to the class' package hierarchy?
Thanks.

[Dirk Schreckmann]

Is there a way to execute the class without building the directory tree corresponding to the class' package hierarchy?
No. Note that the directory structure and class file could be packaged in a JAR file, which is then included in the CLASSPATH setting.
Is it necessary to place test.class in the folder "[any_other_folder]\domain1\domain2" and then execute "java domain1.domain2.test" under [any_other_folder]?
Not exactly. As previously mentioned, the class file and directory structures could be in a JAR file. All that is necessary, is that the base of the directory structure is somehow included in the CLASSPATH setting, then the class can be used from anywhere.

[Stan James]

So far as I know your directory structure must match your package structure when using Sun compiler & JVM, and probably most others.
Visual Age breaks the rules by keeping all source and classes in a repository instead of a file structure, but they have their own JVM and I'm guesing that's how they break the rules.

[Pin Ting]

Thanks, Dirk.
Now I got a very clear picture .