Re: extends "cannot be resolved to a type"

Oliver Wong wrote:
Did you try compiling the files while ensuring that the current directory be ~ben/docs/comp/lang/java/ ? Did you ensure that "." (the current directory) is part of the CLASSPATH environment variable?

Ben Collver wrote:
Yes to the former, no to the latter. Adding "." to the CLASSPATH environment variable fixes my problem on the Linux box.

My main system has no CLASSPATH environment variable. Since it has no problem, I guess its Java has a built-in class path with "."

Java has no "built-in class path", but your Windows box might.

Generally it is better to script (preferably with Ant) the classpath, invoking the -cp (-classpath) option to the 'java' command, rather than to use the CLASSPATH envar. CLASSPATH is global and inflexible, whereas "-cp" is particular and adaptable.

Also, it is a Bad Thing to use the "default package" for classes.

Better is to use a (possibly fictional) domain, for example "lewscanon.com", invert the top- and second-level domains and add your package name, like this:

com.lewscanon.example.package

which in most filesystems for most class loaders would correspond to the relative path

com/lewscanon/example/package/

in which your Foo class bytecode would appear as

com/lewscanon/example/package/Foo.class

"Relative to what?" you ask? Great question - relative to the first classpath element that has such a subdirectory.

These matters are covered in Sun's tutorial.

-- Lew
.

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