Android isn’t Java. It uses the Java language, and compiles (in part) with the Java compiler, but the runtime isn’t Java, and it has a different runtime library than Java (although many libraries can be compiled as-is for use in Android.)
Android, therefore, is not Java. If you have a question that’s related to pure Java – meaning that it’s source-code related, and doesn’t use the Android libraries, and doesn’t rely on the Android runtime characteristics – you can probably get an answer in ##java.
On the other hand, if your question is related to user interfaces at all – as in, stuff that you see, hear, or read, or interact with – it’s likely to be specific to Android. Don’t be surprised if you get help that relies on features that are unique to Java (i.e., that rely on features in Java 7 or Java 8) — and don’t complain about it if you do.
The bottom line: you might be able to get pure-Java help in ##java. You’re probably best off taking Android questions to #android-dev.