You can't access the existing AHP "stuff" from Java. Java runs in a JVM and is pretty "sandboxed". If you were dead set on a tie between the two, you'd have to write some C/C++ code to access the AHP "stuff" then wrap that C/C++ code with JNI so you could call it from Java.
What other's have done is just gone all Java - and they communicate directly with the CM15A or CM11A.
That's not an easy road to take but others have done a lot of work for you.
Jesse Petersen (sp?) comes to mind as an author of some great Java code to access the CM11A/CM15A.