Parsing documents in Java called via JNI

Question

My native application is in C running on WinXP, and I am attempting to call an API in Java using JNI. I am quite a JNI newbie so hopefully someone can shed some light on my issue. Everytime I attempt to parse a document in Java using:
DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
factory.setValidating(true); // also tried false
DocumentBuilder builder = factory.newDocumentBuilder();
builder.setErrorHandler(this);
Document document = builder.parse(new File(filename));I get an IncompatibleClassChangeError exception thrown. This happens when I parse XML, text, you name it. The Java code works fine outside of JNI. The C source snippet (minus the exception checking) looks like the following:
testClass = (*env)->FindClass(env, "TestClass");
testMethod = (*env)->GetMethodID(env, testClass, "test", "(Ljava/lang/String;)I");
filename = (*env)->NewStringUTF(env, "test.xml");
value = (*env)->CallIntMethod(env, testClass, testMethod, filename); Any suggestions would be very much appreciated.

Answer 1

I believe I have found the problem, and it's (of course) an exercise in double-checking everything. It also makes me want to slay my predecessors for their confusing design choices.
The class JNIMessage isn't in the class hierarchy of Message, though it appears to be if you're not inspecting the code closely enough. This is almost certainly the problem. I was looking in the wrong place; the JNI code is probably not suspect here.