[BRLTTY] BRLTTY Java bindings -- UnsatisfiedLinkError

[Mario Lang]

Simon Meers <drmeers at gmail.com> writes:

> Hmm, apparently I spoke too soon -- the Java code connects fine, but as soon
> as you try to do anything with the connection it crashes!

I at least found where it crashes, and how to tell jvm to be a bit
more verbose about the error.  In C terms, it crashes during
the GET_ID macro, in the line

  if (!((id) = (*(jenv))->GetFieldID((jenv), (class), (field), (sig)))) {\

If you invoke java with -Xcheck:jni, suddenly the JVM is a lot
more friendly about the actual error:

fzidpc73:/tmp# java -Xcheck:jni -Djava.library.path=/usr/lib/jni -classpath .:/usr/share/java/brlapi.jar test
FATAL ERROR in native method: Instance field not found in JNI get/set field operations
        at org.a11y.BrlAPI.Native.openConnection(Native Method)
        at org.a11y.BrlAPI.Brlapi.<init>(Brlapi.java:28)
        at test.main(test.java:5)
Aborted

However, this error now seems to happen in openConnection, not
getDriverName.  Something with GET_ID is very broken, but
I am not familiar enough with JNI programming to spot the error.

Maybe someone else could take a look?  Who wrote this code?

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