This Android sample shows how to handle exceptions across the JNI boundary.
Native exceptions can be caught in JNI methods and re-thrown in the JVM. Because
uncaught native exceptions will cause your app to crash, we recommend catching
all exceptions as a fail-safe. You may also want to catch instances of
std::exception or your own exception interface:
extern "C" JNIEXPORT void JNICALL
Java_com_example_exceptions_MainActivity_throwsException(JNIEnv* env,
jobject /* this */) {
try {
might_throw();
} catch (std::exception& e) {
jniThrowRuntimeException(env, e.what());
} catch (...) {
jniThrowRuntimeException(env, "Catch-all");
}
}Then, you can do the same in your Java/Kotlin code:
try {
jniMethodThatMightThrow();
} catch (e: java.lang.RuntimeException) {
// Handle exception
}The hard part here is using the JNI API to throw an exception in the JVM. That
is, implementing jniThrowRuntimeException. We recommend referring to
JNIHelp.h
and
JNIHelp.c
in the Android platform's libnativehelper, from which
exception_helper.h and
exception_helper.cpp are
adapted.
If you've found an error in these samples, please file an issue.
Patches are encouraged, and may be submitted by forking this project and submitting a pull request through GitHub. Please see CONTRIBUTING.md for more details.
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http://www.apache.org/licenses/LICENSE-2.0
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