Jni: Can Not Get Array Length

I faced with the next problem: I can not do anything with byte[] (jbyteArray) in C code. All functions that work with array in JNI cause JNI DETECTED ERROR IN APPLICATION: jarray a

Solution 1:

The second argument passed to your function isn't a jbyteArray.

Per the JNI documentation, the arguments passed to a native function are:

Native Method Arguments

The JNI interface pointer is the first argument to native methods. The JNI interface pointer is of type JNIEnv. The second argument differs depending on whether the native method is static or nonstatic. The second argument to a nonstatic native method is a reference to the object. The second argument to a static native method is a reference to its Java class.

The remaining arguments correspond to regular Java method arguments. The native method call passes its result back to the calling routine via the return value.

Your jstring convertToHex(JNIEnv* env, jbyteArray array) is missing the second jclass or jobject argument, so you're treating either a jobject or jclass argument and a jbyteArray.

Solution 2:

Your native method signature is incorrect. It should be

static jstring convertToHe(JNIEnv *env, jobject thiz, jbytearray array)