Question

I have a ‘unsigned char *’ and I want to pass it on to the Java code using JNI
I have tried it in the following way

jstring test1;  
std::string str(reinterpret_cast<const char*>(ucptest));  
test1 = env->NewStringUTF(str.c_str());

where ‘ucptest’ is ‘unsigned char *’ and has ascii values in it.
this code works and I can successfully pass jstring to Java code, but in the load call I am seeing crash in JVM.

What could be the possible reason for the crash? crash is inconsistence, which could mean memory corruption.

Can someone suggest a better way to pass ‘unsigned char*’ to Java?

any help is appreciated.

Thanks

Answer 1

I found the solution, and thought I would share the same, so that others could use it.

Initially I was converting char* to C++ String and then passing it to Java String. This was working just fine, until we had “0” in the string I was trying to convert. This was causing a crash.

Finally, I used a byte array to pass on the value to server. This is working perfectly.

jbyteArray jbArray = env->NewByteArray((int)call.len);
env->SetByteArrayRegion(jbArray, 0, (int)call.len, (jbyte*)call.data);