jstring return in JNI program - string

Question

This is JNI code.
Java code:
public class Sample1 {
public native String stringMethod(String text);
public static void main(String[] args)
{
System.loadLibrary("Sample1");
Sample1 sample = new Sample1();
String text = sample.stringMethod("world");
System.out.println("stringMethod: " + text);
}
}
Cpp Method for stringMethod function:
JNIEXPORT jstring JNICALL Java_Sample1_stringMethod
(JNIEnv *env, jobject obj, jstring string) {
const char *name = env->GetStringUTFChars(string, NULL);//Java String to C Style string
char msg[60] = "Hello ";
jstring result;
strcat(msg, name);
env->ReleaseStringUTFChars(string, name);
puts(msg);
result = env->NewStringUTF(msg); // C style string to Java String
return result;
}
When running my java code. I got the result below.
stringMethod: world
But I appended the string "world" with "Hello ". I'm also returning here the appended string. But why I'm getting only "world" not "Hello World". Really I confused with this code. What should I do to get the result with appended string?

Answer 1

JNIEXPORT jstring JNICALL Java_Sample1_stringMethod
(JNIEnv *env, jobject obj, jstring string)
{
const char *name = (*env)->GetStringUTFChars(env,string, NULL);
char msg[60] = "Hello ";
jstring result;
strcat(msg, name);
(*env)->ReleaseStringUTFChars(env,string, name);
puts(msg);
result = (*env)->NewStringUTF(env,msg);
return result;
}

Answer 2

There are several ways but the best I got by converting const char * to c++ string and then to jbyteArray, and its easy to conversion of byteArray to UTF-8 on java side.
C++ side:
const char* string = propertyValue;
std::string str = string;
jbyteArray array = env->NewByteArray(str.length());
env->SetByteArrayRegion(array,0,str.length(),(jbyte*)str.c_str());
return array;
Java/kotlin side:
String((array), Charset.defaultCharset()))