Java – must be called ReleaseStringUTFChars after GetStringUTFChars (when char * is passed to C function)?

I'm a little confused about the objects passed from Java to C? Should they be deleted in native JNI methods or garbage collected when the method returns For example:

If I have a native declaration public native printstring (string MSG) in my java file; And the native method uses const char * message = (jni_env) – > getstringutfchars (MSG, & iscopy); Gets an array of C - style strings I call (jni_env) – > releasestringutfchars (MSG, message); After doing everything in the native way If so, why is it necessary? Why doesn't the Java runtime environment represent programmers doing this? After declaring all strings and passing them from the Java environment

Solution

The get characters function holds characters in memory until the release method is called Java cannot garbage collect or otherwise move this data until it is determined that no one is using it

Once the Java VM leaves the Java virtual machine, it cannot know the memory usage time, so it needs to manually notify that the memory has been completed