Is there a Java equivalent of GetCompressedFileSize?

Question

I am looking to get accurate (i.e. the real size on disk and not the normal size that includes all the 0\'s) measurements of sparse files in Java.

In C++ on Windows one

Answer 1

If you are doing it on Windows alone, you can write it with Java Native Interface

class NativeInterface{
   public static native long GetCompressedFileSize(String filename);
}

and in C/C++ file:

extern "C"
JNIEXPORT jlong JNICALL Java_NativeInterface_GetCompressedFileSize
  (JNIEnv *env, jobject obj, jstring javaString)
{
    const char *nativeString = env->GetStringUTFChars(javaString, 0);

    char buffer[512];
    strcpy(buffer, nativeString);
    env->ReleaseStringUTFChars(javaString, nativeString);
    return (jlong) GetCompressedFileSize(buffer, NULL);
}