Java HotSpot Virtual Machine

hi,

1.. I have created the Cpp file to implemement the native method but it seems that the native method can not complie rightly , it tells me follows

error C2819: type 'JNIEnv_' does not have an overloaded member 'operator ->'
c:\program files\microsoft visual studio\vc98\include\jni.h(764) : see declaration of 'JNIEnv_'
c:\users\wangyue\desktop\java_gui\beattrack 5.6 - ������_������_������������ 5.7\beattrack.cpp(202) : error C2227: left of '->GetByteArrayRegion' must point to class/struct/union

then I use the c file to paste the same code, it can complie rightly , why? I really need my native method to complie rightly in Cpp file, how to solve it?

2.I want to return a double, for the most simple way, I do the following

#include "RealBeatTrack_BeatTrack.h"

JNIEXPORT jdoubleArray JNICALL Java_playaudio_BeatTrack_BeatTrack
(JNIEnv *env, jobject j, jbyteArray data)
{


jdouble outdata[4]={1,2,3,4};

return (*env)->NewDoubleArray(env, outdata);
}

then in the java code, I difine a array to receive it,

say double mydata[] = new double[4];

mydata= BeatTrack(buffedata);


but the java comlier tells me the Exception in thread "Thread-2" java.lang.OutOfMemoryError: Java heap space?
anyone can help me?


Thanks