Create Wave.java

1) _samples [] array is now 2-dimensional: 
double [] [] _samples;
_samples = new double [2] [(int) nSamples];

2) 2 audio channels are read at a time from stereo WAV-file:   
for (i=0; i < nSamples; i++) {
  int sample1 = ( _wave[44+i*(2*i_numofChannels) ] & 0xff) | (short) (_wave[44+i*(2*i_numofChannels)+1] << 8);
 _samples [0] [i]= (double)sample1/(1<<15);
		
 int sample2 = ( _wave[44+i*(2*i_numofChannels)+ 2 ] & 0xff) | (short) (_wave[44+i*(2*i_numofChannels)+3] << 8);
 _samples [1] [i]= (double)sample2/(1<<15);

}