question: private Sound generateSound ( SoundPool soundPool , File dir , String name , int lengthMsec , int freqHz ) { Sound sound = null ; File outFile = new File ( dir , name + ".wav" ) ; if ( ! outFile . exists ( ) ) { try { FileOutputStream fos = new FileOutputStream ( outFile ) ; int sampleCount = lengthMsec * SAMPLE_RATE / 1000 ; ByteBuffer buf = generateWavHeader ( sampleCount ) ; byte [ ] array = buf . array ( ) ; fos . write ( array ) ; buf = generateWavData ( sampleCount , freqHz ) ; array = buf . array ( ) ; fos . write ( array ) ; fos . close ( ) ; Log . d ( TAG , "Wrote sound file " + outFile . toString ( ) ) ; } catch ( IOException ioe ) { Log . e ( TAG , "sound file op failed: " + ioe . getMessage ( ) ) ; throw new RuntimeException ( ioe ) ; } } else { } int handle = soundPool . load ( outFile . toString ( ) , 1 ) ; return new Sound ( name , soundPool , handle ) ; }
target:  Generate a sound with specific characteristics.