question: public long copy ( final InputStream from , final OutputStream to ) throws IOException { long count = 0 ; byte [ ] tmp = mByteArrayPool . get ( mTempBufSize ) ; try { while ( true ) { int read = from . read ( tmp , 0 , mTempBufSize ) ; if ( read == - 1 ) { return count ; } to . write ( tmp , 0 , read ) ; count += read ; } } finally { mByteArrayPool . release ( tmp ) ; } }
target:  Copy all bytes from InputStream to OutputStream.