question: public boolean readHeader ( RandomAccessFile raf ) throws IOException { StringBuffer id = new StringBuffer ( 4 ) ; for ( int i = 0 ; i < 4 ; i ++ ) { int ch = raf . read ( ) ; if ( ch < 32 ) { String hx = Integer . toHexString ( ch ) ; if ( hx . length ( ) < 2 ) { hx = "0" + hx ; } return false ; } id . append ( ( char ) ch ) ; } _chunkID = id . toString ( ) ; _size = AiffUtil . readUINT32 ( raf ) ; return true ; }
target:  Reads the header of a chunk.  If _chunkID is non-null, it's assumed to have already been read.