question: public int readInt ( ) throws IOException { length += 4 ; int k1 = in . read ( ) ; if ( k1 < 0 ) return 0 ; int k2 = in . read ( ) << 8 ; int k3 = in . read ( ) << 16 ; return k1 + k2 + k3 + ( in . read ( ) << 24 ) ; }
target:  Read the next int from the InputStream.