public class RationalMatrix extends GenericMatrix<Rational> { @Override /** Add two rational numbers */ protected Rational add(Rational r1, Rational r2) { return r1.add(r2); } @Override /** Multiply two rational numbers */ protected Rational multiply(Rational r1, Rational r2) { return r1.multiply(r2); } @Override /** Specify zero for a Rational number */ protected Rational zero() { return new Rational(0, 1); } }