interface A { public int add(int i, int j); } interface B { public int add(int i, int j, int k); } abstract class C { public int sub(int i, int j) { return j - i; } } class D extends C implements A, B { @Override public int add(int i, int j) { return i + j; } @Override public int add(int i, int j, int k) { return i + j + k; } } public class JavaGenMUB6 { public int mul(int i, int j) { return i * j; } public int mul(int i, int j, int k) { return i * j * k; } public static void main(String[] args) { JavaGenMUB6 obj = new JavaGenMUB6<>(); System.out.println(obj.mul(2, 3)); System.out.println(obj.mul(2, 3, 4)); } }