Can a class implements more than one interface?

Question

Hello
Can a class implements more than one interface?
Thanks

Answer 1

Of course, this doesn't mean that it won't be a problem though. If the two interfaces have methods with the same signature, but different return types, you won't be able to implement them together. I.E.
interface InterfaceA {
  public int doSomething(String myString);
interface InterfaceB {
  public String doSomething(String myString);
// Now the classes
// Gives error "Duplicate method doSomething(String) in type ClassA"
public class ClassA implements InterfaceA, InterfaceB {
  public int doSomething(String myString) {
    System.out.println("A");
    return 0;
  public String doSomething(String myString) {
    System.out.println("B");
    return 0;
// Gives error "The return type is incompatible with InterfaceB.doSomething(String)"
public class ClassB implements InterfaceA, InterfaceB {
  public int doSomething(String myString) {
    System.out.println("A");
    return 0;
// Gives error "The return type is incompatible with InterfaceA.doSomething(String)"
public class ClassC implements InterfaceA, InterfaceB {
  public String doSomething(String myString) {
    System.out.println("B");
    return 0;
}