Return different type of data from a method in java?

Question

public static void main(String args[]) {
    myMethod(); // i am calling static method from main()
 }

.

public static ? myMethod(){         


        

Answer 1

I create various return types using enum. It doesn't defined automatically. That implementation look like factory pattern.

public  enum  SmartReturn {

    IntegerType, DoubleType;

    @SuppressWarnings("unchecked")
    public  T comeback(String value) {
        switch (this) {
            case IntegerType:
                return (T) Integer.valueOf(value);
            case DoubleType:
                return (T) Double.valueOf(value);
            default:
                return null;
        }
    }
}

Unit Test:

public class MultipleReturnTypeTest {

  @Test
  public void returnIntegerOrString() {
     Assert.assertTrue(SmartReturn.IntegerType.comeback("1") instanceof Integer);
     Assert.assertTrue(SmartReturn.DoubleType.comeback("1") instanceof Double);
  }

}