UserInput


Java OOP Public

Easy  

15min

User interface contains two types of user input controls: TextInput, which accepts all characters and NumericInput, which accepts only digits.

Implement the class TextInput that contains:

  • Public method void add(char c) - adds the given character to the current value
  • Public method String getValue() - returns the current value

Implement the class NumericInput that:

  • Inherits TextInput
  • Overrides the add method so that each non-numeric character is ignored

For example, the following code should output "10":

TextInput input = new NumericInput();
input.add('1');
input.add('a');
input.add('0');
System.out.println(input.getValue());
   

  •   Example case: java.lang.ClassCastException
  •   Adding various characters to TextInput: java.lang.NoSuchMethodException
  •   Adding numeric characters to NumericInput: java.lang.ClassCastException
  •   Adding various characters to NumericInput: java.lang.ClassCastException