src/main/java/org/helm/notation2/parser/StateMachineParser.java
public boolean checkRepeating(String str) {
    String pattern = "\\d+|\\d+-\\d+";
    if (str.matches(pattern)) {
      return true;
    }
    return false;
  }
public boolean checkRepeating(String str) {
    String pattern = "\\d+|\\d+-\\d+";
    if (str.matches(pattern)) {
      return true;
    }
    return false;
  }
method to validate the repeating section it can be a single number or a
range

@param str repeating information
@return true if the information is valid, false otherwise