stagesupport/src/main/java/com/streamsets/pipeline/lib/el/MathEL.java
private static Object convertStringToAppropriateNumber(String value) {
    if(value.contains(".")) {
      return Double.valueOf(value);
    } else {
      return Long.valueOf(value);
    }
  }
private static Object convertStringToAppropriateNumber(String value) {
    if(value.contains(".")) {
      return Double.valueOf(value);
    } else {
      return Long.valueOf(value);
    }
  }
We need to support Strings as some information that user might need to deal with is inherently stored in String
variables - for example header values or CSV files.

The way we're processing strings is - if it contains dot, then it's assumed to be a double otherwise long. If we for
whatever reason fail to parse the number and error is thrown.