protected void checkValidity(int ordinal) throws InvalidDataTypeException {
		checkValidity();
		if (ordinal < 0 || ordinal >= getCount()) {
			throw new IllegalArgumentException(ordinal + " is not a valid ordinal for " +
				getName() + " data type at " + getAddress() + " in " + getProgram() + ".");
		}
	}
This method can be called by a model's methods to validate the model before trying 
to retrieve a particular piece of information. It also validates that the ordinal value 
doesn't exceed the count for the model.
<br>Important: This method must not be called by any methods that are called (possibly 
indirectly) by the model's validateModelSpecificInfo() method.
@param ordinal the ordinal indicating which one of the multiple copies of the data type
to be laid down at the address.
@throws InvalidDataTypeException if the model's data type isn't valid at the associated
address in the program.
Ghidra/Features/MicrosoftCodeAnalyzer/src/main/java/ghidra/app/cmd/data/AbstractCreateDataTypeModel.java