throw

The EGL throw statement specifies an exception that you want to trigger. Doing so has the following effects:

• Program processing ceases
• If the exception is thrown within a try block, control passes to the first appropriate onException block within that try block. For more details, see try.
• If the exception is not thrown within a try block, the program terminates with the message in the specified exception record.

Specify an exception expression (an expression that resolves to the type of an exception variable; see The Exception stereotype) with the throw statement. Here are two forms that such an expression can take:

// when the exception is already defined
nullEx NullValueException;
...
throw nullEx;

// define and declare
Record CustomerException type Exception
  customerNumber INT;
end
...
throw new customerException { 
  customerNumber = custNum,
  message = "Illegal customer number" };