Cause
This error occurs when an object reference in a guarded expression is not of the type asserted by the type cast. For example, in the JADE language expression object.Automobile, if object is not a member of the class of Automobile (that is, it is not of type Automobile), this error would occur when the expression is evaluated.
Action
Determine why an object reference of the wrong type is being used in this context, and correct the code that led to the error. The method and source position containing the expression at which the exception was raised are reported in the error description.
For more details about type cast expression, see Chapter 1 of the