Class NewExpression


  • public class NewExpression
    extends Expression
    Expression which implements a new operation.
    • Method Detail

      • bind

        public void bind()
                  throws TypeException
        verify that variables mentioned in this expression are actually available in the supplied bindings list
        Specified by:
        bind in class Expression
        Throws:
        TypeException - if any variable is missing or has the wrong type
      • typeCheck

        public Type typeCheck​(Type expected)
                       throws TypeException
        ensure that all type references in the expression and its component expressions can be resolved, that the type of the expression is well-defined and that it is compatible with the type expected in the context in which it occurs.
        Specified by:
        typeCheck in class Expression
        Parameters:
        expected - the type expected for the expression in the contxt in which it occurs. this may be void but shoudl not be undefined at the point where type checking is performed.
        Returns:
        the expression type
        Throws:
        TypeException - if type checking fails
      • getCandidateArgClass

        public Class getCandidateArgClass​(List<Constructor> candidates,
                                          int argIdx)
      • interpret

        public Object interpret​(HelperAdapter helper)
                         throws ExecuteException
        evaluate the expression by interpreting the expression tree
        Specified by:
        interpret in class Expression
        Parameters:
        helper - an execution context associated with the rule whcih contains a map of current bindings for rule variables and another map of their declared types both of which are indexed by varoable name. This includes entries for the helper (name "-1"), the recipient if the trigger method is not static (name "0") and the trigger method arguments (names "1", ...)
        Returns:
        the result of evaluation as an Object
        Throws:
        ExecuteException - if an error occurs during execution