public void checkOclConstraint(
     String expression,
     NamedElement context,
     Type requiredType,
     boolean isCollection,
     boolean isUnique,
     boolean isOrdered)
     throws SemanticException {
   try {
     oclEnvironment.analyseOclExpression(
         expression, context, requiredType, isCollection, isUnique, isOrdered);
   } catch (OclException ex) {
     throw new SemanticException("Ocl error: " + ex.getMessage());
   }
 }