예제 #1
0
        public override string GetErrorMessage(RecognitionException e, string[] tokenNames)
        {
            string msg = null;

            if (e is MismatchedTokenException)
            {
                MismatchedTokenException mte = (MismatchedTokenException)e;
                msg = "mismatched character " + GetCharErrorDisplay(e.Character) + " expecting " + GetCharErrorDisplay(mte.Expecting);
            }
            else if (e is NoViableAltException)
            {
                NoViableAltException nvae = (NoViableAltException)e;
                // for development, can add "decision=<<"+nvae.grammarDecisionDescription+">>"
                // and "(decision="+nvae.decisionNumber+") and
                // "state "+nvae.stateNumber
                msg = "no viable alternative at character " + GetCharErrorDisplay(e.Character);
            }
            else if (e is EarlyExitException)
            {
                EarlyExitException eee = (EarlyExitException)e;
                // for development, can add "(decision="+eee.decisionNumber+")"
                msg = "required (...)+ loop did not match anything at character " + GetCharErrorDisplay(e.Character);
            }
            else if (e is MismatchedNotSetException)
            {
                MismatchedNotSetException mse = (MismatchedNotSetException)e;
                msg = "mismatched character " + GetCharErrorDisplay(e.Character) + " expecting set " + mse.Expecting;
            }
            else if (e is MismatchedSetException)
            {
                MismatchedSetException mse = (MismatchedSetException)e;
                msg = "mismatched character " + GetCharErrorDisplay(e.Character) + " expecting set " + mse.Expecting;
            }
            else if (e is MismatchedRangeException)
            {
                MismatchedRangeException mre = (MismatchedRangeException)e;
                msg = "mismatched character " + GetCharErrorDisplay(e.Character) + " expecting set " +
                      GetCharErrorDisplay(mre.A) + ".." + GetCharErrorDisplay(mre.B);
            }
            else
            {
                msg = base.GetErrorMessage(e, tokenNames);
            }
            return(msg);
        }
예제 #2
0
        /** <summary>What error message should be generated for the various exception types?</summary>
         *
         *  <remarks>
         *  Not very object-oriented code, but I like having all error message
         *  generation within one method rather than spread among all of the
         *  exception classes. This also makes it much easier for the exception
         *  handling because the exception classes do not have to have pointers back
         *  to this object to access utility routines and so on. Also, changing
         *  the message for an exception type would be difficult because you
         *  would have to subclassing exception, but then somehow get ANTLR
         *  to make those kinds of exception objects instead of the default.
         *  This looks weird, but trust me--it makes the most sense in terms
         *  of flexibility.
         *
         *  For grammar debugging, you will want to override this to add
         *  more information such as the stack frame with
         *  getRuleInvocationStack(e, this.getClass().getName()) and,
         *  for no viable alts, the decision description and state etc...
         *
         *  Override this to change the message generated for one or more
         *  exception types.
         *  </remarks>
         */
        public virtual string GetErrorMessage(RecognitionException e, string[] tokenNames)
        {
            string msg = e.Message;

            if (e is UnwantedTokenException)
            {
                UnwantedTokenException ute = (UnwantedTokenException)e;
                string tokenName           = "<unknown>";
                if (ute.Expecting == TokenTypes.EndOfFile)
                {
                    tokenName = "EndOfFile";
                }
                else
                {
                    tokenName = tokenNames[ute.Expecting];
                }
                msg = "extraneous input " + GetTokenErrorDisplay(ute.UnexpectedToken) +
                      " expecting " + tokenName;
            }
            else if (e is MissingTokenException)
            {
                MissingTokenException mte = (MissingTokenException)e;
                string tokenName          = "<unknown>";
                if (mte.Expecting == TokenTypes.EndOfFile)
                {
                    tokenName = "EndOfFile";
                }
                else
                {
                    tokenName = tokenNames[mte.Expecting];
                }
                msg = "missing " + tokenName + " at " + GetTokenErrorDisplay(e.Token);
            }
            else if (e is MismatchedTokenException)
            {
                MismatchedTokenException mte = (MismatchedTokenException)e;
                string tokenName             = "<unknown>";
                if (mte.Expecting == TokenTypes.EndOfFile)
                {
                    tokenName = "EndOfFile";
                }
                else
                {
                    tokenName = tokenNames[mte.Expecting];
                }
                msg = "mismatched input " + GetTokenErrorDisplay(e.Token) +
                      " expecting " + tokenName;
            }
            else if (e is MismatchedTreeNodeException)
            {
                MismatchedTreeNodeException mtne = (MismatchedTreeNodeException)e;
                string tokenName = "<unknown>";
                if (mtne.Expecting == TokenTypes.EndOfFile)
                {
                    tokenName = "EndOfFile";
                }
                else
                {
                    tokenName = tokenNames[mtne.Expecting];
                }
                // workaround for a .NET framework bug (NullReferenceException)
                string nodeText = (mtne.Node != null) ? mtne.Node.ToString() ?? string.Empty : string.Empty;
                msg = "mismatched tree node: " + nodeText + " expecting " + tokenName;
            }
            else if (e is NoViableAltException)
            {
                //NoViableAltException nvae = (NoViableAltException)e;
                // for development, can add "decision=<<"+nvae.grammarDecisionDescription+">>"
                // and "(decision="+nvae.decisionNumber+") and
                // "state "+nvae.stateNumber
                msg = "no viable alternative at input " + GetTokenErrorDisplay(e.Token);
            }
            else if (e is EarlyExitException)
            {
                //EarlyExitException eee = (EarlyExitException)e;
                // for development, can add "(decision="+eee.decisionNumber+")"
                msg = "required (...)+ loop did not match anything at input " +
                      GetTokenErrorDisplay(e.Token);
            }
            else if (e is MismatchedSetException)
            {
                MismatchedSetException mse = (MismatchedSetException)e;
                msg = "mismatched input " + GetTokenErrorDisplay(e.Token) +
                      " expecting set " + mse.Expecting;
            }
            else if (e is MismatchedNotSetException)
            {
                MismatchedNotSetException mse = (MismatchedNotSetException)e;
                msg = "mismatched input " + GetTokenErrorDisplay(e.Token) +
                      " expecting set " + mse.Expecting;
            }
            else if (e is FailedPredicateException)
            {
                FailedPredicateException fpe = (FailedPredicateException)e;
                msg = "rule " + fpe.RuleName + " failed predicate: {" +
                      fpe.PredicateText + "}?";
            }
            return(msg);
        }