| /* |
| [The "BSD licence"] |
| Copyright (c) 2005-2008 Terence Parr |
| All rights reserved. |
| |
| Redistribution and use in source and binary forms, with or without |
| modification, are permitted provided that the following conditions |
| are met: |
| 1. Redistributions of source code must retain the above copyright |
| notice, this list of conditions and the following disclaimer. |
| 2. Redistributions in binary form must reproduce the above copyright |
| notice, this list of conditions and the following disclaimer in the |
| documentation and/or other materials provided with the distribution. |
| 3. The name of the author may not be used to endorse or promote products |
| derived from this software without specific prior written permission. |
| |
| THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
| IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
| OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
| IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
| INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
| NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
| THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| package org.eclipse.persistence.internal.libraries.antlr.runtime; |
| |
| /** A source of tokens must provide a sequence of tokens via nextToken() |
| * and also must reveal it's source of characters; CommonToken's text is |
| * computed from a CharStream; it only store indices into the char stream. |
| * |
| * Errors from the lexer are never passed to the parser. Either you want |
| * to keep going or you do not upon token recognition error. If you do not |
| * want to continue lexing then you do not want to continue parsing. Just |
| * throw an exception not under RecognitionException and Java will naturally |
| * toss you all the way out of the recognizers. If you want to continue |
| * lexing then you should not throw an exception to the parser--it has already |
| * requested a token. Keep lexing until you get a valid one. Just report |
| * errors and keep going, looking for a valid token. |
| */ |
| public interface TokenSource { |
| /** Return a Token object from your input stream (usually a CharStream). |
| * Do not fail/return upon lexing error; keep chewing on the characters |
| * until you get a good one; errors are not passed through to the parser. |
| */ |
| public Token nextToken(); |
| |
| /** Where are you getting tokens from? normally the implication will simply |
| * ask lexers input stream. |
| */ |
| public String getSourceName(); |
| } |