| /* |
| * [The "BSD license"] |
| * Copyright (c) 2010 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.antlr.analysis; |
| |
| import org.antlr.tool.Grammar; |
| import org.antlr.tool.GrammarAST; |
| |
| public class PredicateLabel extends Label { |
| /** A tree of semantic predicates from the grammar AST if label==SEMPRED. |
| * In the NFA, labels will always be exactly one predicate, but the DFA |
| * may have to combine a bunch of them as it collects predicates from |
| * multiple NFA configurations into a single DFA state. |
| */ |
| protected SemanticContext semanticContext; |
| |
| /** Make a semantic predicate label */ |
| public PredicateLabel(GrammarAST predicateASTNode) { |
| super(SEMPRED); |
| this.semanticContext = new SemanticContext.Predicate(predicateASTNode); |
| } |
| |
| /** Make a semantic predicates label */ |
| public PredicateLabel(SemanticContext semCtx) { |
| super(SEMPRED); |
| this.semanticContext = semCtx; |
| } |
| |
| public int hashCode() { |
| return semanticContext.hashCode(); |
| } |
| |
| public boolean equals(Object o) { |
| if ( o==null ) { |
| return false; |
| } |
| if ( this == o ) { |
| return true; // equals if same object |
| } |
| if ( !(o instanceof PredicateLabel) ) { |
| return false; |
| } |
| return semanticContext.equals(((PredicateLabel)o).semanticContext); |
| } |
| |
| public boolean isSemanticPredicate() { |
| return true; |
| } |
| |
| public SemanticContext getSemanticContext() { |
| return semanticContext; |
| } |
| |
| public String toString() { |
| return "{"+semanticContext+"}?"; |
| } |
| |
| public String toString(Grammar g) { |
| return toString(); |
| } |
| } |