From 6bf4b90c90f15f4ab60833bddf5b5756d1a6b1f6 Mon Sep 17 00:00:00 2001 From: Elizabeth Alexander Hunt Date: Thu, 2 Jul 2026 11:55:17 -0700 Subject: Init --- .../cs5300/project-three/cfgparser/Grammar.java | 65 ++++++++++++++++++++++ 1 file changed, 65 insertions(+) create mode 100644 Homework/cs5300/project-three/cfgparser/Grammar.java (limited to 'Homework/cs5300/project-three/cfgparser/Grammar.java') diff --git a/Homework/cs5300/project-three/cfgparser/Grammar.java b/Homework/cs5300/project-three/cfgparser/Grammar.java new file mode 100644 index 0000000..4de9ae4 --- /dev/null +++ b/Homework/cs5300/project-three/cfgparser/Grammar.java @@ -0,0 +1,65 @@ +/* + * To change this license header, choose License Headers in Project Properties. + * To change this template file, choose Tools | Templates + * and open the template in the editor. + */ +package cfgparser; + +import java.io.IOException; +import java.util.ArrayList; +import java.util.HashSet; +import org.antlr.v4.runtime.ANTLRFileStream; +import org.antlr.v4.runtime.BufferedTokenStream; +import org.antlr.v4.runtime.ParserRuleContext; +import org.antlr.v4.runtime.tree.ParseTreeWalker; +import parser.Rule; + +/** + * + * @author edwajohn + */ +public class Grammar { + + private String name; + private ArrayList rules; + private String startSymbol; + + public Grammar(String filename) throws IOException { + GrammarLexer cfglexer = new GrammarLexer(new ANTLRFileStream(filename)); + GrammarParser cfgparser = new GrammarParser(new BufferedTokenStream(cfglexer)); + ParserRuleContext tree = cfgparser.getContext(); // parse + + GrammarParser.GoalContext context = cfgparser.goal(); + + // Walk it and attach our listener + GrammarListenerImpl listener = new GrammarListenerImpl(); + ParseTreeWalker walker = new ParseTreeWalker(); + walker.walk(listener, context); + name = listener.name; + rules = listener.rules; + startSymbol = listener.startSymbol; + } + + public ArrayList getRules() { + return rules; + } + + public String getName() { + return name; + } + + public ArrayList getSymbols() { + HashSet symbols = new HashSet<>(); + for (Rule rule : rules) { + symbols.add(rule.getLhs()); + for (String symbol : rule.getRhs()) { + symbols.add(symbol); + } + } + return new ArrayList<>(symbols); + } + + public String getStartSymbol() { + return startSymbol; + } +} -- cgit v1.3