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1 files changed, 65 insertions, 0 deletions

diff --git a/Homework/cs5300/project-three/cfgparser/Grammar.java b/Homework/cs5300/project-three/cfgparser/Grammar.java
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+/*
+ * 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<Rule> 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<Rule> getRules() {
+    return rules;
+  }
+
+  public String getName() {
+    return name;
+  }
+
+  public ArrayList<String> getSymbols() {
+    HashSet<String> 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;
+  }
+}