Merge pull request antlr#1748 from parrt/rm-xpath-grammar

Fixes antlr#1620. Make handbuilt lexer to avoid cyclic dependence of tool and plugin.

Author: parrt

runtime/Java/src/org/antlr/v4/runtime/tree/xpath/XPathLexer.g4

@@ -0,0 +1,179 @@
+/*
+ * Copyright (c) 2012-2016 The ANTLR Project. All rights reserved.
+ * Use of this file is governed by the BSD 3-clause license that
+ * can be found in the LICENSE.txt file in the project root.
+ */
+package org.antlr.v4.runtime.tree.xpath;
+
+import org.antlr.v4.runtime.CharStream;
+import org.antlr.v4.runtime.CommonToken;
+import org.antlr.v4.runtime.Lexer;
+import org.antlr.v4.runtime.LexerNoViableAltException;
+import org.antlr.v4.runtime.Token;
+import org.antlr.v4.runtime.Vocabulary;
+import org.antlr.v4.runtime.VocabularyImpl;
+import org.antlr.v4.runtime.atn.ATN;
+import org.antlr.v4.runtime.misc.Interval;
+
+/** Mimic the old XPathLexer from .g4 file */
+public class XPathLexer extends Lexer {
+	public static final int
+		TOKEN_REF=1, RULE_REF=2, ANYWHERE=3, ROOT=4, WILDCARD=5, BANG=6, ID=7,
+		STRING=8;
+	public static String[] modeNames = {
+		"DEFAULT_MODE"
+	};
+
+	public static final String[] ruleNames = {
+		"ANYWHERE", "ROOT", "WILDCARD", "BANG", "ID", "NameChar", "NameStartChar",
+		"STRING"
+	};
+
+	private static final String[] _LITERAL_NAMES = {
+		null, null, null, "'//'", "'/'", "'*'", "'!'"
+	};
+	private static final String[] _SYMBOLIC_NAMES = {
+		null, "TOKEN_REF", "RULE_REF", "ANYWHERE", "ROOT", "WILDCARD", "BANG",
+		"ID", "STRING"
+	};
+	public static final Vocabulary VOCABULARY = new VocabularyImpl(_LITERAL_NAMES, _SYMBOLIC_NAMES);
+
+	/**
+	 * @deprecated Use {@link #VOCABULARY} instead.
+	 */
+	@Deprecated
+	public static final String[] tokenNames;
+	static {
+		tokenNames = new String[_SYMBOLIC_NAMES.length];
+		for (int i = 0; i < tokenNames.length; i++) {
+			tokenNames[i] = VOCABULARY.getLiteralName(i);
+			if (tokenNames[i] == null) {
+				tokenNames[i] = VOCABULARY.getSymbolicName(i);
+			}
+
+			if (tokenNames[i] == null) {
+				tokenNames[i] = "<INVALID>";
+			}
+		}
+	}
+
+	@Override
+	public String getGrammarFileName() { return "XPathLexer.g4"; }
+
+	@Override
+	public String[] getRuleNames() { return ruleNames; }
+
+	@Override
+	public String[] getModeNames() { return modeNames; }
+
+	@Override
+	@Deprecated
+	public String[] getTokenNames() {
+		return tokenNames;
+	}
+
+	@Override
+	public Vocabulary getVocabulary() {
+		return VOCABULARY;
+	}
+
+	@Override
+	public ATN getATN() {
+		return null;
+	}
+
+	protected int line = 1;
+	protected int charPositionInLine = 0;
+
+	public XPathLexer(CharStream input) {
+		super(input);
+	}
+
+	@Override
+	public Token nextToken() {
+		_tokenStartCharIndex = _input.index();
+		CommonToken t = null;
+		while ( t==null ) {
+			switch ( _input.LA(1) ) {
+				case '/':
+					consume();
+					if ( _input.LA(1)=='/' ) {
+						consume();
+						t = new CommonToken(ANYWHERE, "//");
+					}
+					else {
+						t = new CommonToken(ROOT, "/");
+					}
+					break;
+				case '*':
+					consume();
+					t = new CommonToken(WILDCARD, "*");
+					break;
+				case '!':
+					consume();
+					t = new CommonToken(BANG, "!");
+					break;
+				case '\'':
+					String s = matchString();
+					t = new CommonToken(STRING, s);
+					break;
+				case CharStream.EOF :
+					return new CommonToken(EOF, "<EOF>");
+				default:
+					if ( isNameStartChar(_input.LA(1)) ) {
+						String id = matchID();
+						if ( Character.isUpperCase(id.charAt(0)) ) t = new CommonToken(TOKEN_REF, id);
+						else t = new CommonToken(RULE_REF, id);
+					}
+					else {
+						throw new LexerNoViableAltException(this, _input, _tokenStartCharIndex, null);
+					}
+					break;
+			}
+		}
+		t.setStartIndex(_tokenStartCharIndex);
+		t.setCharPositionInLine(_tokenStartCharIndex);
+		t.setLine(line);
+		return t;
+	}
+
+	public void consume() {
+		int curChar = _input.LA(1);
+		if ( curChar=='\n' ) {
+			line++;
+			charPositionInLine=0;
+		}
+		else {
+			charPositionInLine++;
+		}
+		_input.consume();
+	}
+
+	@Override
+	public int getCharPositionInLine() {
+		return charPositionInLine;
+	}
+
+	public String matchID() {
+		int start = _input.index();
+		consume(); // drop start char
+		while ( isNameChar(_input.LA(1)) ) {
+			consume();
+		}
+		return _input.getText(Interval.of(start,_input.index()-1));
+	}
+
+	public String matchString() {
+		int start = _input.index();
+		consume(); // drop first quote
+		while ( _input.LA(1)!='\'' ) {
+			consume();
+		}
+		consume(); // drop last quote
+		return _input.getText(Interval.of(start,_input.index()-1));
+	}
+
+	public boolean isNameChar(int c) { return Character.isUnicodeIdentifierPart(c); }
+
+	public boolean isNameStartChar(int c) { return Character.isUnicodeIdentifierStart(c); }
+}