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Statistical sampling library for use in virtualdataset libraries, based on apache commons math 4

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/*
 * Copyright (c) 2012-2017 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;

import org.antlr.v4.runtime.atn.ATN;
import org.antlr.v4.runtime.atn.ATNSimulator;
import org.antlr.v4.runtime.atn.ParseInfo;
import org.antlr.v4.runtime.misc.Utils;

import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.WeakHashMap;
import java.util.concurrent.CopyOnWriteArrayList;

public abstract class Recognizer {
	public static final int EOF=-1;

	private static final Map> tokenTypeMapCache =
		new WeakHashMap>();
	private static final Map> ruleIndexMapCache =
		new WeakHashMap>();


	private List _listeners =
		new CopyOnWriteArrayList() {{
			add(ConsoleErrorListener.INSTANCE);
		}};

	protected ATNInterpreter _interp;

	private int _stateNumber = -1;

	/** Used to print out token names like ID during debugging and
	 *  error reporting.  The generated parsers implement a method
	 *  that overrides this to point to their String[] tokenNames.
	 *
	 * @deprecated Use {@link #getVocabulary()} instead.
	 */
	@Deprecated
	public abstract String[] getTokenNames();

	public abstract String[] getRuleNames();

	/**
	 * Get the vocabulary used by the recognizer.
	 *
	 * @return A {@link Vocabulary} instance providing information about the
	 * vocabulary used by the grammar.
	 */
	@SuppressWarnings("deprecation")
	public Vocabulary getVocabulary() {
		return VocabularyImpl.fromTokenNames(getTokenNames());
	}

	/**
	 * Get a map from token names to token types.
	 *
	 * 

Used for XPath and tree pattern compilation.

*/ public Map getTokenTypeMap() { Vocabulary vocabulary = getVocabulary(); synchronized (tokenTypeMapCache) { Map result = tokenTypeMapCache.get(vocabulary); if (result == null) { result = new HashMap(); for (int i = 0; i <= getATN().maxTokenType; i++) { String literalName = vocabulary.getLiteralName(i); if (literalName != null) { result.put(literalName, i); } String symbolicName = vocabulary.getSymbolicName(i); if (symbolicName != null) { result.put(symbolicName, i); } } result.put("EOF", Token.EOF); result = Collections.unmodifiableMap(result); tokenTypeMapCache.put(vocabulary, result); } return result; } } /** * Get a map from rule names to rule indexes. * *

Used for XPath and tree pattern compilation.

*/ public Map getRuleIndexMap() { String[] ruleNames = getRuleNames(); if (ruleNames == null) { throw new UnsupportedOperationException("The current recognizer does not provide a list of rule names."); } synchronized (ruleIndexMapCache) { Map result = ruleIndexMapCache.get(ruleNames); if (result == null) { result = Collections.unmodifiableMap(Utils.toMap(ruleNames)); ruleIndexMapCache.put(ruleNames, result); } return result; } } public int getTokenType(String tokenName) { Integer ttype = getTokenTypeMap().get(tokenName); if ( ttype!=null ) return ttype; return Token.INVALID_TYPE; } /** * If this recognizer was generated, it will have a serialized ATN * representation of the grammar. * *

For interpreters, we don't know their serialized ATN despite having * created the interpreter from it.

*/ public String getSerializedATN() { throw new UnsupportedOperationException("there is no serialized ATN"); } /** For debugging and other purposes, might want the grammar name. * Have ANTLR generate an implementation for this method. */ public abstract String getGrammarFileName(); /** * Get the {@link ATN} used by the recognizer for prediction. * * @return The {@link ATN} used by the recognizer for prediction. */ public abstract ATN getATN(); /** * Get the ATN interpreter used by the recognizer for prediction. * * @return The ATN interpreter used by the recognizer for prediction. */ public ATNInterpreter getInterpreter() { return _interp; } /** If profiling during the parse/lex, this will return DecisionInfo records * for each decision in recognizer in a ParseInfo object. * * @since 4.3 */ public ParseInfo getParseInfo() { return null; } /** * Set the ATN interpreter used by the recognizer for prediction. * * @param interpreter The ATN interpreter used by the recognizer for * prediction. */ public void setInterpreter(ATNInterpreter interpreter) { _interp = interpreter; } /** What is the error header, normally line/character position information? */ public String getErrorHeader(RecognitionException e) { int line = e.getOffendingToken().getLine(); int charPositionInLine = e.getOffendingToken().getCharPositionInLine(); return "line "+line+":"+charPositionInLine; } /** How should a token be displayed in an error message? The default * is to display just the text, but during development you might * want to have a lot of information spit out. Override in that case * to use t.toString() (which, for CommonToken, dumps everything about * the token). This is better than forcing you to override a method in * your token objects because you don't have to go modify your lexer * so that it creates a new Java type. * * @deprecated This method is not called by the ANTLR 4 Runtime. Specific * implementations of {@link ANTLRErrorStrategy} may provide a similar * feature when necessary. For example, see * {@link DefaultErrorStrategy#getTokenErrorDisplay}. */ @Deprecated public String getTokenErrorDisplay(Token t) { if ( t==null ) return ""; String s = t.getText(); if ( s==null ) { if ( t.getType()==Token.EOF ) { s = ""; } else { s = "<"+t.getType()+">"; } } s = s.replace("\n","\\n"); s = s.replace("\r","\\r"); s = s.replace("\t","\\t"); return "'"+s+"'"; } /** * @exception NullPointerException if {@code listener} is {@code null}. */ public void addErrorListener(ANTLRErrorListener listener) { if (listener == null) { throw new NullPointerException("listener cannot be null."); } _listeners.add(listener); } public void removeErrorListener(ANTLRErrorListener listener) { _listeners.remove(listener); } public void removeErrorListeners() { _listeners.clear(); } public List getErrorListeners() { return _listeners; } public ANTLRErrorListener getErrorListenerDispatch() { return new ProxyErrorListener(getErrorListeners()); } // subclass needs to override these if there are sempreds or actions // that the ATN interp needs to execute public boolean sempred(RuleContext _localctx, int ruleIndex, int actionIndex) { return true; } public boolean precpred(RuleContext localctx, int precedence) { return true; } public void action(RuleContext _localctx, int ruleIndex, int actionIndex) { } public final int getState() { return _stateNumber; } /** Indicate that the recognizer has changed internal state that is * consistent with the ATN state passed in. This way we always know * where we are in the ATN as the parser goes along. The rule * context objects form a stack that lets us see the stack of * invoking rules. Combine this and we have complete ATN * configuration information. */ public final void setState(int atnState) { // System.err.println("setState "+atnState); _stateNumber = atnState; // if ( traceATNStates ) _ctx.trace(atnState); } public abstract IntStream getInputStream(); public abstract void setInputStream(IntStream input); public abstract TokenFactory getTokenFactory(); public abstract void setTokenFactory(TokenFactory input); }




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