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Statistical sampling library for use in virtdata 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.DecisionState;
import org.antlr.v4.runtime.misc.IntervalSet;

/** The root of the ANTLR exception hierarchy. In general, ANTLR tracks just
 *  3 kinds of errors: prediction errors, failed predicate errors, and
 *  mismatched input errors. In each case, the parser knows where it is
 *  in the input, where it is in the ATN, the rule invocation stack,
 *  and what kind of problem occurred.
 */
public class RecognitionException extends RuntimeException {
	/** The {@link Recognizer} where this exception originated. */
	private final Recognizer recognizer;

	private final RuleContext ctx;

	private final IntStream input;

	/**
	 * The current {@link Token} when an error occurred. Since not all streams
	 * support accessing symbols by index, we have to track the {@link Token}
	 * instance itself.
	 */
	private Token offendingToken;

	private int offendingState = -1;

	public RecognitionException(Recognizer recognizer,
								IntStream input,
								ParserRuleContext ctx)
	{
		this.recognizer = recognizer;
		this.input = input;
		this.ctx = ctx;
		if ( recognizer!=null ) this.offendingState = recognizer.getState();
	}

	public RecognitionException(String message,
								Recognizer recognizer,
								IntStream input,
								ParserRuleContext ctx)
	{
		super(message);
		this.recognizer = recognizer;
		this.input = input;
		this.ctx = ctx;
		if ( recognizer!=null ) this.offendingState = recognizer.getState();
	}

	/**
	 * Get the ATN state number the parser was in at the time the error
	 * occurred. For {@link NoViableAltException} and
	 * {@link LexerNoViableAltException} exceptions, this is the
	 * {@link DecisionState} number. For others, it is the state whose outgoing
	 * edge we couldn't match.
	 *
	 * 

If the state number is not known, this method returns -1.

*/ public int getOffendingState() { return offendingState; } protected final void setOffendingState(int offendingState) { this.offendingState = offendingState; } /** * Gets the set of input symbols which could potentially follow the * previously matched symbol at the time this exception was thrown. * *

If the set of expected tokens is not known and could not be computed, * this method returns {@code null}.

* * @return The set of token types that could potentially follow the current * state in the ATN, or {@code null} if the information is not available. */ public IntervalSet getExpectedTokens() { if (recognizer != null) { return recognizer.getATN().getExpectedTokens(offendingState, ctx); } return null; } /** * Gets the {@link RuleContext} at the time this exception was thrown. * *

If the context is not available, this method returns {@code null}.

* * @return The {@link RuleContext} at the time this exception was thrown. * If the context is not available, this method returns {@code null}. */ public RuleContext getCtx() { return ctx; } /** * Gets the input stream which is the symbol source for the recognizer where * this exception was thrown. * *

If the input stream is not available, this method returns {@code null}.

* * @return The input stream which is the symbol source for the recognizer * where this exception was thrown, or {@code null} if the stream is not * available. */ public IntStream getInputStream() { return input; } public Token getOffendingToken() { return offendingToken; } protected final void setOffendingToken(Token offendingToken) { this.offendingToken = offendingToken; } /** * Gets the {@link Recognizer} where this exception occurred. * *

If the recognizer is not available, this method returns {@code null}.

* * @return The recognizer where this exception occurred, or {@code null} if * the recognizer is not available. */ public Recognizer getRecognizer() { return recognizer; } }




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