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A collection of tests for ANTLR 4 Runtime libraries.

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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.
 */
using System;
using System.Collections.ObjectModel;
using Antlr4.Runtime.Misc;
using Antlr4.Runtime.Sharpen;

namespace Antlr4.Runtime.Atn
{
    /// An ATN transition between any two ATN states.
    /// 
    /// An ATN transition between any two ATN states.  Subclasses define
    /// atom, set, epsilon, action, predicate, rule transitions.
    /// This is a one way link.  It emanates from a state (usually via a list of
    /// transitions) and has a target state.
    /// Since we never have to change the ATN transitions once we construct it,
    /// we can fix these transitions as specific classes. The DFA transitions
    /// on the other hand need to update the labels as it adds transitions to
    /// the states. We'll use the term Edge for the DFA to distinguish them from
    /// ATN transitions.
    /// 
    public abstract class Transition
    {
        public static readonly ReadOnlyCollection serializationNames = new ReadOnlyCollection(Arrays.AsList("INVALID", "EPSILON", "RANGE", "RULE", "PREDICATE", "ATOM", "ACTION", "SET", "NOT_SET", "WILDCARD", "PRECEDENCE"));

        /// The target of this transition.
        /// The target of this transition.
        [NotNull]
        public ATNState target;

        protected internal Transition(ATNState target)
        {
            if (target == null)
            {
                throw new ArgumentNullException("target cannot be null.");
            }
            this.target = target;
        }

        public abstract TransitionType TransitionType
        {
            get;
        }

        /// Determines if the transition is an "epsilon" transition.
        /// 
        /// Determines if the transition is an "epsilon" transition.
        /// The default implementation returns
        /// 
        /// .
        /// 
        /// 
        ///
        /// 
        /// if traversing this transition in the ATN does not
        /// consume an input symbol; otherwise,
        /// 
        /// if traversing this
        /// transition consumes (matches) an input symbol.
        /// 
        public virtual bool IsEpsilon
        {
            get
            {
                return false;
            }
        }

        public virtual IntervalSet Label
        {
            get
            {
                return null;
            }
        }

        public abstract bool Matches(int symbol, int minVocabSymbol, int maxVocabSymbol);
    }
}