+ public:
+ virtual ~TokenStream();
+
+ virtual Token* LT(ssize_t k) = 0;
+
+ ///
+ /// Gets the at the specified {@code index} in the stream. When
+ /// the preconditions of this method are met, the return value is non-null.
+ ///
+ /// The preconditions for this method are the same as the preconditions of
+ /// . If the behavior of {@code seek(index)} is
+ /// unspecified for the current state and given {@code index}, then the
+ /// behavior of this method is also unspecified.
+ ///
+ /// The symbol referred to by {@code index} differs from {@code seek()} only
+ /// in the case of filtering streams where {@code index} lies before the end
+ /// of the stream. Unlike {@code seek()}, this method does not adjust
+ /// {@code index} to point to a non-ignored symbol.
+ ///
+ /// if {code index} is less than 0
+ /// if the stream does not support
+ /// retrieving the token at the specified index
+ virtual Token* get(size_t index) const = 0;
+
+ /// Gets the underlying TokenSource which provides tokens for this stream.
+ virtual TokenSource* getTokenSource() const = 0;
+
+ ///
+ /// Return the text of all tokens within the specified {@code interval}. This
+ /// method behaves like the following code (including potential exceptions
+ /// for violating preconditions of , but may be optimized by the
+ /// specific implementation.
+ ///
+ ///
+ /// TokenStream stream = ...;
+ /// String text = "";
+ /// for (int i = interval.a; i <= interval.b; i++) {
+ /// text += stream.get(i).getText();
+ /// }
+ ///
+ ///
+ /// The interval of tokens within this stream to get text
+ /// for.
+ /// The text of all tokens within the specified interval in this
+ /// stream.
+ ///
+ /// if {@code interval} is {@code null}
+ virtual std::string getText(const misc::Interval &interval) = 0;
+
+ ///
+ /// Return the text of all tokens in the stream. This method behaves like the
+ /// following code, including potential exceptions from the calls to
+ /// and , but may be
+ /// optimized by the specific implementation.
+ ///
+ ///
+ /// TokenStream stream = ...;
+ /// String text = stream.getText(new Interval(0, stream.size()));
+ ///
+ ///
+ /// The text of all tokens in the stream.
+ virtual std::string getText() = 0;
+
+ ///
+ /// Return the text of all tokens in the source interval of the specified
+ /// context. This method behaves like the following code, including potential
+ /// exceptions from the call to , but may be
+ /// optimized by the specific implementation.
+ ///
+ /// If {@code ctx.getSourceInterval()} does not return a valid interval of
+ /// tokens provided by this stream, the behavior is unspecified.
+ ///
+ ///
+ /// TokenStream stream = ...;
+ /// String text = stream.getText(ctx.getSourceInterval());
+ ///
+ ///
+ /// The context providing the source interval of tokens to get
+ /// text for.
+ /// The text of all tokens within the source interval of {@code ctx}.
+ virtual std::string getText(RuleContext *ctx) = 0;
+
+ ///
+ /// Return the text of all tokens in this stream between {@code start} and
+ /// {@code stop} (inclusive).
+ ///
+ /// If the specified {@code start} or {@code stop} token was not provided by
+ /// this stream, or if the {@code stop} occurred before the {@code start}
+ /// token, the behavior is unspecified.
+ ///
+ /// For streams which ensure that the method is
+ /// accurate for all of its provided tokens, this method behaves like the
+ /// following code. Other streams may implement this method in other ways
+ /// provided the behavior is consistent with this at a high level.
+ ///
+ ///
+ /// TokenStream stream = ...;
+ /// String text = "";
+ /// for (int i = start.getTokenIndex(); i <= stop.getTokenIndex(); i++) {
+ /// text += stream.get(i).getText();
+ /// }
+ ///
+ ///
+ /// The first token in the interval to get text for.
+ /// The last token in the interval to get text for (inclusive).
+ /// The text of all tokens lying between the specified {@code start}
+ /// and {@code stop} tokens.
+ ///
+ /// if this stream does not support
+ /// this method for the specified tokens
+ virtual std::string getText(Token *start, Token *stop) = 0;
+ };
+
+} // namespace antlr4