org.antlr.v4.runtime

Interface TokenStream

All Superinterfaces:

IntStream

All Known Implementing Classes:

BufferedTokenStream, CommonTokenStream, UnbufferedTokenStream

public interface TokenStream
extends IntStream

An IntStream whose symbols are Token instances.

Field Summary

Fields inherited from interface org.antlr.v4.runtime.IntStream

EOF, UNKNOWN_SOURCE_NAME

Method Summary

Methods

Modifier and Type	Method and Description
Token	get(int index) Gets the Token at the specified index in the stream.
String	getText() Return the text of all tokens in the stream.
String	getText(Interval interval) Return the text of all tokens within the specified interval.
String	getText(RuleContext ctx) Return the text of all tokens in the source interval of the specified context.
String	getText(Token start, Token stop) Return the text of all tokens in this stream between start and stop (inclusive).
TokenSource	getTokenSource() Gets the underlying TokenSource which provides tokens for this stream.
Token	LT(int k) Get the Token instance associated with the value returned by LA(k).

Methods inherited from interface org.antlr.v4.runtime.IntStream

consume, getSourceName, index, LA, mark, release, seek, size

Method Detail

LT

Token LT(int k)

Get the Token instance associated with the value returned by LA(k). This method has the same pre- and post-conditions as IntStream.LA(int). In addition, when the preconditions of this method are met, the return value is non-null and the value of LT(k).getType()==LA(k).

See Also:

IntStream.LA(int)

get

Token get(int index)

Gets the Token at the specified 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 IntStream.seek(int). If the behavior of seek(index) is unspecified for the current state and given index, then the behavior of this method is also unspecified.

The symbol referred to by index differs from seek() only in the case of filtering streams where index lies before the end of the stream. Unlike seek(), this method does not adjust index to point to a non-ignored symbol.

Throws:

IllegalArgumentException - if {code index} is less than 0

UnsupportedOperationException - if the stream does not support retrieving the token at the specified index

getTokenSource

TokenSource getTokenSource()

Gets the underlying TokenSource which provides tokens for this stream.

getText

String getText(Interval interval)

Return the text of all tokens within the specified interval. This method behaves like the following code (including potential exceptions for violating preconditions of get(int), 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();
 }
 

Parameters:

interval - The interval of tokens within this stream to get text for.

Returns:

The text of all tokens within the specified interval in this stream.

Throws:

NullPointerException - if interval is null

getText

String getText()

Return the text of all tokens in the stream. This method behaves like the following code, including potential exceptions from the calls to IntStream.size() and getText(Interval), but may be optimized by the specific implementation.

 TokenStream stream = ...;
 String text = stream.getText(new Interval(0, stream.size()));
 

Returns:

The text of all tokens in the stream.

getText

String getText(RuleContext ctx)

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 getText(Interval), but may be optimized by the specific implementation.

If 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());
 

Parameters:

ctx - The context providing the source interval of tokens to get text for.

Returns:

The text of all tokens within the source interval of ctx.

getText

String getText(Token start,
             Token stop)

Return the text of all tokens in this stream between start and stop (inclusive).

If the specified start or stop token was not provided by this stream, or if the stop occurred before the start token, the behavior is unspecified.

For streams which ensure that the Token.getTokenIndex() 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();
 }
 

Parameters:

start - The first token in the interval to get text for.

stop - The last token in the interval to get text for (inclusive).

Returns:

The text of all tokens lying between the specified start and stop tokens.

Throws:

UnsupportedOperationException - if this stream does not support this method for the specified tokens