Token

All Known Subinterfaces:

WritableToken

All Known Implementing Classes:

CommonToken, RuleTagToken, TokenTagToken
```
public interface Token
```
A token has properties: text, type, line, character position in the line (so we can ignore tabs), token channel, index, and source from which we obtained this token.

Field Summary

Fields
Modifier and Type	Field and Description
`static int`	`DEFAULT_CHANNEL` All tokens go to the parser (unless skip() is called in that rule) on a particular "channel".
`static int`	`EOF`
`static int`	`EPSILON` During lookahead operations, this "token" signifies we hit rule end ATN state and did not follow it despite needing to.
`static int`	`HIDDEN_CHANNEL` Anything on different channel than DEFAULT_CHANNEL is not parsed by parser.
`static int`	`INVALID_TYPE`
`static int`	`MIN_USER_CHANNEL_VALUE` This is the minimum constant value which can be assigned to a user-defined token channel.
`static int`	`MIN_USER_TOKEN_TYPE`

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method and Description
`int`	`getChannel()` Return the channel this token.
`int`	`getCharPositionInLine()` The index of the first character of this token relative to the beginning of the line at which it occurs, 0..n-1
`CharStream`	`getInputStream()` Gets the `CharStream` from which this token was derived.
`int`	`getLine()` The line number on which the 1st character of this token was matched, line=1..n
`int`	`getStartIndex()` The starting character index of the token This method is optional; return -1 if not implemented.
`int`	`getStopIndex()` The last character index of the token.
`String`	`getText()` Get the text of the token.
`int`	`getTokenIndex()` An index from 0..n-1 of the token object in the input stream.
`TokenSource`	`getTokenSource()` Gets the `TokenSource` which created this token.
`int`	`getType()` Get the token type of the token

- Field Detail
  - INVALID_TYPE
```
static final int INVALID_TYPE
```
    See Also:
    
    Constant Field Values
  - EPSILON
```
static final int EPSILON
```
    During lookahead operations, this "token" signifies we hit rule end ATN state and did not follow it despite needing to.
    
    See Also:
    
    Constant Field Values
  - MIN_USER_TOKEN_TYPE
```
static final int MIN_USER_TOKEN_TYPE
```
    See Also:
    
    Constant Field Values
  - EOF
```
static final int EOF
```
    See Also:
    
    Constant Field Values
  - DEFAULT_CHANNEL
```
static final int DEFAULT_CHANNEL
```
    All tokens go to the parser (unless skip() is called in that rule) on a particular "channel". The parser tunes to a particular channel so that whitespace etc... can go to the parser on a "hidden" channel.
    
    See Also:
    
    Constant Field Values
  - HIDDEN_CHANNEL
```
static final int HIDDEN_CHANNEL
```
    Anything on different channel than DEFAULT_CHANNEL is not parsed by parser.
    
    See Also:
    
    Constant Field Values
  - MIN_USER_CHANNEL_VALUE
```
static final int MIN_USER_CHANNEL_VALUE
```
    This is the minimum constant value which can be assigned to a user-defined token channel.
    The non-negative numbers less than Token.MIN_USER_CHANNEL_VALUE are assigned to the predefined channels Token.DEFAULT_CHANNEL and Token.HIDDEN_CHANNEL.
    
    See Also:
    
    Token.getChannel(), Constant Field Values
- Method Detail
  - getText
```
String getText()
```
    Get the text of the token.
  - getType
```
int getType()
```
    Get the token type of the token
  - getLine
```
int getLine()
```
    The line number on which the 1st character of this token was matched, line=1..n
  - getCharPositionInLine
```
int getCharPositionInLine()
```
    The index of the first character of this token relative to the beginning of the line at which it occurs, 0..n-1
  - getChannel
```
int getChannel()
```
    Return the channel this token. Each token can arrive at the parser on a different channel, but the parser only "tunes" to a single channel. The parser ignores everything not on DEFAULT_CHANNEL.
  - getTokenIndex
```
int getTokenIndex()
```
    An index from 0..n-1 of the token object in the input stream. This must be valid in order to print token streams and use TokenRewriteStream. Return -1 to indicate that this token was conjured up since it doesn't have a valid index.
  - getStartIndex
```
int getStartIndex()
```
    The starting character index of the token This method is optional; return -1 if not implemented.
  - getStopIndex
```
int getStopIndex()
```
    The last character index of the token. This method is optional; return -1 if not implemented.
  - getTokenSource
```
TokenSource getTokenSource()
```
    Gets the TokenSource which created this token.
  - getInputStream
```
CharStream getInputStream()
```
    Gets the CharStream from which this token was derived.

Interface Token

Field Summary

Method Summary

Field Detail

INVALID_TYPE

EPSILON

MIN_USER_TOKEN_TYPE

EOF

DEFAULT_CHANNEL

HIDDEN_CHANNEL

MIN_USER_CHANNEL_VALUE

Method Detail

getText

getType

getLine

getCharPositionInLine

getChannel

getTokenIndex

getStartIndex

getStopIndex

getTokenSource

getInputStream