org.apache.el.parser
Class Token
public
class
Token
extends Object
implements Serializable
Describes the input token stream.
Field Summary |
int | beginColumn The column number of the first character of this Token. |
int | beginLine The line number of the first character of this Token. |
int | endColumn The column number of the last character of this Token. |
int | endLine The line number of the last character of this Token. |
String | image
The string image of the token. |
int | kind
An integer that describes the kind of this token. |
Token | next
A reference to the next regular (non-special) token from the input
stream. |
Token | specialToken
This field is used to access special tokens that occur prior to this
token, but after the immediately preceding regular (non-special) token.
|
Constructor Summary |
| Token()
No-argument constructor |
| Token(int kind)
Constructs a new token for the specified Image. |
| Token(int kind, String image)
Constructs a new token for the specified Image and Kind. |
public int beginColumn
The column number of the first character of this Token.
public int beginLine
The line number of the first character of this Token.
public int endColumn
The column number of the last character of this Token.
public int endLine
The line number of the last character of this Token.
public String image
The string image of the token.
public int kind
An integer that describes the kind of this token. This numbering
system is determined by JavaCCParser, and a table of these numbers is
stored in the file ...Constants.java.
A reference to the next regular (non-special) token from the input
stream. If this is the last token from the input stream, or if the
token manager has not read tokens beyond this one, this field is
set to null. This is true only if this token is also a regular
token. Otherwise, see below for a description of the contents of
this field.
public
Token specialToken
This field is used to access special tokens that occur prior to this
token, but after the immediately preceding regular (non-special) token.
If there are no such special tokens, this field is set to null.
When there are more than one such special token, this field refers
to the last of these special tokens, which in turn refers to the next
previous special token through its specialToken field, and so on
until the first special token (whose specialToken field is null).
The next fields of special tokens refer to other special tokens that
immediately follow it (without an intervening regular token). If there
is no such token, this field is null.
public Token()
No-argument constructor
public Token(int kind)
Constructs a new token for the specified Image.
public Token(int kind, String image)
Constructs a new token for the specified Image and Kind.
public Object getValue()
An optional attribute value of the Token.
Tokens which are not used as syntactic sugar will often contain
meaningful values that will be used later on by the compiler or
interpreter. This attribute value is often different from the image.
Any subclass of Token that actually wants to return a non-null value can
override this method as appropriate.
public static
Token newToken(int ofKind, String image)
Returns a new Token object, by default. However, if you want, you
can create and return subclass objects based on the value of ofKind.
Simply add the cases to the switch for all those special cases.
For example, if you have a subclass of Token called IDToken that
you want to create if ofKind is ID, simply add something like :
case MyParserConstants.ID : return new IDToken(ofKind, image);
to the following switch statement. Then you can cast matchedToken
variable to the appropriate type and use sit in your lexical actions.
public static
Token newToken(int ofKind)
public String toString()
Returns the image.
Copyright © 2000-2011 Apache Software Foundation. All Rights Reserved.