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Home » lucene-3.0.1-src » org.apache » lucene » queryParser » [javadoc | source]
org.apache.lucene.queryParser
public class: Token [javadoc | source]
java.lang.Object
   org.apache.lucene.queryParser.Token
Describes the input token stream.
Field Summary
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. 
public  int beginLine    The line number of the first character of this Token. 
public  int beginColumn    The column number of the first character of this Token. 
public  int endLine    The line number of the last character of this Token. 
public  int endColumn    The column number of the last character of this Token. 
public  String image    The string image of the token. 
public  Token next    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. 
Constructor:
 public Token() 
 public Token(int kind) 
 public Token(int kind,
    String image) 
    Constructs a new token for the specified Image and Kind.
Method from org.apache.lucene.queryParser.Token Summary:
getValue,   newToken,   newToken,   toString
Methods from java.lang.Object:
clone,   equals,   finalize,   getClass,   hashCode,   notify,   notifyAll,   toString,   wait,   wait,   wait
Method from org.apache.lucene.queryParser.Token Detail:
 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) 
 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 String toString() 
    Returns the image.