IZTokenizer Class Reference

A tokenizer divides a string into tokens. More...

Inheritance diagram for IZTokenizer:

TZTokenizer TZExpressionTokenizer TZGenericSQLTokenizer TZInterbaseTokenizer TZMySQLTokenizer TZOracleTokenizer TZPostgreSQLTokenizer TZSQLiteTokenizer TZSybaseTokenizer

List of all members.

Public Member Functions

TZCommentState GetCommentState ()
TZNumberState GetNumberState ()
TZQuoteState GetQuoteState ()
TZSymbolState GetSymbolState ()
TZWhitespaceState GetWhitespaceState ()
TZWordState GetWordState ()
TZTokenDynArray TokenizeBuffer (const string Buffer, TZTokenOptions Options)
TStrings TokenizeBufferToList (const string Buffer, TZTokenOptions Options)
TZTokenDynArray TokenizeStream (TStream Stream, TZTokenOptions Options)
TStrings TokenizeStreamToList (TStream Stream, TZTokenOptions Options)


Detailed Description

A tokenizer divides a string into tokens.

This class is highly customizable with regard to exactly how this division occurs, but it also has defaults that are suitable for many languages. This class assumes that the character values read from the string lie in the range 0-255. For example, the Unicode value of a capital A is 65, so System.out.println((char)65); prints out a capital A.

The behavior of a tokenizer depends on its character state table. This table is an array of 256 TokenizerState states. The state table decides which state to enter upon reading a character from the input string.

For example, by default, upon reading an 'A', a tokenizer will enter a "word" state. This means the tokenizer will ask a WordState object to consume the 'A', along with the characters after the 'A' that form a word. The state's responsibility is to consume characters and return a complete token.

The default table sets a SymbolState for every character from 0 to 255, and then overrides this with: <blockquote>

        From    To     State
          0     ' '    whitespaceState
         'a'    'z'    wordState
         'A'    'Z'    wordState
        160     255    wordState
         '0'    '9'    numberState
         '-'    '-'    numberState
         '.'    '.'    numberState
         '"'    '"'    quoteState
        '\''   '\''    quoteState
         '/'    '/'    slashState
    
</blockquote> In addition to allowing modification of the state table, this class makes each of the states above available. Some of these states are customizable. For example, wordState allows customization of what characters can be part of a word, after the first character.

Definition at line 587 of file ZTokenizer.pas.


Member Function Documentation

TZCommentState IZTokenizer::GetCommentState (  ) 

Reimplemented in TZTokenizer.

TZNumberState IZTokenizer::GetNumberState (  ) 

Reimplemented in TZTokenizer.

TZQuoteState IZTokenizer::GetQuoteState (  ) 

Reimplemented in TZTokenizer.

TZSymbolState IZTokenizer::GetSymbolState (  ) 

Reimplemented in TZTokenizer.

TZWhitespaceState IZTokenizer::GetWhitespaceState (  ) 

Reimplemented in TZTokenizer.

TZWordState IZTokenizer::GetWordState (  ) 

Reimplemented in TZTokenizer.

TZTokenDynArray IZTokenizer::TokenizeBuffer ( const string  Buffer,
TZTokenOptions  Options 
)

Reimplemented in TZTokenizer.

TStrings IZTokenizer::TokenizeBufferToList ( const string  Buffer,
TZTokenOptions  Options 
)

Reimplemented in TZTokenizer.

TZTokenDynArray IZTokenizer::TokenizeStream ( TStream  Stream,
TZTokenOptions  Options 
)

Reimplemented in TZTokenizer.

TStrings IZTokenizer::TokenizeStreamToList ( TStream  Stream,
TZTokenOptions  Options 
)

Reimplemented in TZTokenizer.


The documentation for this class was generated from the following file:

Generated on Wed Dec 30 08:42:45 2009 for zeoslib by  doxygen 1.5.7.1