package weka.datagenerators;
import java.io.IOException;
import java.util.Collection;
/**
* Defines common behaviors for lexers. A lexer splits a given input
* string into an array of string tokens, according to some particular
* rules.
*
* @author ywwong
* @version $Id: Lexer.java,v 1.1.1.1 2003/01/22 07:48:27 mbilenko Exp $
*/
abstract class Lexer {
/** The document reader. */
protected DocumentReader m_reader;
public Lexer(DocumentReader reader) { m_reader = reader; }
/** Parses the next token from the document reader.
*
* @return The next token if it's available; <code>null</code> if
* otherwise.
*/
public abstract String nextToken() throws IOException;
////// WEKA specific. //////
public abstract Collection getOptions();
}