termmap.java

MG4J (Managing Gigabytes for Java) is a free full-text search engine for large document collections

package it.unimi.dsi.mg4j.index;

/*		 
 * MG4J: Managing Gigabytes for Java
 *
 * Copyright (C) 2005-2007 Sebastiano Vigna 
 *
 *  This library is free software; you can redistribute it and/or modify it
 *  under the terms of the GNU Lesser General Public License as published by the Free
 *  Software Foundation; either version 2.1 of the License, or (at your option)
 *  any later version.
 *
 *  This library is distributed in the hope that it will be useful, but
 *  WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 *  or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
 *  for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 *
 */

import it.unimi.dsi.mg4j.util.MutableString;
import it.unimi.dsi.util.StringMap;

/** A map from terms to numbers (and possibly viceversa).
 * 
 * <p>The possibility of retrieving terms can be checked for by calling {@link #hasTerms()}.
 * 
 * @author Sebastiano Vigna 
 * @since 0.9.2
 * @deprecated As of MG4J 2.1, replaced by {@link StringMap}.
 */

@Deprecated
public interface TermMap {

	/** Returns the ordinal number corresponding to the given term, or possibly (but not necessarily) -1 if the term was not indexed.
	 * 
	 * <p>We intentionally prefer &ldquo;ordinal number&rdquo; to &ldquo;index&rdquo; because of the obvious
	 * confusion that the latter term can cause.
	 * 
	 * @param term a term.
	 * @return its ordinal number, or possibly (but not necessarily) -1 if the term was not indexed.
	 */
	public int getNumber( CharSequence term );

	/** Returns true if this prefix map supports {@linkplain #getTerm(int) term retrieval}. 
	 * 
	 * @return true if this prefix map supports {@linkplain #getTerm(int) term retrieval}.
	 */
	
	public boolean hasTerms();
	
	/** Returns the term corresponding to the given ordinal number (optional operation).
	 * 
	 * @param number a term ordinal number.
	 * @return the corresponding term, or possibly (but not necessarily) <code>null</code> if the term was not indexed.
	 */

	public CharSequence getTerm( int number );

	/** Writes in the given mutable string the term corresponding to the given ordinal number (optional operation).
	 * 
	 * @param number a term ordinal number.
	 * @param term a mutable string that will be filled with the corresponding term.
	 * @return <code>term</code>, or possibly (but not necessarily) <code>null</code> if the term was not indexed.
	 */

	public MutableString getTerm( int number, MutableString term );

	/** Returns the number of terms in this term map. 
	 * @return the number of terms in this term map.
	 */
	public int size();
	
}