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Cayenne Object Persistence Framework including all dependencies.
There is a newer version: 1.2.4
/* ====================================================================
 * 
 * The ObjectStyle Group Software License, version 1.1
 * ObjectStyle Group - http://objectstyle.org/
 * 
 * Copyright (c) 2002-2005, Andrei (Andrus) Adamchik and individual authors
 * of the software. All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 * 
 * 3. The end-user documentation included with the redistribution, if any,
 *    must include the following acknowlegement:
 *    "This product includes software developed by independent contributors
 *    and hosted on ObjectStyle Group web site (http://objectstyle.org/)."
 *    Alternately, this acknowlegement may appear in the software itself,
 *    if and wherever such third-party acknowlegements normally appear.
 * 
 * 4. The names "ObjectStyle Group" and "Cayenne" must not be used to endorse
 *    or promote products derived from this software without prior written
 *    permission. For written permission, email
 *    "andrus at objectstyle dot org".
 * 
 * 5. Products derived from this software may not be called "ObjectStyle"
 *    or "Cayenne", nor may "ObjectStyle" or "Cayenne" appear in their
 *    names without prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE OBJECTSTYLE GROUP OR
 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 * ====================================================================
 * 
 * This software consists of voluntary contributions made by many
 * individuals and hosted on ObjectStyle Group web site.  For more
 * information on the ObjectStyle Group, please see
 * .
 */ 
package org.objectstyle.cayenne.access;

import java.util.List;
import java.util.Map;

import org.objectstyle.cayenne.CayenneException;
import org.objectstyle.cayenne.map.DbEntity;

/**
 * Defines API of an iterator over the records returned as a result
 * of SelectQuery execution. Usually a ResultIterator is supported by
 * an open java.sql.ResultSet, therefore most of the methods would throw
 * checked exceptions. ResultIterators must be explicitly closed when the
 * user is done working with them.
 * 
 * For more information see Cayenne User Guide.
 * 
 * @author Andrei Adamchik
 */
public interface ResultIterator {
    
    /**
     * Returns all unread data rows from ResultSet and closes this iterator
     * if asked to do so.
     */
    public List dataRows(boolean close) throws CayenneException;
           
	/** 
	 * Returns true if there is at least one more record
	 * that can be read from the iterator.
	 */
	public boolean hasNextRow() throws CayenneException;
    
    /** 
	 * Returns the next result row as a Map.
	 */
    public Map nextDataRow() throws CayenneException;
    
    /**
     * Returns a map of ObjectId values from the next result row.
     * Primary key columns are determined from the provided DbEntity.
     * 
     * @since 1.1
     */
    public Map nextObjectId(DbEntity entity) throws CayenneException;
    
    /**
     * Skips current data row instead of reading it.
     */
    public void skipDataRow() throws CayenneException;
    
    /** 
     * Closes ResultIterator and associated ResultSet. This method must be
     * called explicitly when the user is finished processing the records.
     * Otherwise unused database resources will not be released properly.
     */  
    public void close() throws CayenneException;
    
    /**
     * Returns the number of columns in the result row.
     * 
     * @since 1.0.6
     */
    public int getDataRowWidth();
}