view storage/core/src/main/java/com/redhat/thermostat/storage/core/Query.java @ 922:beda9a88a646

Fix query to allow chain where clauses review-thread: http://icedtea.classpath.org/pipermail/thermostat/2013-January/005238.html reviewwed-by: jerboaa
author Mario Torre <neugens.limasoftware@gmail.com>
date Fri, 18 Jan 2013 19:39:01 +0100
parents 4de458324cf9
children ccac9bcabaa0
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/*
 * Copyright 2012 Red Hat, Inc.
 *
 * This file is part of Thermostat.
 *
 * Thermostat is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published
 * by the Free Software Foundation; either version 2, or (at your
 * option) any later version.
 *
 * Thermostat 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
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with Thermostat; see the file COPYING.  If not see
 * <http://www.gnu.org/licenses/>.
 *
 * Linking this code with other modules is making a combined work
 * based on this code.  Thus, the terms and conditions of the GNU
 * General Public License cover the whole combination.
 *
 * As a special exception, the copyright holders of this code give
 * you permission to link this code with independent modules to
 * produce an executable, regardless of the license terms of these
 * independent modules, and to copy and distribute the resulting
 * executable under terms of your choice, provided that you also
 * meet, for each linked independent module, the terms and conditions
 * of the license of that module.  An independent module is a module
 * which is not derived from or based on this code.  If you modify
 * this code, you may extend this exception to your version of the
 * library, but you are not obligated to do so.  If you do not wish
 * to do so, delete this exception statement from your version.
 */

package com.redhat.thermostat.storage.core;

import com.redhat.thermostat.storage.model.Pojo;

/**
 * Describes what data should be fetched.
 */
public interface Query<T extends Pojo> {

    enum Criteria {
        EQUALS,
        NOT_EQUAL_TO,
        GREATER_THAN,
        GREATER_THAN_OR_EQUAL_TO,
        LESS_THAN,
        LESS_THAN_OR_EQUAL_TO,
    }
    
    enum SortDirection {
        ASCENDING(1),
        DESCENDING(-1);

        private int value;

        private SortDirection(int value) {
            this.value = value;
        }

        public int getValue() {
            return value;
        }
    }

    <S> void where(Key<S> key, Criteria criteria, S value);
    
    void sort(Key<?> key, SortDirection direction);

    void limit(int n);

    Cursor<T> execute();

}