src/java.base/share/classes/java/util/spi/CalendarDataProvider.java

/*
 * Copyright (c) 2012, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code 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
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

package java.util.spi;

import java.util.Calendar;
import java.util.Locale;

/**
 * An abstract class for service providers that provide locale-dependent {@link
 * Calendar} parameters.
 *
 * @author Masayoshi Okutsu
 * @since 1.8
 * @see CalendarNameProvider
 */
public abstract class CalendarDataProvider extends LocaleServiceProvider {

    /**
     * Sole constructor. (For invocation by subclass constructors, typically
     * implicit.)
     */
    protected CalendarDataProvider() {
    }

    /**
     * Returns the first day of a week in the given {@code locale}. This
     * information is required by {@link Calendar} to support operations on the
     * week-related calendar fields.
     *
     * @param locale
     *        the desired locale
     * @return the first day of a week; one of {@link Calendar#SUNDAY} ..
     *         {@link Calendar#SATURDAY},
     *         or 0 if the value isn't available for the {@code locale}
     * @throws NullPointerException
     *         if {@code locale} is {@code null}.
     * @see java.util.Calendar#getFirstDayOfWeek()
     * @see <a href="../Calendar.html#first_week">First Week</a>
     */
    public abstract int getFirstDayOfWeek(Locale locale);

    /**
     * Returns the minimal number of days required in the first week of a
     * year. This information is required by {@link Calendar} to determine the
     * first week of a year. Refer to the description of <a
     * href="../Calendar.html#first_week"> how {@code Calendar} determines
     * the first week</a>.
     *
     * @param locale
     *        the desired locale
     * @return the minimal number of days of the first week,
     *         or 0 if the value isn't available for the {@code locale}
     * @throws NullPointerException
     *         if {@code locale} is {@code null}.
     * @see java.util.Calendar#getMinimalDaysInFirstWeek()
     */
    public abstract int getMinimalDaysInFirstWeek(Locale locale);
}