001/*
002 *  Copyright 2001-2007 Stephen Colebourne
003 *
004 *  Licensed under the Apache License, Version 2.0 (the "License");
005 *  you may not use this file except in compliance with the License.
006 *  You may obtain a copy of the License at
007 *
008 *      http://www.apache.org/licenses/LICENSE-2.0
009 *
010 *  Unless required by applicable law or agreed to in writing, software
011 *  distributed under the License is distributed on an "AS IS" BASIS,
012 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 *  See the License for the specific language governing permissions and
014 *  limitations under the License.
015 */
016package org.joda.time.base;
017
018/**
019 * BaseLocal is an abstract implementation of ReadablePartial that
020 * use a local milliseconds internal representation.
021 * <p>
022 * This class should generally not be used directly by API users.
023 * The {@link org.joda.time.ReadablePartial} interface should be used when different 
024 * kinds of partial objects are to be referenced.
025 * <p>
026 * BasePartial subclasses may be mutable and not thread-safe.
027 *
028 * @author Stephen Colebourne
029 * @since 1.5
030 */
031public abstract class BaseLocal
032        extends AbstractPartial {
033
034    /** Serialization version */
035    private static final long serialVersionUID = 276453175381783L;
036
037    //-----------------------------------------------------------------------
038    /**
039     * Constructs a partial with the current time, using ISOChronology in
040     * the default zone to extract the fields.
041     * <p>
042     * The constructor uses the default time zone, resulting in the local time
043     * being initialised. Once the constructor is complete, all further calculations
044     * are performed without reference to a timezone (by switching to UTC).
045     */
046    protected BaseLocal() {
047        super();
048    }
049
050    //-----------------------------------------------------------------------
051    /**
052     * Gets the local milliseconds from the Java epoch
053     * of 1970-01-01T00:00:00 (not fixed to any specific time zone).
054     * <p>
055     * This method is useful in certain circustances for high performance
056     * access to the datetime fields.
057     * 
058     * @return the number of milliseconds since 1970-01-01T00:00:00
059     */
060    protected abstract long getLocalMillis();
061
062}