001/*
002 * (C) Copyright 2014 Nuxeo SA (http://nuxeo.com/) and others.
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 *
016 * Contributors:
017 *     Florent Guillaume
018 */
019package org.nuxeo.ecm.core.api.model;
020
021/**
022 * Value holding a base value and a delta.
023 * <p>
024 * This is used when the actual intent of the value is to be an incremental update to an existing value.
025 *
026 * @since 6.0
027 */
028public abstract class Delta extends Number {
029
030    private static final long serialVersionUID = 1L;
031
032    /**
033     * Gets the full value (base + delta) as an object.
034     *
035     * @return the full value
036     */
037    public abstract Number getFullValue();
038
039    /**
040     * Gets the delta value as an object.
041     *
042     * @return the delta value
043     */
044    public abstract Number getDeltaValue();
045
046    /**
047     * Gets the base value.
048     *
049     * @return the base value
050     * @since 8.3
051     */
052    public abstract Number getBase();
053
054    /**
055     * Adds this delta to another delta.
056     *
057     * @param other the other delta
058     * @return the added delta
059     */
060    public abstract Delta add(Delta other);
061
062    /**
063     * Adds this delta to a number.
064     *
065     * @param other the number
066     * @return the resulting number
067     */
068    public abstract Number add(Number other);
069
070    // make these two abstract to force implementation
071
072    @Override
073    public abstract boolean equals(Object obj);
074
075    @Override
076    public abstract int hashCode();
077
078}