001/*
002 * ============================================================================
003 * Copyright © 2002-2020 by Thomas Thrien.
004 * All Rights Reserved.
005 * ============================================================================
006 *
007 * Licensed to the public under the agreements of the GNU Lesser General Public
008 * License, version 3.0 (the "License"). You may obtain a copy of the License at
009 *
010 *      http://www.gnu.org/licenses/lgpl.html
011 *
012 * Unless required by applicable law or agreed to in writing, software
013 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
014 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
015 * License for the specific language governing permissions and limitations
016 * under the License.
017 */
018
019package org.tquadrat.foundation.function;
020
021import static org.apiguardian.api.API.Status.STABLE;
022
023import java.util.function.Supplier;
024
025import org.apiguardian.api.API;
026import org.tquadrat.foundation.annotation.ClassVersion;
027
028/**
029 *  <p>{@summary Represents a supplier of
030 *  {@link Number}-valued
031 *  results.} This is the {@code Number}-producing specialisation of
032 *  {@link java.util.function.Supplier}.</p>
033 *  <p>There is no requirement that a distinct result is returned each time the
034 *  supplier is invoked.</p>
035 *  <p>This is a
036 *  {@linkplain java.lang.FunctionalInterface functional interface}
037 *  whose functional method is
038 *  {@link #getAsNumber()}.</p>
039 *
040 *  @see java.util.function.Supplier
041 *
042 *  @extauthor Thomas Thrien - thomas.thrien@tquadrat.org
043 *  @version $Id: NumberSupplier.java 993 2022-01-19 22:26:20Z tquadrat $
044 *  @since 0.0.5
045 *
046 *  @UMLGraph.link
047 */
048@ClassVersion( sourceVersion = "$Id: NumberSupplier.java 993 2022-01-19 22:26:20Z tquadrat $" )
049@FunctionalInterface
050@API( status = STABLE, since = "0.0.5" )
051public interface NumberSupplier extends Supplier<Number>
052{
053        /*---------*\
054    ====** Methods **==========================================================
055        \*---------*/
056    /**
057     *  {@inheritDoc}
058     */
059    @Override
060    public default Number get() { return getAsNumber(); }
061
062    /**
063     *  Gets a result.
064     *
065     *  @return The result; may be {@code null}.
066     */
067    public Number getAsNumber();
068}
069//  interface NumberSupplier
070
071/*
072 *  End of File
073 */