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Object Oriented Wrapper of Amazon DynamoDB SDK
There is a newer version: 0.22.4
/**
 * Copyright (c) 2012-2017, jcabi.com
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met: 1) Redistributions of source code must retain the above
 * copyright notice, this list of conditions and the following
 * disclaimer. 2) Redistributions in binary form must reproduce the above
 * copyright notice, this list of conditions and the following
 * disclaimer in the documentation and/or other materials provided
 * with the distribution. 3) Neither the name of the jcabi.com nor
 * the names of its contributors may be used to endorse or promote
 * products derived from this software without specific prior written
 * permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT
 * NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
 * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
 * THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 * OF THE POSSIBILITY OF SUCH DAMAGE.
 */
package com.jcabi.dynamo;

import com.amazonaws.services.dynamodbv2.model.AttributeValue;
import com.jcabi.aspects.Immutable;
import com.jcabi.aspects.Loggable;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import lombok.EqualsAndHashCode;
import lombok.ToString;

/**
 * Dosage of items retrieved from table.
 *
 * @author Yegor Bugayenko ([email protected])
 * @version $Id: 34e6623c3c482571ca0f61e206ce4b942cd7e51c $
 * @since 0.1
 */
@Immutable
public interface Dosage {

    /**
     * Items.
     * @return List of items
     */
    List> items();

    /**
     * Has next dosage?
     * @return TRUE if next storage is avaiable
     */
    boolean hasNext();

    /**
     * Fetch next dosage.
     * @return The dosage
     */
    Dosage next();

    /**
     * Always empty.
     */
    @Immutable
    @Loggable(Loggable.DEBUG)
    @ToString
    @EqualsAndHashCode
    final class Empty implements Dosage {
        @Override
        public List> items() {
            return new ArrayList>(0);
        }
        @Override
        public Dosage next() {
            throw new IllegalStateException(
                "this is nothing left"
            );
        }
        @Override
        public boolean hasNext() {
            return false;
        }
    }

}