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Implementation of a client to the Astra/Stargate Data API written in Java

There is a newer version: 1.5.3

package com.datastax.astra.client.model;

/*-
 * #%L
 * Data API Java Client
 * --
 * Copyright (C) 2024 DataStax
 * --
 * Licensed under the Apache License, Version 2.0
 * You may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *   http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 * #L%
 */

import java.util.Arrays;

/**
 * Encode the presence of a field in the result.
 */
public class Projections {

    /**
     * Hide constructor
     */
    private Projections() {}

    /**
     * Include a field in the result.
     *
     * @param field
     *      include field
     * @return
     *      name to include
     */
    public static Projection[] include(String... field) {
        return Arrays.stream(field)
                .map(f -> new Projection(f, true, null, null))
                .toArray(Projection[]::new);
    }

    /**
     * Specifies the number of elements in an array to return in the query result.
     *      * {@code
     * // Return the first two elements
     * { $slice: 2 }
     *
     * // Return the last two elements
     * { $slice: -2 }
     *
     * // Skip 4 elements (from 0th index), return the next 2
     * { $slice: [4, 2] }
     *
     * // Skip backward 4 elements, return next 2 elements (forward)
     * { $slice: [-4, 2] }
     * }
     * 
     *
     * @param field
     *      field name for slice
     * @param start
     *      start index of slice
     * @param end
     *     end index of slice
     * @return
     *      a projection for the slide
     */
    public static Projection slice(String field, Integer start, Integer end) {
        return new Projection(field, null, start, end);
    }

    /**
     * Exclude  a field in the result.
     *
     * @param field
     *      field name to exclude
     * @return
     *      list of projection
     */
    public static Projection[] exclude(String... field) {
        return Arrays.stream(field)
                .map(f -> new Projection(f, false, null, null))
                .toArray(Projection[]::new);
    }
}