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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
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 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
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package java.util.function;

/**
 * An operation on a single {@code long} operand yielding a {@code long} result.
 *
 * <p>This is the primitive type specialization of {@link UnaryOperator} for
 * {@code long} and also may be used as a {@code UnaryOperator<Long>}. When
 * used as a {@code UnaryOperator} the default {@code operate} implementation
 * provided by this interface neither accepts null parameters nor does it return
 * null results.
 *
 * @since 1.8
 */
public interface LongUnaryOperator extends UnaryOperator<Long> {

    /**
     * {@inheritDoc}
     *
     * @param operand {@inheritDoc}, must be non-null
     * @return {@inheritDoc}, always non-null
     */
    @Override
    public default Long operate(Long operand) {
        return operateAsLong((long)operand);
    }

    /**
     * Returns the {@code long} result of the operation upon the {@code long}
     * operand.
     *
     * @param operand the operand value
     * @return the operation result value
     */
    public long operateAsLong(long operand);
}