lang/cs/Org.Apache.REEF.IMRU.Examples/MapperCount/MapperCountUpdateFunction.cs

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//   http://www.apache.org/licenses/LICENSE-2.0
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using Org.Apache.REEF.IMRU.API;
using Org.Apache.REEF.Tang.Annotations;

namespace Org.Apache.REEF.IMRU.Examples.MapperCount
{
    /// <summary>
    /// The Update function for the mapper counting job.
    /// </summary>
    /// <remarks>
    /// Upon Initialize(), this sends `1` to all Map Function instances. Each of them returns `1`, which shows up as the
    /// parameter passed into `Update`. At that point, we can immediately terminate.
    /// </remarks>
    public sealed class MapperCountUpdateFunction : IUpdateFunction<int, int, int>
    {
        [Inject]
        private MapperCountUpdateFunction()
        {
        }

        /// <summary>
        /// Update function
        /// </summary>
        /// <param name="input">Input containing sum of all mappers</param>
        /// <returns>The Update Result with only result</returns>
        public UpdateResult<int, int> Update(int input)
        {
            return UpdateResult<int, int>.Done(input);
        }

        /// <summary>
        /// Initialize function. Sends 1 to all mappers
        /// </summary>
        /// <returns>Map input</returns>
        public UpdateResult<int, int> Initialize()
        {
            return UpdateResult<int, int>.AnotherRound(1);
        }
    }
}