C# Hadoop学习笔记（一）—环境安装

一、安装环境

1，前期准备：官网下载“NuGet Package Manager”，按自己已有的VS环境下载对应版本；

2，利用NuGet下载Hadoop For .NET SDK,地址“http://hadoopsdk.codeplex.com/”

3，安装。

4，通过HDInsight，安装Windows Azure，目前是预览版本。

5，参照网址“http://blogs.msdn.com/b/data_otaku/archive/2013/08/14/hadoop-for-net-developers.aspx” 系统学习API

 

二、测试DEMO

 

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using Microsoft.Hadoop;
using Microsoft.Hadoop.MapReduce;
using Microsoft.Hadoop.WebClient.WebHCatClient;
using System.Diagnostics;
using System.IO;
using System.IO.MemoryMappedFiles;


namespace HadoopConsol
{
    class Program
    {
        static void Main(string[] args)
        {
            Stopwatch sw = new Stopwatch();
            long hadoopTime=0;
            long normalTime=0;

            sw.Start();

            //start hadoop
            Console.WriteLine("     Hadoop Process Strating ....");

            #region Hadoop time

            #region hadoopconnet

            Console.WriteLine("     Hadoop Connect Strating ....");

            //establish job configuration

            HadoopJobConfiguration myConfig = new HadoopJobConfiguration();

            myConfig.InputPath = "/demo/simple/in";

            myConfig.OutputFolder = "/demo/simple/out";



            //connect to cluster

            Uri myUri = new Uri("http://localhost");

            string userName = "hadoop";

            string passWord = null;

            IHadoop myCluster = Hadoop.Connect(myUri, userName, passWord);

            hadoopTime += sw.ElapsedMilliseconds;

            Console.WriteLine("     Hadoop Connect End.");

            Console.WriteLine("     Hadoop Connect time:" + sw.ElapsedMilliseconds);

            #endregion


            #region hadoopmapreduce

            sw.Reset();
            sw.Start();

            Console.WriteLine("     Hadoop MapReduce Strating ....");

            //execute mapreduce job

            MapReduceResult jobResult =

                myCluster.MapReduceJob.Execute(myConfig);

            hadoopTime += sw.ElapsedMilliseconds;

            Console.WriteLine("     Hadoop MapReduce End.");
            Console.WriteLine("     Hadoop MapReduce Time:"+sw.ElapsedMilliseconds);

            #endregion

            #region Hadoop End

            sw.Reset();
            sw.Start();

            Console.WriteLine("     Hadoop Endprocess Strating ....");

            //write job result to console

            int exitCode = jobResult.Info.ExitCode;



            string exitStatus = "Failure";

            if (exitCode == 0) exitStatus = "Success";

            exitStatus = exitCode + " (" + exitStatus + ")";

            Console.WriteLine();

            Console.Write("Exit Code = " + exitStatus);

            Console.WriteLine("     Hadoop Endprocess End.");
            hadoopTime += sw.ElapsedMilliseconds;
            Console.WriteLine("     Hadoop Exit Time:" + sw.ElapsedMilliseconds);
            Console.WriteLine("     Hadoop Process All Time:" + hadoopTime);
            #endregion

            #endregion


            #region Normal time
            //start Normal
            Console.WriteLine("     Normal Process Strating ....");

            sw.Reset();
            sw.Start();

            //normal process
            #region Normal Process

            int myevenCount = 0;
            int myeventSum = 0;

            int myoddCount = 0;
            int myoddSum = 0;

            StreamReader fs = new StreamReader(@"c:\TEMP\integers.txt");

            while (fs.Peek() >= 0)
            {
                string strTemp = fs.ReadLine();
                if (Int32.Parse(strTemp) % 2 == 0)
                {
                    myevenCount++;
                    myeventSum += Int32.Parse(strTemp);
                }
                else
                {
                    myoddCount++;
                    myoddSum += Int32.Parse(strTemp);
                }
            }
               //MemoryMappedFile m = MemoryMappedFile.
            Console.WriteLine("even:" + "\t" + myevenCount + "\t" + myeventSum);
            Console.WriteLine("odd:" + "\t" + myoddCount + "\t" + myoddSum);

            #endregion

            Console.WriteLine("     Normal Process End.");

            normalTime += sw.ElapsedMilliseconds;
            Console.WriteLine("     Normal Exit Time:" + sw.ElapsedMilliseconds);
            Console.WriteLine("     Normal Process All Time:" + normalTime);

            #endregion

            sw.Stop();

            Console.Read();

        }

    }

    public class MySimpleMapper : MapperBase
    {

        public override void Map(string inputLine, MapperContext context)
        {

            //interpret the incoming line as an integer value

            int value = int.Parse(inputLine);

            //determine whether value is even or odd

            string key = (value % 2 == 0) ? "even" : "odd";

            //output key assignment with value

            context.EmitKeyValue(key, value.ToString());

        }

    }

    public class MySimpleReducer : ReducerCombinerBase
    {

        public override void Reduce(

            string key, IEnumerable values, ReducerCombinerContext context

            )
        {

            //initialize counters

            int myCount = 0;

            int mySum = 0;



            //count and sum incoming values

            foreach (string value in values)
            {

                mySum += int.Parse(value);

                myCount++;

            }



            //output results

            context.EmitKeyValue(key, myCount + "\t" + mySum);

        }


    }
}

三、测试结果