Windows7作業系統下使用Eclipse來搭建hadoop開發環境
[main] WARN org.apache.hadoop.util.NativeCodeLoader- Unable to load native-hadoop library for your platform... using builtin-javaclasses where applicable
[main] INFOorg.apache.hadoop.conf.Configuration.deprecation - session.id is deprecated.Instead, use dfs.metrics.session-id
[main] INFOorg.apache.hadoop.metrics.jvm.JvmMetrics - Initializing JVM Metrics withprocessName=JobTracker, sessionId=
[main] WARNorg.apache.hadoop.mapreduce.JobResourceUploader - No job jar file set. User classes may not be found. See Job orJob#setJar(String).
[main] INFOorg.apache.hadoop.mapreduce.lib.input.FileInputFormat - Total input paths toprocess : 1
[main] INFOorg.apache.hadoop.mapreduce.JobSubmitter - number of splits:1
[main] INFOorg.apache.hadoop.mapreduce.JobSubmitter - Submitting tokens for job:job_local1072922152_0001
[main] INFOorg.apache.hadoop.mapreduce.JobSubmitter - Cleaning up the staging areafile:/tmp/hadoop-Cyril/mapred/staging/Cyril1072922152/.staging/job_local1072922152_0001
Exception in thread "main"java.lang.UnsatisfiedLinkError:org.apache.hadoop.io.nativeio.NativeIO$Windows.access0(Ljava/lang/String;I)Z
atorg.apache.hadoop.io.nativeio.NativeIO$Windows.access0(Native Method)
atorg.apache.hadoop.io.nativeio.NativeIO$Windows.access(NativeIO.java:609)
atorg.apache.hadoop.fs.FileUtil.canRead(FileUtil.java:977)
atorg.apache.hadoop.util.DiskChecker.checkAccessByFileMethods(DiskChecker.java:187)
atorg.apache.hadoop.util.DiskChecker.checkDirAccess(DiskChecker.java:174)
atorg.apache.hadoop.util.DiskChecker.checkDir(DiskChecker.java:108)
atorg.apache.hadoop.fs.LocalDirAllocator$AllocatorPerContext.confChanged(LocalDirAllocator.java:285)
atorg.apache.hadoop.fs.LocalDirAllocator$AllocatorPerContext.getLocalPathForWrite(LocalDirAllocator.java:344)
atorg.apache.hadoop.fs.LocalDirAllocator.getLocalPathForWrite(LocalDirAllocator.java:150)
atorg.apache.hadoop.fs.LocalDirAllocator.getLocalPathForWrite(LocalDirAllocator.java:131)
atorg.apache.hadoop.fs.LocalDirAllocator.getLocalPathForWrite(LocalDirAllocator.java:115)
atorg.apache.hadoop.mapred.LocalDistributedCacheManager.setup(LocalDistributedCacheManager.java:125)
atorg.apache.hadoop.mapred.LocalJobRunner$Job.<init>(LocalJobRunner.java:163)
atorg.apache.hadoop.mapred.LocalJobRunner.submitJob(LocalJobRunner.java:731)
atorg.apache.hadoop.mapreduce.JobSubmitter.submitJobInternal(JobSubmitter.java:240)
atorg.apache.hadoop.mapreduce.Job$10.run(Job.java:1290)
atorg.apache.hadoop.mapreduce.Job$10.run(Job.java:1287)
atjava.security.AccessController.doPrivileged(Native Method)
atjavax.security.auth.Subject.doAs(Unknown Source)
atorg.apache.hadoop.security.UserGroupInformation.doAs(UserGroupInformation.java:1698)
atorg.apache.hadoop.mapreduce.Job.submit(Job.java:1287)
atorg.apache.hadoop.mapreduce.Job.waitForCompletion(Job.java:1308)
atWordCount.main(WordCount.java:61)
可能原因：
1、[main] WARNorg.apache.hadoop.util.NativeCodeLoader - Unable to load native-hadoop libraryfor your platform... using builtin-java classes where applicable，由這條日誌資訊表明缺少hadoop動態庫（Hadoop.dll）
解決辦法：
在網上下載hadoop.dll，將其拷貝到c:\windows\System32\資料夾下即可。
12、程式打包
右鍵單擊工程，點開“Export…”在彈出的對話方塊中選擇“JAR file”，如下圖：
點選“Next”，彈出如下對話方塊。
勾選如圖所示選項，單擊“Browse”新增“JAR file”的輸出路徑，然後單擊“Next”按鈕，彈出如下對話方塊：
單擊“Next”，彈出如下對話方塊：
單擊“Browse”按鈕新增Main class，如下圖所示：
單擊“OK”
單擊“Finish”。
將生成的“WordCount.jar”檔案上傳到叢集的“/srv/ftp”目錄下，然後通過以下命令執行程式：
hadoopjar /srv/ftp/WordCount.jar /input /output