title: Running Hadoop Pi Example
body: <p>I need some help running Hadoop Pi example in Windows. I have sucecssfully setup Hadoop on Windows and can see all NameNode, SecondaryNameNode, JobTracker and TaskTracker running. I can also hit urls: </p>
  
  <pre><code>http://localhost:50070/, http://localhost:50030 and http://localhost:50090/.
  </code></pre>
  
  <p>However when I am trying to run the in-built Pi example I am getting following exception. </p>
  
  <pre><code>$ hadoop jar hadoop/hadoop-examples-1.2.1.jar pi 4 100
  Not a valid JAR: C:\cygwin\home\chandeln\hadoop\hadoop-examples-1.2.1.jar
  </code></pre>
  
  <p>I have also set both hadoop and java in my path.</p>
  
  <pre><code>$ java -version
  java version "1.7.0_40"
  Java(TM) SE Runtime Environment (build 1.7.0_40-b43)
  Java HotSpot(TM) 64-Bit Server VM (build 24.0-b56, mixed mode)
  
  $ hadoop version
  Hadoop 1.2.1
  Subversion https://svn.apache.org/repos/asf/hadoop/common/branches/branch-1.2 -r 1503152
  Compiled by mattf on Mon Jul 22 15:23:09 PDT 2013
  From source with checksum 6923c86528809c4e7e6f493b6b413a9a
  This command was run using /C:/cygwin/usr/local/hadoop/hadoop-core-1.2.1.jar
  </code></pre>
  
  <p>My .bashrc looks like this:</p>
  
  <pre><code>export JAVA_HOME=/cygdrive/c/Java/jdk1.7.0_40
  export HADOOP_PREFIX=/cygdrive/c/usr/local/hadoop
  export PATH=$PATH:$HADOOP_PREFIX/bin
  </code></pre>
  
  <p>Can anybody shed some light on this ?</p>