title: Got java "Unsupported major.minor version 52.0" when installing Hadoop on AWS
body: <p>I am following these videos to install Hadoop on AWS EC2:
  <a href="https://www.youtube.com/watch?v=cr5RmnyWbYw" rel="nofollow noreferrer">https://www.youtube.com/watch?v=cr5RmnyWbYw</a></p>
  
  <p>But got this poblem with very end steps:</p>
  
  <p>$HADOOP_HOME/sbin/start-dfs.sh</p>
  
  <p>Exception in thread "main" java.lang.UnsupportedClassVersionError: org/apache/hadoop/mapreduce/lib/output/SequenceFileAsBinaryOutputFormat : U                                                                                               nsupported major.minor version 52.0</p>
  
  <p>I did some search and was told this is because the java version not match. I tried to install java-sdk-8 but not help.</p>
  
  <p>The ubuntu system I used is 14.04, and this is the java version information:
  ~$ java -version
  java version "1.7.0_151"
  OpenJDK Runtime Environment (IcedTea 2.6.11) (7u151-2.6.11-0ubuntu1.14.04.1)
  OpenJDK 64-Bit Server VM (build 24.151-b01, mixed mode)</p>
  
  <p>Any suggestion will be appreciated~~</p>