hadoop on ubunte with java 8

1, install java 8
 sudo add-apt-repository ppa:webupd8team/java
 sudo apt-get update
 sudo apt-get install oracle-java8-installer

2, export java

export JAVA_HOME=/usr/lib/jvm/java-8-oracle/

3, download hadoop

wget http://apache.arvixe.com/hadoop/common/stable/hadoop-2.7.1.tar.gz

4, copy xml file

cp hadoop-2.7.1/etc/hadoop/*.xml input/

5, run hadoop

hadoop-2.7.1/bin/hadoop jar hadoop-2.7.1/share/hadoop/mapreduce/hadoop-mapreduce-examples-2.7.1.jar grep input output 'dfs[a-z.]+'