安装Hadoop 和 Hive

Hadoop是依赖于Java，所以安装Hadoop之前，我们需要先安装Java。
可以通过这个命令查看Java的版本：

~$ java -version

Command 'java' not found, but can be installed with:

sudo apt install default-jre            
sudo apt install openjdk-11-jre-headless
sudo apt install openjdk-8-jre-headless 
sudo apt install openjdk-9-jre-headless 

在发现未安装Java之后，我们可以通过如下代码安装Java：

~$ sudo apt-get install default-jre
~$ sudo apt-get install default-jdk
~$ sudo add-apt-repository ppa:webupd8team/java
~$ sudo apt-get update
#Java8
~$ sudo apt-get install oracle-java8-installer
~$ sudo apt-get install oracle-java8-set-default
#设置环境变量
~$ export JAVA_HOME=/usr/lib/jvm/java-8-oracle
~$ source ~/.bashrc
~$ java -version

java version "1.8.0_181"
Java(TM) SE Runtime Environment (build 1.8.0_181-b13)
Java HotSpot(TM) 64-Bit Server VM (build 25.181-b13, mixed mode)

下面是下载安装Hadoop,选择的是2.9.1版本：

~$ wget http://www.us.apache.org/dist/hadoop/common/hadoop-2.9.1/hadoop-2.9.1.tar.gz
~$ tar -xzf hadoop-2.9.1.tar.gz
~$ sudo echo "export HADOOP_HOME=$PWD/hadoop-2.9.1"
~$ sudo echo "export HADOOP_HOME=$PWD/hadoop-2.9.1" > /etc/profile.d/hadoop.sh
~$ sudo echo "PATH=$PATH:$HADOOP_HOME/bin" > /etc/profile.d/hadoop.sh
~$ . /etc/profile

#test
~$ hadoop dfs -ls /
DEPRECATED: Use of this script to execute hdfs command is deprecated.
Instead use the hdfs command for it.

Found 26 items
drwxr-xr-x   - root root       4096 2018-07-29 18:13 /bin
drwxr-xr-x   - root root       4096 2018-07-29 18:14 /boot
drwxrwxr-x   - root root       4096 2018-07-29 17:49 /cdrom
drwxr-xr-x   - root root       3860 2018-07-29 18:26 /dev
drwxr-xr-x   - root root      12288 2018-07-29 19:11 /etc
drwxr-xr-x   - root root       4096 2018-07-29 17:53 /home
...

最后就是安装Hive了：

~$ wget http://archive.apache.org/dist/hive/hive-2.3.3/apache-hive-2.3.3-bin.tar.gz
~$ tar -xzf apache-hive-2.3.3-bin.tar.gz
~$ sudo mkdir -p /user/hive/warehouse
~$ sudo chmod a+rwx /user/hive/warehouse
#设置环境变量