Java 8 vs. Java 1.8 installation (directory name)

Choose Java version:

sudo update-alternatives --config java

Example output:

There are 2 choices for the alternative java (providing usr/bin/java).         
Selection     Path                                            Priority  Status
------------------------------------------------------------
  0           /usr/lib/jvm/java-8-oracle/jre/bin/java          1081     auto mode
  1           /usr/lib/jvm/java-8-openjdk-amd64/jre/bin/java   1081     manual mode
* 2           /usr/lib/jvm/java-8-oracle/jre/bin/java          1081     manual mode

Press <enter> to keep the current choice[*], or type selection number: 

You may also see the alternatives for java, javac by using the --list option:

sudo update-alternatives --list java
sudo update-alternatives --list javac