There are 3 choices for the alternative java (providing /usr/bin/java).

  Selection    Path                                     Priority   Status
------------------------------------------------------------
* 0            /usr/lib/jvm/java-7-oracle/jre/bin/java   6         auto mode
  1            /usr/lib/jvm/java-6-oracle/jre/bin/java   2         manual mode
  2            /usr/lib/jvm/java-7-oracle/jre/bin/java   6         manual mode
  3            /usr/lib/jvm/java-8-oracle/jre/bin/java   5         manual mode