How to know if I am using Open JDK or Oracle JDK?

Question

Using java -version gives me this.

java version "1.7.0_80" Java(TM) SE Runtime Environment (build 1.7.0_80-b15) Java HotSpot(TM) 64-Bit Server VM (build 24.80-b11, mixed mode) 

Is it an OpenJDK or OracleJDK ?

Answer 1

I think that you're using OracleJDK.

As I saw with a google search, the openJDK --version output is like this:

java -version

openjdk version "1.8.0-internal"

OpenJDK Runtime Environment (build 1.8.0-internal-0)

OpenJDK 64-Bit Zero VM (build 25.0-b20-internal, interpreted mode)

See: http://mail.openjdk.java.net/pipermail/jdk8-dev/2013-July/002840.html

Answer 2

On debian, jessie-backports, openjdk-8:

openjdk version "1.8.0_66-internal" OpenJDK Runtime Environment (build 1.8.0_66-internal-b17) OpenJDK 64-Bit Server VM (build 25.66-b17, mixed mode) 

Using the ubuntu ppa for oracle-java-8:

java version "1.8.0_66" Java(TM) SE Runtime Environment (build 1.8.0_66-b17) Java HotSpot(TM) 64-Bit Server VM (build 25.66-b17, mixed mode) 

I would assume, the string "java" at the beginning denotes Oracle Java, whereas the OpenJDK gets you "openjdk".