How to check Java version on Lubuntu

If you have java (JDK or JRE) installed on your system but you are not sure what version of java you currently have, you can run this command to check your java version.

Open your terminal/ console/ command line prompt (press CTRL + ALT + T) and then execute the command below:

java -version

Here's the results from my computer:

kernelpanic@kernelpanic:~$ java -version
java version "1.7.0_95"
OpenJDK Runtime Environment (IcedTea 2.6.4) (7u95-2.6.4-0ubuntu0.15.10.1)
OpenJDK 64-Bit Server VM (build 24.95-b01, mixed mode)

So basically what i have is open JDK version 7 based on the result above, yours might be different, maybe you are using oracle JDK instead of open JDK, that's ok.