Install Java for Openhab2

i have installed a new debian installation (64bit) with latest debian 8 version.

Now i installed Java 8 with this how-to

Oracle Java 8 from webupd8 servers.

Now i get this outpoot:

root@debian:/# java -version
java version "1.8.0_121"
Java(TM) SE Runtime Environment (build 1.8.0_121-b13)
Java HotSpot(TM) 64-Bit Server VM (build 25.121-b13, mixed mode)

Is this the right java version for OH2? Or is this 64bit version and i have to install 32bit version?

What do i have to do if i have the wrong version installed?

Yes, it’s fine for OH2.

You have installed the 64-bit version of Java JDK 8 (Java Development Kit), which includes JRE (Java Runtime Environment).

The latest recommendation from the openHAB team is to use Zulu (see: but Oracle JDK 8 update 101 and above should be fine.

The 32-bit version of Java is recommended for ARM systems running a 64-bit O/S to get the serial connections to work.
This limitation does not apply to regular x64 systems

You can always switch by:

update-alternatives --config java

Hm, few days ago i looked into the openhab manual and there was nothing written with zulu… Oracle Java was the recommended version.

But if it´s working with this oracle java too, than no reason to switch.

Thank you.

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