Updating Java x64 through command line? Lag spike question too.

I've been looking through the bukkit forums but I haven't found a way to update my Java through terminal (I run Ubuntu server edition). When I type java -version I get:

java version "1.6.0_26"
Java(TM) SE Runtime Environment (build 1.6.0_26-b03)
Java HotSpot(TM) 64-Bit Server VM (build 20.1-b02, mixed mode)

Is my Java up-to-date? I've been having a lot of "end of stream", "socket closed" and "[Warning] Can't keep up!" errors (even at 20/20 tps lag and 80% memory free (I have 6gb allocated), and I thought that updating Java might solve my problems.

Could someone give me a code snippet that I could put in that would easily update Java for me? Also, I heard that I need to set that java as the default java to use? (in another thread) How can I make sure that I did that?

Here's my serverstart.sh file in case it helps:
java -Xincgc -Xmx6G -jar /home/charles/Bukkit/craftbukkit-0.0.1-SNAPSHOT.jar

PS The lag I get on my server is very strange.. It isn't typical lag. I have lagmeter installed and almost always I have 20/20 tps lag and over 60% memory free. The lag is kind of a short freeze, and happens about once every 15 minutes (at different times at different frequencies for different players). Then, they often will get a "socket closed" error and leave the server, always accompanied by the same [SEVERE] error message and "read timed out" on the console.

I have 30/10Mbps Internet, upgrading to 200/200M on Saturday. Maybe it's a bandwidth bottleneck?

I was reading this topic (http://forums.bukkit.org/threads/bukkit-server-random-lag.21548/) and the lag problem seemed kind of similar to mine. Apparently he fixed the problem by switching to a better (wired) connection.
However I also read that his AMD Athlon might have been causing the problem. I have an AMD II X4 630 processor. Could that be contributing to the strange socket closed errors? Maybe I'm port forwarding wrong? (I'm pretty sure I did it right though)

EDIT by Moderator: merged posts, please use the edit button instead of double posting.

 

Try apt-get upgrade. That might work because that is supposed to upgrade all packages. In the Ubuntu packages, it says that java-common supports all architectures. I don't have an answer to your other question.

Also see: http://aruljohn.com/info/apt/

EDIT by Moderator: merged posts, please use the edit button instead of double posting.

 

Thanks for the help. I know apt get and apt update, but I was wondering what the command would be to update the right version of Java for CraftBukkit 1060. Hopefully that's the one I have!

 

I am running 1.7. You are welcome.