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I have followed all the instructions stated at this question, but am encountering some problems with the last part of it.

I actually have version 6.22 of java and would like to update to version 6.30.

So after moving the extracted directory java-6-oracle into /usr/lib/jvm I do not know what to do, since the script that is pointed out in the answer above updates from java 5 to java 6.

For sake of clearness here is output if I do an ls in dir /usr/lib/jvm:

matteo@matteo-ThinkPad-SL:/usr/lib/jvm$ ls -l

total 8

lrwxrwxrwx 1 root root 14 2011-07-12 15:18 default-java -> java-6-openjdk

lrwxrwxrwx 1 root root 14 2011-07-12 12:19 java-1.6.0-openjdk -> java-6-openjdk

drwxr-xr-x 10 root root 4096 2012-04-12 12:06 java-6.31-oracle

drwxr-xr-x 7 root root 4096 2012-02-24 14:43 java-6-openjdk

What should I do now?


Under the suggestion of @fossfreedom I ran the script anyway and actually it updated the java version.

Infact if I run command java -version outpu will be the following:

matteo@matteo-ThinkPad-SL:~$ java -version
java version "1.6.0_31"
Java(TM) SE Runtime Environment (build 1.6.0_31-b04)
Java HotSpot(TM) Server VM (build 20.6-b01, mixed mode)

There is still a problem, if Irun javac -version it gives me the old version installed:

matteo@matteo-ThinkPad-SL:~$ javac -version
javac 1.6.0_22

And if I use the tester at this link it will tell me that version is

Java Version 1.6.0_22 from Sun Microsystems Inc.

What's going wrong?

It seems that Java Runtime Environment has updated, but Java Compiler and Java plugin for browser have not.

How can I update them?


sudo update-alternatives --config java will return following output

matteo@matteo-ThinkPad-SL:~$ sudo update-alternatives --config java
There are 2 choices for the alternative java (providing /usr/bin/java).

  Selection    Path                                      Priority   Status
* 0            /usr/lib/jvm/java-6.31-oracle/bin/java     1062      auto mode
  1            /usr/lib/jvm/java-6-openjdk/jre/bin/java   1061      manual mode
  2            /usr/lib/jvm/java-6.31-oracle/bin/java     1062      manual mode

Press enter to keep the current choice[*], or type selection number:

these makes sense with the fact that JRE is correctly updated to version 6.31, issues are on Java Compiler and Java browser plugin.

Any ideas?

share|improve this question
... are you talking about the webupd8 script? What do you see when you run the script? –  fossfreedom Apr 13 '12 at 11:08
@fossfreedom I haven't tried it cause I thought it wasn't a good idea being it explicitely written for uploading from Java 5 to 6, should I anyway? –  Matteo Apr 13 '12 at 12:01
hmmm - possibly you may be confusing that the webupd8 script is 0.5b? That is the version of the script - it doesnt refer to the java version. Give it a try. Lets see a screenshot of what the window looks like when you run the script. –  fossfreedom Apr 13 '12 at 12:13
@fossfreedom yeah that totally confused me ;D I ran the script! check the edits in question!thks a lot for helping me.. –  Matteo Apr 13 '12 at 12:16
how very strange ... never encountered that. Anyway - look at the answer just below - you should be able to sudo update-alternatives as per the example. –  fossfreedom Apr 13 '12 at 12:20

2 Answers 2

up vote 23 down vote accepted

Re your first question:

possibly you may be confusing that the webupd8 script is 0.5b. That is the version of the script - it doesnt refer to the java version.

Further to the setting of the javac version.

I suspect you need to explicitly give the path of the javac compiler


sudo update-alternatives --install "/usr/bin/javac" "javac" "/usr/lib/jvm/java-6.31-oracle/bin/javac" 1

followed by:

sudo update-alternatives --config javac

With regards to setting up the java chrome plugin.

The master question:

How do I install Oracle's JDK 6?

includes this information - since your folder structure is slightly different your link command should be:

ln -s /usr/lib/jvm/java-6.31-oracle/jre/lib/i386/libnpjp2.so ~/.mozilla/plugins/
share|improve this answer
On its own this just changes the compiler - see the answer below for update-java-alternatives which handles switching all of the java-related alternatives, which is 82 on my system. –  Greg May 10 '14 at 10:16

I think you should take a look at the update-java-alternatives command from the java-common package and the *.jinfo files used by it. With that you should be able to switch completely between java installations (regardless of JDK, JRE, ...).

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