Unable to install Java 6 and install 7

Question

I am trying to install Java 7. I tested my Java version first, please see the below code

ubuadmin@ubuserver3:~/JavaJars/HelloWordGPU$ java -version
java version "1.6.0_30"
OpenJDK Runtime Environment (IcedTea6 1.13.1) (6b30-1.13.1-1ubuntu2~0.12.04.1)
OpenJDK Client VM (build 23.25-b01, mixed mode, sharing)

I tried uninstalling this first, using below command:

sudo apt-get remove openjdk-6-jdk

It gave me the following result.

ubuadmin@ubuserver3:~/JavaJars/HelloWordGPU$ sudo apt-get remove openjdk-6-jdk
Reading package lists... Done
Building dependency tree
Reading state information... Done
Package openjdk-6-jdk is not installed, so not removed
0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
ubuadmin@ubuserver3:~/JavaJars/HelloWordGPU$

I also tried using sudo apt-get remove default-jdk but same.

So how can I install Java 7?

@ElliottFrisch: I tried google. I visited http://stackoverflow.com/questions/20690143/java-unsupported-major-minor-version-51-0, http://askubuntu.com/questions/139702/completely-uninstall-and-reinstall-openjdk, and http://askubuntu.com/questions/84483/how-to-completely-uninstall-java. That is why I came here. — PeakGen, Mar 12 '14 at 04:47

score 1 · Answer 1 · answered Mar 12 '14 at 04:47

1

From the directions posted here,

sudo add-apt-repository ppa:webupd8team/java
sudo apt-get update
sudo apt-get install oracle-java7-installer

Then you can use update-java-alternatives,

sudo update-java-alternatives -l
sudo update-java-alternatives -s <The correct Java 7 JDK>

answered Mar 12 '14 at 04:47

Elliott Frisch

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Hello, Thanks for the reply. Why 90% of the user use `OpenJDK` in Ubuntu? Even in that link says "if you `really` want to install oracle"... – PeakGen Mar 12 '14 at 04:50
Because the Oracle JVM is not open source. – Elliott Frisch Mar 12 '14 at 04:53
For the first command, it says `sudo: add-apt-repository: command not found ` – PeakGen Mar 12 '14 at 05:15
`sudo apt-get install python-software-properties` – Elliott Frisch Mar 12 '14 at 05:17

Lee Duhem · Answer 2 · 2014-03-12T05:35:46.797

1

You could install openjdk-7-jdk directly by

apt-get install openjdk-7-jdk

After that, you could use update-java-alternatives to set it as your default Java

update-java-alternatives -l
update-java-alternatives -s <jname>

edited Mar 12 '14 at 05:35

answered Mar 12 '14 at 05:20

Lee Duhem

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I really don't understand what is wrong here. This is the output `Reading package lists... Done` `Building dependency tree` `Reading state information... Done` `openjdk-7-jdk is already the newest version.` `0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.` `root@ubuserver3:/home/ubuadmin/JavaJars/HelloWordGPU# java -version` `java version "1.6.0_30"` `OpenJDK Runtime Environment (IcedTea6 1.13.1) (6b30-1.13.1-`1ubuntu2~0.12.04.1)` `OpenJDK Client VM (build 23.25-b01, mixed mode, sharing)` `root@ubuserver3:/home/ubuadmin/JavaJars/HelloWordGPU#` – PeakGen Mar 12 '14 at 05:22
@GloryOfSuccess It looks like you already installed `openjdk-7-jdk`. You could use `update-java-alternatives` to set it as your default java, please refer to the answer given by Elliott Frisch. – Lee Duhem Mar 12 '14 at 05:28
what does it ask for the next parameter? I am not a Linux person even I am doing this. – PeakGen Mar 12 '14 at 05:31
@GloryOfSuccess First part of the `-l` output. – Lee Duhem Mar 12 '14 at 05:36

Unable to install Java 6 and install 7

2 Answers2