Java is a programming language originally developed by Sun Microsystems. Questions here should be about the installation, configuration and troubleshooting a JVM (Java Virtual Machine) or a JRE (Java Runtime Environment). Programming questions (unless directly related to Ubuntu) should be asked ...

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68
votes
9answers
87k views

How do I install Java?

How do I install Java and also the plugin in my browser so websites with Java work?
196
votes
21answers
316k views

How can I install Sun/Oracle's proprietary Java JDK 6/7/8 or JRE?

I want to install Oracle's JRE and to update to the latest version with the Software Updater when they released. Is there a Ubuntu package that is provided by Canonical or Oracle? Before release Java ...
252
votes
0answers
337k views

How do I install Oracle Java JDK 7? [duplicate]

If I downloaded the latest JDK from Oracle, do I just download the .tar file and extract it to /usr/lib/jvm/?
75
votes
11answers
164k views

How do I install Oracle JDK 6? [duplicate]

Most of the software is not thoroughly tested with Java 7 and I would like to install Oracle's JDK 6.0 on Ubuntu 11.10. Could someone please provide me the instructions for the same?
28
votes
11answers
86k views

How can I install Minecraft?

I have tried many tutorials but none of them are clear enough. I have also tried installing it using Wine but it won't update and Wine goes gray and stops working. Does anybody know an easy way to ...
33
votes
9answers
96k views

How to completely uninstall Java?

How can I completely remove all traces of Java on my system? I already know how to install it in case I need it again.
17
votes
6answers
20k views

Unsatisfied Link Error and missing .so files when starting Eclipse

I upgraded to the 12.04 beta yesterday. Now, when I try to start Eclipse, I get the splash screen and then this error message: An error has occurred. See the log file ...
28
votes
6answers
8k views

How can I remove duplicate icons for “launched” java programs in the launcher?

When launching java programs (like IntelliJ IDEA and Crashplan) in Natty's Unity launcher, duplicate icons are shown (see image). For IntelliJ I created the .desktop file, for Crashplan the .desktop ...
28
votes
2answers
17k views

“sha256sum mismatch jdk-7u3-linux-x64.tar.gz ” error when trying to install Oracle Java

i recently tried installed java 7 on ubuntu 12.04 and i think i screwed something up I followed the instructions given here. First you need to remove openjdk for this run the following command from ...
13
votes
5answers
10k views

Will Sun's Java be available from Canonical's partner repository?

I just discovered that Oracle's (Sun's) Java6 has vanished from the Canonical's partner repo. Before java was taken from all repositories I had purchased Minecraft for play in Ubuntu. After recent ...
28
votes
7answers
79k views

Installing Chrome Java Plugin

I've been trying to install the Java plugin for Chrome for a couple hours now, and I figured it was time to ask people with more experience. I can't seem to get it working. My current Java version is ...
6
votes
2answers
2k views

is OpenJDK Vulnerable to 0-Day Exploit?

I was curious to know if OpenJDK is also vulnerable to the Zero-Day Exploit that is currently afflicting Java 7 because of which experts are telling people to disable Java until a solution is found on ...
33
votes
1answer
51k views

How do I update Oracle Java 7 (JDK and JRE)

Recently, I've installed JDK 7 from the Oracle site, using these instructions. Now, I'm wondering what is the correct method to update it (or, better, to keep up-to-date automatically)? For instance, ...
13
votes
9answers
26k views

Minecraft in jdk 1.7.0_u2 x64

I have Ubuntu 11.10 64-bit and I installed JDK 1.7.0 update 2 x64 via webupd8 page. But currently I have problem with minecraft game. After downloading launcher from Minecraft.net and lauch the game ...
8
votes
2answers
9k views

“No such file or directory” when invoking java

I'm trying to re-install Oracle JDK 7 32 bit to 64 bit Ubuntu (previously 64 bit JDK was installed). JDK is currently present at /usr/lib/jvm/jdk1.7.0. I invoke sudo update-alternatives --remove ...
10
votes
5answers
19k views

How do I make java default to a manually installed JRE/JDK?

I have Ubuntu 12.04 amd64 installed on my machine, on the previous versions of Ubuntu it was deadly easy, now there is this command update-java-alternatives with a really bad man page. I just have my ...
7
votes
1answer
6k views

How do I reenable opening jar files by double clicking on them?

How can I make "double click to run" the default behaviour of a jar-file on Nautilus? There is no "Open with OpenJDK Java 7 Runtime" on the "Open with" tab under Properties.
6
votes
0answers
10k views

How to install Oracle Java web plugin on Chrome in 12.04? [duplicate]

Possible Duplicate: How can I install Sun/Oracle’s proprietary Java 6/7 JRE or JDK? I've tried a whole lot of guides, but at best I ended up with neither Google Chrome not Firefox ...
1
vote
1answer
590 views

Oracle java7 config

I've installed Oracle Java 7 according to this guide. When I run sudo update-java-alternatives -s java-7-oracle, it gives me : update-alternatives: error: no alternatives for ...
0
votes
2answers
348 views

Best Practice for Installing Java on Ubuntu / is it secure?

Much has been said about the security risks associated with Java. However the burp suite (pen test) depends on Java. Is it secure to install Java? if so, how to properly do it? My Ubuntu is a web ...
5
votes
3answers
733 views

How to revert back to OpenJDK?

I had installed sun-java, but I want to revert back to OpenJDK 7. I was trying to re-install from the terminal using the command sudo apt-get install openjdk-7-jre, same from Synaptic and Software ...
1
vote
1answer
1k views

JDK x64 fails to unpack in Ubuntu 13.04

New to ubuntu, I have just installed the OS in my VMPlayer. I am trying to install Oracle (Sun) Java 6 onto my Ubuntu 13. As per the instruction given here I download jdk-6u45-linux-x64.bin from the ...
1
vote
1answer
984 views

IcedTea plugin not working in Midori web browser

I have Lubuntu 13.04, and I use the Midori WebBrowser. I initially had a problem with the plugins, but later on, I could activate Flash and Java. I use the IcedTea browser plugin to view Java content. ...
11
votes
2answers
10k views

Changing JVM in Java

I only recently discovered the different JVM's on the wiki page and thought I'd start tinkering. Its been difficult to find documentation on how to configure Java on Ubuntu though. Lets say I wanted ...
23
votes
4answers
40k views

How to replace OpenJDK 6 with OpenJDK 7?

Surprisingly (as OpenJDK 7 was released to general availability about 4 months ago) Ubuntu 11.10 still uses OpenJDK 6 instead of 7 by default. How do I best fix this? I'd prefer to remove OpenJDK 6 ...
9
votes
8answers
26k views

Java JRE will not install due to “tar: Error is not recoverable” error

I have been trying to get Java for the past day now. I followed several tutorials but I keep getting the same error. After I put in tar -xvf jre-7u4-linux-i586.tar.gz it says Cannot open: No such file ...
5
votes
1answer
1k views

How to prevent openjdk-6-jre-headless from clobbering Oracle JDK installation?

My automated build server runs a job that depends on Apache Ant. The script invokes apt-get install ant. Ant depends on openjdk-6-jre-headless which runs update-alternatives making itself the default ...
3
votes
4answers
7k views

Running 32-bit Firefox with sun-jre in 64-bit Ubuntu [duplicate]

I am trying to run juniper networks connect program to vpn into work and it only works on 32bit sun jre. All the things I have found with google failed so far. I can't use any scripts, like ...
3
votes
1answer
12k views

Cannot Update Java plugin for Google Chrome

I keep getting the "Java plugin out of date" box whenever I open a page with embedded Java. I use the link provided, which has no auto-install. I've unzipped the tarball into /usr/lib/jvm/. I've used ...
3
votes
6answers
10k views

Cannot execute Java program: UnsupportedClassVersionError

I have installed JDK 6, but I can't execute a Java program. For example, I have made test.java. I compile it with javac tes.java and there's no error when I compile it, but when I want to execute ...
1
vote
2answers
6k views

Installing Matlab 2012a (32-bit) in Ubuntu 12.04 LTS java problem

This is my first posting here, so please be gentle. I am having a problem installing Matlab 2012a (32-bit) in Ubuntu 12.04 LTS. I have trawled around the web and have seen similar problems reported, ...
35
votes
10answers
90k views

How to correctly remove OpenJDK/OpenJRE and set SunJDK/SunJRE as Default

Ubuntu seems to favour OpenJDK/JRE very much over Sun JDK/JRE. Even after I installed Sun JRE, JDK and plugin and spent some time plucking out OpenJDK-related packages, apt-get has installed them back ...
11
votes
2answers
28k views

Installing Eclipse Kepler and Java JDK

I need some help to set up the Eclipse Kepler 4.3 and Java JDK last version on Xubuntu, I whould like to do it by the command terminal. Which are the right commands?
12
votes
2answers
8k views

How can I get a java apps to use the GTK+ theme?

Is there a way to get java apps to use my gtk theme?
16
votes
4answers
31k views

How to set JAVA_HOME for OpenJDK?

How can we set JAVA_HOME environment variable for OpenJDK?
5
votes
1answer
566 views

How do I submit .jar file to the ubuntu software center

I am writing an app using JAVA Swing for all platforms. After that I want to add this app to Ubuntu Software Center for free Is it possible? My app is just one *.jar file, its helping to play card ...
3
votes
2answers
4k views

How to update Eclipse 3.5.2 to 3.6.2?

I want to develop swing applications using the visual editor in Eclipse, but it need Eclipse 3.6. But it is already up-to-date using synaptic package manager. Is there a separate PPA for the version ...
8
votes
3answers
23k views

Can I install a 32-bit Java in addition to a 64-bit version?

For normal development I'm using the 64-bit VM which comes when I install the Java development kit (OpenJDK) with the package manager. But there are some Java applications (containing native ...
4
votes
3answers
1k views

How to shutdown/restart/suspend … without authentication or confirmation?

I am looking for a terminal command to shutdown without having to write down my password and without installing any extra programs. As when clicking the shutdown button, why it is not asking me for ...
1
vote
4answers
6k views

Eclipse does not want to use openjdk-7

I am on a new installation of Ubuntu. I install all the updates, and then restart. I then install openjdk-7-jdk from apt, then I restart. Then I install eclipse-platform, eclipse-jdt, and eclipse-cdt. ...
13
votes
4answers
51k views

How can I execute a .jar file from the terminal

I know that to execute a file, I use the . command, then the file name with a space between them. But I'm trying to execute a .jar file using the . and it does not work. I went into the properties and ...
10
votes
2answers
16k views

Minecraft jar not marked as executable

I looked up several tutorials on how to install and they dont work. I do everything correctly but then i get this: The file '/home/mike/Downloads/minecraft.jar' is not marked as executable. ...
4
votes
1answer
293 views

How to install Groovy?

I don't know how to install files to ubuntu. So kindly say me how to install groovy?
3
votes
2answers
7k views

How set CLASSPATH variable for a folder in Ubuntu

I know that export CLASSPATH=/usr/local/java/tools.jar:$CLASSPATH will add tools.jar to the CLASSPATH, but i want to set folder to the CLASSPATH like this export ...
3
votes
2answers
1k views

How do I install a 32-bit Java runtime on an amd64 server with multiarch?

I'm a long time Ubuntu user, but I haven't been following the community for the last several versions. I just did fresh default minimal amd64 install of Oneiric and I need a 32-bit JRE for a ...
2
votes
4answers
14k views

Netbeans 7.0.1 installed but won't run

I installed Netbeans 7.0.1, and I've made sure to install all the JDKs and JREs I could find. It installed without errors. I also saw this question and made sure I followed all the instructions there ...
2
votes
2answers
2k views

How to run a script at startup?

i want to start a java application at start up. I added the script file in init.d and the process got started . But the owner of the process is root. So when the java process is trying to write a ...
2
votes
1answer
1k views

How do I install Java 5?

I followed the approach for Ubuntu 9.10, to install java 5 but it is saying after executing the command update, E: Could not get lock /var/lib/apt/lists/lock - open (11: Resource temporarily ...
1
vote
4answers
986 views

Eclipse Error on Ubuntu 13.10

I have successfully installed Oracle Java 64 bit version on my machine (checked with java -version). Later I have downloaded Eclipse Kepler 64 bit but when I start it, it does not work and it is ...
0
votes
2answers
48 views

Where to write java programs on ubuntu?

I want on write java programs on ubuntu. I have java on my windows OS and I write programs in Notepad++ and compile and run it in command prompt. I installed java on ubuntu. What should I use to write ...