Installing Oracle JDK 7 (Java Development Kit) on Ubuntu

There are many posts on this topic if you search on Google. This post just explains the steps I use to install JDK 7 on my laptop.

Download the JDK from Oracle. The latest version as of now is Java SE 7u51.

I'm on 64-bit machine, therefore I downloaded jdk-7u51-linux-x64.tar.gz

It's easy to get the tar.gz package as we just have to extract the JDK.

I usually extract the JDK to /usr/lib/jvm directory.


sudo mkdir -p /usr/lib/jvm
cd /usr/lib/jvm/
sudo tar -xf ~/Software/jdk-7u51-linux-x64.tar.gz
sudo update-alternatives --install "/usr/bin/javac" "javac" "/usr/lib/jvm/jdk1.7.0_51/bin/javac" 1
sudo update-alternatives --install "/usr/bin/java" "java" "/usr/lib/jvm/jdk1.7.0_51/bin/java" 1
sudo update-alternatives --install "/usr/lib/mozilla/plugins/libjavaplugin.so" "mozilla-javaplugin.so" "/usr/lib/jvm/jdk1.7.0_51/jre/lib/amd64/libnpjp2.so" 1
sudo update-alternatives --install "/usr/bin/javaws" "javaws" "/usr/lib/jvm/jdk1.7.0_51/bin/javaws" 1

After installing, we should configure each alternative

sudo update-alternatives --config javac
sudo update-alternatives --config java
sudo update-alternatives --config mozilla-javaplugin.so
sudo update-alternatives --config javaws

Now we can configure JAVA_HOME. We can edit ~/.bashrc and add following. 
export JAVA_HOME=/usr/lib/jvm/jdk1.7.0_51/

That's it! :)

UPDATE:

Please check Oracle Java Installation script for Ubuntu. All above steps are now automated via an installation script: https://github.com/chrishantha/install-java

Comments

Post a Comment

Popular posts from this blog

Specifying a custom Event Settings file for Java Flight Recorder

Image
When you are using Java Flight Recorder (JFR), the JFR will use an event settings file to check which event types to record. By default in JFR, there are two settings, "default" and "profile". The default setting is recommended for Continuous Recordings as it has very low overhead (typically less than 1% overhead). The profile setting has more events and useful when profiling the application. As mentioned in my previous blog post regarding  Java Flight Recorder Continuous Recordings , we use following arguments to do a Continuous Recording. -XX:+UnlockCommercialFeatures -XX:+FlightRecorder -XX:FlightRecorderOptions=defaultrecording=true,disk=true,repository=./tmp,dumponexit=true,dumponexitpath=./ Note: According to the Oracle documentation on " java " command, we should be able to specify "settings" parameter to the -XX:FlightRecorderOptions. However, the settings parameter has no effect when used with the -XX:FlightRecorderOptions and
Read more

Flame Graphs with Java Flight Recordings

Flame Graphs Brendon D. Gregg , who is a computer performance analyst , has created  Flame Graphs to visualize stack traces in an interactive way. You must watch his talk at USENIX/LISA13 , titled Blazing Performance with Flame Graphs , which explains Flame Graphs in detail. There can be different types of flame graphs and I'm focusing on  CPU Flame Graphs  with Java in this blog post. Please look at the Flame Graphs Description  to understand the Flame Graph visualization. CPU Flame Graphs and Java Stack Traces As  Brendon  mentioned in his talk, understanding why CPUs are busy is very important when analyzing performance.  CPU Flame Graphs  is a good way to identify hot methods from sampled stack traces. In order to generate CPU Flame Graphs for Java Stack Traces , we need a way to get sample stack traces. Brendon has given examples to use jstack  and Google's lightweight-java-profiler . Please refer to his perl program on generating  CPU Flame G
Read more

Java CPU Flame Graphs

Update (September 14, 2015): Java 8 Update 60 was released on August 18, 2015. There are some recent changes to "perf-map-agent". There is no longer a script named "perf-java" and you should use "bin/create-java-perf-map.sh " Brendan Gregg shared an exciting news in his Monitorama talk: The " JDK-8068945 " is fixed in Java 8 Update 60 Build 19 ! Without this fix, it was not possible to see full stack in Java with Linux perf_events and standard JDK (without any patches). For more information, see Brendan's Java CPU Flame Graphs page. The Problem with Java and Perf First of all, let's see what's the problem with using current latest Java and perf. For this example, I used the same program explained in my previous blog post regarding FlameGraphs . java org.wso2.example.JavaThreadCPUUsage.App Then I sampled on-CPU functions for Java program using perf. (See Brendan's Perf Examples ) sudo perf record -F 99 -g -
Read more