How to Install Oracle Java on Ubuntu Linux? Java Performance Problems

Main reason of this problem is the installation of OpenJRE/JDK instead of OracleJRE/JDK

• Start by learning your java version by typing

java -version

• If you have OpenJDK installed on your system, you got something like this

java version "1.6.0_21" OpenJDK Runtime Environment (IcedTea6 1.10pre) (6b21~pre1-0lucid1) OpenJDK 64-Bit Server VM (build 19.0-b09, mixed mode)

• Remove JDK and JRE by typing

sudo apt-get autoremove openjdk-6-jre
sudo apt-get autoremove openjdk-6-jdk

• Create a folder for new Java installation

sudo mkdir -p /usr/local/java

• Download Oracle JRE and/or JDK from http://www.oracle.com/ as TAR.GZ file

• Copy downloaded files into Java installation folder

sudo cp jdk-7-linux-x64.tar.gz /usr/local/java cd /usr/local/java

• Open compressed files into this directory

sudo chmod a+x jdk-7-linux-x64.tar.gz tar xvzf jdk-7-linux-x64.tar.gz

• Edit /etc/profile to change system path

sudo gedit /etc/profile

• Go to the end of the file and add similar lines for your java version, then save and exit.

JAVA_HOME=/usr/local/java/jdk1.7.0 PATH=$PATH:$HOME/bin:$JAVA_HOME/bin JAVA_HOME=/usr/local/java/jre1.7.0 PATH=$PATH:$HOME/bin:$JAVA_HOME/bin export JAVA_HOME export PATH

• Inform Ubuntu system about JDK/JRE location

sudo update-alternatives --install "/usr/bin/java" "java" "/usr/local/java/jre1.7.0/bin/java" 1 sudo update-alternatives --install "/usr/bin/javac" "javac" "/usr/local/java/jdk1.7.0/bin/javac" 1

• Inform Ubuntu system about default JDK/JRE

sudo update-alternatives --set java /usr/local/java/jre1.7.0/bin/java
sudo update-alternatives --set javac /usr/local/java/jdk1.7.0/bin/javac

• Reload your profile information

. /etc/profile

• Check your Java version again

javac -version

added 11 years ago