vaadin-framework/documentation/installing/installing-java.adoc

---
title: Installing Java
order: 30
layout: page
---

[[installing.java]]
= Installing Java SDK

A Java SDK is required by Vaadin and also by any of the Java IDEs.
Vaadin Framework 8 requires Java 8.
Java EE 7 is required for proper server push support with WebSockets.

[[installing.java.windows]]
== Windows

Follow the following steps:

. Download Oracle Java SE 8.0 from
link:http://www.oracle.com/technetwork/java/javase/downloads/index.html[http://www.oracle.com/technetwork/java/javase/downloads/index.html]

. Install the Java SDK by running the installer.
The default options are fine.

[[installing.linux]]
== Linux / UNIX

Most Linux systems either have JDK preinstalled or allow installing it through a
package management system. Notice however that they have OpenJDK as the default
Java implementation. While it is known to have worked with Vaadin Framework and possibly
also with the development toolchain, we do not especially support it.

Depending on your OS distribution, you may have to download Java JDK 8:

. Download Oracle Java SE 8.0 from
link:http://www.oracle.com/technetwork/java/javase/downloads/index.html[http://www.oracle.com/technetwork/java/javase/downloads/]

. Decompress it under a suitable base directory, such as [filename]#/opt#. For
example, for Java SDK, enter (either as root or with [command]#sudo# in Linux):

+
[subs="normal"]
----
[prompt]#+++#+++# [command]#cd# [replaceable]#/opt#
[prompt]#+++#+++# [command]#sh# [replaceable]##<path>##/jdk-[replaceable]##<version>##.bin
----
+
and follow the instructions in the installer.

. Set up the [literal]#++JAVA_HOME++# environment variable to point to the Java
installation directory. Also, include the [literal]#++$JAVA_HOME/bin++# in the
[literal]#++PATH++#. How you do that varies by the UNIX variant. For example, in
Linux and using the Bash shell, you would add lines such as the following to the
[filename]#.bashrc# or [filename]#.profile# script in your home directory:

+
----
export JAVA_HOME=/opt/jdk1.8.0_31
export PATH=$PATH:$HOME/bin:$JAVA_HOME/bin
----
+
You could also make the setting system-wide in a file such as
[filename]#/etc/bash.bashrc#, [filename]#/etc/profile#, or an equivalent file.
If you install Apache Ant or Maven, you may also want to set up those in the
path.

+
Settings done in a [filename]#bashrc# file require that you open a new shell
window. Settings done in a [filename]#profile# file require that you log in into
the system. You can, of course, also give the commands in the current shell.