WebDriver playback in Selenium IDE requires the Standalone Selenium Server. The Standalone Selenium Server in turn requires a few supporting pieces of software. I have decided to break the whole process into individual parts to make it easier on the eyes. So onwards to the first step of installing Java.
This post deals with installing Java. If you are one of the lucky ones, Java is already installed for you and you can skip this whole part.
Check if Java is already installed
You can check if Java is already installed and configured for you by running it with the -version option. So open a command window on Windows or a terminal window on Linux and MacOS and fire the following command.
If Java is installed and configured, you will see a response like the following.
java version "1.6.0_23" Java(TM) SE Runtime Environment (build 1.6.0_23-b05) Java HotSpot(TM) 64-Bit Server VM (build 19.0-b09, mixed mode)
If you do not see something like above, Java may be installed, but may not be on the path. You will need to figure out where it is and how to get it on your path or you can simply install the latest version. Searching in the file system for java or looking at the installed software may help.
Any version from 1.6 onwards should be sufficient for the Standalone Selenium Server. If your version is lower than 1.6 you should install a new version.
Choose the right Java bundle from JRE or JDK
Java comes in two different bundles for download, viz., the JRE or the JDK. The JRE or the Java Runtime Environment provides all the necessary software to run Java applications. The JDK or Java Development Kit includes the JRE and also provides tools to create and build your own Java applications. For running the Standalone Selenium Server, a JRE is sufficient. If you plan to do or try some Java development, get the JDK instead.
Choose the right Java version
The latest version as of writing is Java 7, which is a short form for Java version 1.7.x_xx. An older version (Java 6 / 1.6.x_xx) is also available. I would recommend getting the latest update of Java 7 unless some reason prohibits you from installing the latest version. As I mentioned before any version from 1.6 onwards should be sufficient for the Standalone Selenium Server.
Other Java variations
The amount of download options on the Oracle downloads page can be daunting. Along with the JRE/JDK choice and the Java version there is also the option of 32-bit and 64-bit versions. This usually depends on the type of your Operating System. If you have a 32-bit OS, choose the 32-bit Java version. If you have a 64-bit OS, choose the 64-bit Java version. If you do not know what I am talking about or do not know how to find out, simply go with the 32-bit Java version.
Along with this you will have to choose from Java SE, Java EE, Java ME and a bunch of other variations. We require Java SE or Standard Edition. You can safely ignore the rest. You can also ignore the rest of the cobundles which contain additional software like NetBeans as well as all downloads in the additional resources.
Download and Install Java from the Oracle website
Go to the Java download page and download the Java version of your choice. Hopefully the previous sections have given you enough details to choose one. For windows users, the 32-bit version is called ‘Windows x86‘ and the 64-bit version as ‘Windows x64‘. I would recommend getting the offline + exe version from the downloads list. The installation instructions for Windows, MacOS and Linux as available in the Installation Guide. Hopefully you will have Java installed and configured when all this is done. You can verify using the java -version as mentioned earlier. You may need to open a new command window or terminal window for a newly installed Java to be accessible. If this fails, getting your friendly neighbouring Java Developer to help out may work. Beer is usually known to provide sufficient motivation, thought you might want to wait until they finish installing Java or risk getting this :-). (Anyone planning to get Simon drunk enough to do the next one :-))
You should now be ready to go to the next step which is getting the Standalone Selenium Server.