To develop and run Java applications, you will need two things: the Java Runtime Engine (JRE) and the Java Development Kit (JDK). These can be easily downloaded from Oracle (formerly Sun) and installed on your Windows machine.
It is easy to install Java on Windows these days. You just need to download Java JDK and JRE package and install it. There is no need to make two downloads since now you can download everything as one package.
1. Download Java JDK and JRE
Go to http://www.oracle.com/technetwork/java/javase/downloads/index.html and download java JDK 7. Just click the big box where it says “Java Platform (JDK) 7″
Accept the licence agreement. Select the Windows version that you want to download:
Windows x86 (32 bit)
Windows x64 (64 bit)
If you don’t know if your PC is 32 bit or 64 bit, then here is how to find out.
2. Install the Java JDK and JRE
When it is finished downloading, run the executable file. Leave all the defaults during the installation process.
Now you can see that java has been installed inside this folder:
You should see two folders from one installation: jdk and jre.
Now you are ready to download and install Eclipse and tell it which java version to use.