If you don't have a Linux system to use for your leJOS EV3 projects, you can still run one on top of your Windows or Mac system using VirtualBox:
To get started first you need to download VirtualBox for your computer:
be sure to download and install both the main system and the extension pack. If during the install you are asked make sure you choose to install USB support and networking.
Once VirtualBox is up and running we need to install Ubuntu, it is possible to install from standard install media but I choose to use a pre built image from the VirtualBoxes project:
The image I used is this one:
Once downloaded expand the file to a location of your choice. This file will form the basis of the VirtualBox virtual system image. I expanded the file into a directory called vms in my home directory. The above file will expand to a file called ubuntu-12.10-desktop-i386.vdi. Now we need to create the new virtual machine. From the VirtualBox Manager choose New, then follow the steps below:
1. Give your VM a name I called mine "Ubuntu for EV3".
2. Check that the type and version are Linux and Ubuntu, then click next.
3. Change the amount of memory allocated to the VM to be 1024MB. then click next.
4. Choose the option to use an existing virtual hard drive, then locate the disk image you extracted above. Select the image and choose next.
At this point you have created the basic VM. However before we go ahead and boot it, it is worth making a few other changes. In the display settings, increase the amount of video memory (I use 128MB) and also enable 3D acceleration. In the USB settings you should enable USB 2.0 and create a filter to allow access from the VM to your SD card reader (you will need this access to create the leJOS bootable SD card).
Once you have made the above changes go ahead and start the VM. You will need to configure your Linux system, add users etc. You should also be sure to install the VirtualBox guest editions as this makes things much easier to use.