If you go to Github projects, they provide you a link to download the sourcecode as a zip file (if you do not want to configure any git client). But in google code projects, you are not given this option is some of the projects and rather you are presented with SVN URL to checkout. In this tutorial, I am giving an example of checking out sourcecode from cod.google.com to your local machine using Tortoise SVN client.
1) Download an install any SVN client (e.g. Tortoise)
Go to http://tortoisesvn.net/downloads.html and install the latest version of it in your development machine.
2) Create a blank folder in file system and checkout sourcecode
Now create an empty folder in your workspace area. And right click on it. Click on “SVN Checkout…” option.
Now copy the SVN checkout URL from google code project till trunk path only.
Copy the path in checkout dialog in your workspace and click OK.
Now all the files will be downloaded from google code project to your local workspace. Import the code in suitable editor and start working on it.
Happy Learning !!