As far as I know , you can never do it (I searched for it, no luck). Even if there are softwares which can be used for Swift and Objective-C, they could be illegal.
You can either try coding Swift or Objective-C on the web, or you can:
Step 1. Install a Virtualbox software for windows
Step 2. Download OSX .iso file
Step 3. Run that on your virtualbox
Step 4. If your OSX works fine, download XCode from its App Store.