Changing JSON Editor in Eclipse to Visual Studio Code in Mac

The default JSON Editor in Eclipse is buggy and doesn't have many features to control how to structure your JSON document.

You should change the editor to use an external editor namely Visual Studio Code (Free)

Steps to use Visual Studio Code

• Install Visual Studio Code for Mac
• Right Click the .json file in Eclipse
• Select Other 
• Select Code (Visual Studio) pick and check "use this for all *.json" files at the bottom

Now if you double click the file, it would open in Visual Studio code.
This has better options like spacing, file management and can handle formatting for large JSON documents