If a file is read-only, it is marked with the closed lock icon
in the
Status bar, in its editor tab, or in the Project tool window.
If a file is writable, then it is marked with the open lock icon 
in the Status bar.
This section describes how to change read-only attribute of a file.
If a read-only status is set by a version control system, it's suggested that you use IntelliJ IDEA version control integration features. For more information, see Version Control with IntelliJ IDEA.
- Open file in the editor, or select it in the Project tool window.
- Do one of the following:
- On the main menu, choose , or .
- Click the lock icon in the Status bar.