

The changes above will be applied for the new files, but if you want to change spaces to tabs in an existing file, then you should format the file by pressing Ctrl + Alt + L. or from Other Settings > Default Settings., because the change from one window will be available in the other window. It seems that it doesn't matter if you check/uncheck the box from Settings. The Nexus IQ plugin for IntelliJ IDEA scans your open source dependencies for policy violations and security vulnerabilities, and provides actionable insights and remediation advice to help you fix issues in just a few clicks without leaving your favorite tools. > Editor > Code Style > Detect and use existing file indents for editing Select the best open source components for your projects using precise security intelligence directly within IntelliJ. File > Other Settings > Default Settings.> Editor > Code Style > Detect and use existing file indents for editing > Editor > Code Style > Java > Tabs and Indents > Use tab character

The paths in the other answers were changed a little:

To convert tabs to spaces, you can chose "To Spaces" from the same place. If you want to convert tabs to spaces, you can write "spaces", then choose "To Spaces". IntelliJ IDEA 15 Only for the current fileĬtrl + Shift + A > write "tabs" > double click on "To Tabs"
