[Solved]-have IntelliJ IDEA refresh the project and detect changed files-eclipse

Click File>Synchronize (or) shortcut ctrl+Alt+Y

There is a synchronise button in the tool bar. Click it and it will refresh the project explorer

I know this question was posted a few years ago, but maybe this info will help someone in the future. I was actually looking into a similar issue, and doing the following worked for me:

Go to Settings > Build, Execution, Deployment > Compiler and make sure "Make project automatically" is checked.

Right click on your Project in the left pane and click on "Synchronize"

You can see the status in the round circling icon at the bottom left of the IDE

Intellij can highlight variable instances, you just need to enable it . Further, if you invoke compile project, Intellij will just compile changed files (and hotswap when possible, if you are in debug mode & deploying to e.g. tomcat)