Re-scanning entire project for syntax errors, missing imports, etc?

I noticed that if I make a change that causes errors in files that I don't have open at the moment (changing a method signature, moving classes between packages, etc), the files don't show up with the red squiggly line in the project tree, indicating the error. I have to hit compile and wait for the compiler to stop at an error to find, say, a missing import or two, which is frustrating and time consuming.

Is there a way to "open" an entire project at once so that I can see the errors present in the code?

(I understand that this technically shouldn't be a problem because of IDEA's refactoring tools, but I have run into problems even though I felt I was using them correctly, and sometimes I do large scale changes with regex as well.)