You've got 20 editors open , and scrolling through all those editor tabs to navigate between them is taking a long time.
Use the workbench editor's navigation history, which works much like a web browser's history. Just click the back arrow in the workbench toolbar as you would in a web browser to go back to the previous editor. (Or use Navigate menu items such as Navigate Backward, or keyboard shortcuts such as Alt-Left Arrow.)
When you work with Eclipse on extended projects, you'll find the editor area filling up with editors. And as the editors get more cramped, Eclipse makes their tabs smaller and the text in them more abbreviated. The more editors you have open, the more difficult it becomes to move between them. One way to ameliorate this problem is to bear in mind that you can use navigation controls to move between recently used editors.