Why "Source > Organize Imports" does not work in Eclipse?

I am writning a Hello World SWT application in Eclipse (I follow instructions given by Eclipse). At some point I have to "Right click in the Java editor and select Source > Organize Imports".

I did it in Eclipse installed on Ubuntu.开发者_运维技巧 This operation has generated import statements in the beginning of my code. But it was not sufficient to make my program to work. I needed to add some import statements by hands and after that my code worked fine.

Now I am trying to do the same in Eclipse installed on Windows. In this case the situation is even worser. "Source > Organize Imports" does not change anything (it does not add any import statements to the beginning of the code).

Does anybody has any ideas why it does not work properly?

Scenario 1: The package that is to be identified by Eclipse may not be in your project classpath.

Scenario 2: Eclipse is not able to resolve your class name as there might be two different classes with same name in different packages. In such scenarios, it will pop-up a dialog asking you to select the appropriate class. Older version of eclipse may not pop-up leaving you to manually find and resolve.

Your source must be error free compile wise before any of these will be applied.