IIMBU - Imported Items Must Be Used

It is not legal to import a class or an interface and never use it. This rule checks classes and interfaces that are explicitly imported with their names - that is not with import of a complete package, using an asterisk. If unused class and interface imports are omitted, the amount of meaningless source code is reduced - thus the amount of code to be understood by a reader is minimized.

Wrong

import java.awt.*;
import java.util.Dictionary;
import java.util.Hashtable;
import java.util.Stack;
import java.util.Vector;
class IIMBU {
    Dictionary dict;
    void func (Vector vec) {
        Hashtable ht;
        // do something
    }
}

Tip: Delete unnecessary imports.