using package name to create objects in Java

Question

I was looking at someone's else code and they code it using package names.

String filename = "";

java.io.PrintWriter writer;

writer = new java.io.PrintWriter(new java.io.FileWriter(filename));

Is the syntax the equivalent had it not been coded with package name? Is there any use coding it with package names since Java allows it?

Answer 1

You have to use the package names (or "fully-qualified names" - this refers to the package name and the class name together) if:

1. You need to use two classes of the same name in the same source file.
2. You didn't import the classes you're using for whichever reason. (Usually insanity.)
3. You imported the classes but are still using the package names anyway because I don't know.