Difference between null and empty (“”) Java String

Question

What is the difference between null and the \"\" (empty string)?

I have written some simple code:

String a = \"\";
String b         


        

Answer 1

What your statements are telling you is just that "" isn't the same as null - which is true. "" is an empty string; null means that no value has been assigned.

It might be more enlightening to try:

System.out.println(a.length()); // 0
System.out.println(b.length()); // error; b is not an object

"" is still a string, meaning you can call its methods and get meaningful information. null is an empty variable - there's literally nothing there.