what is the difference between "" and " "?

Hi, what is the difference between "" and " "?
regards,
Guoqiao

i guess, "" is equivalent to null whereas " " represents a white-space character.
correct me if i am wrong.
/Aakanksha

No. "" does not equal null. "" represents an empty String but not a null.
Try comparing these two Strings:
s1 = "";
s2 = null;
System.out.println(s2.equals(s1));
System.out.println(s1.equals(s2));
The first test will answer false. The second test will throw a null pointer exception.

"" is an empty String, whereas " " is a non-empty blankspace character String
-- Sandeep