There is 'An empty string is represented as "". It is a character array of zero characters. A null string is represented by null. It can be described as the absence of a string instance.' as the second paragraph after "Validating Null and Empty Strings" on the page named "Using Bean Validation" at http://docs.oracle.com/javaee/6/tutorial/doc/gircz.html. The second sentence is not correct in the Java context. A character array is mutable. A String is not. So a string in Java is not a character array. It may be more technically accurate to say "It is a character sequence of zero characters." As String implements CharSequence, this is technically correct as well as conceptually correct.