String

[selvi]

what is the difference between null value and empty string?

[jeyasree]

Very big!

Empty String is an OBJECT of type: String (new String()

)
It means there is an object associated to variable and you can call object methods:
String s = new String(); //object initialization (empty string)
System out println( s.length() );


NULL String means that there is no reference to any OBJECT.
String s;
System.out.println( s.length() ); //this will throw NullPointerException

[servlet]

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