args.length() is showing compilation error where as args.length is working fine in command line argument

Question

If I do args.length(); it is showing compilation error where as args.length is working fine.

but if it is not command line argument for eg. String str = "hello"; in this str.length is not working but str.length() is working fine.

please help!

Answer 1

Assuming you refer to the args parameter of a main method, that's because arrays do not provide a length() method like String s, but a length public property, returning int .

See docs here .

Answer 2

String as an object has a built in method called length()

Array as an object does not have a built in method length() , but it has a property called length

Answer 3

The parameter arg of the main method is an Array .

Arrays have a public property length unlike Collections or Strings that have length() method

Answer 4

The public final field length , which contains the number of components of the array. length may be positive or zero.

There is no length() method. Documentation .

String class has a method called length() ( Docs )