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Returning Arrays !

vamsi acharya
Ranch Hand

Joined: Jun 28, 2009
Posts: 55

Hello guys , is returning an array to an Object type Method legal ?? If so how ?? ..Consider the following code

My certification book says its legal , i can't understand how !!


"Known is a drop , unknown is an ocean " !
Stephan van Hulst
Bartender

Joined: Sep 20, 2010
Posts: 3647
    
  17

An array is a subtype of Object.

Every type in Java, except for the primitives (boolean, int, float, char, etc.) are subtypes of Object.
Plamen Kamenov
Greenhorn

Joined: Aug 31, 2010
Posts: 1
Hi, it is legal, because the all arrays are objects like everything else in Java.
Only when you have to assign the returning result, you need to cast to int[], for example.
vamsi acharya
Ranch Hand

Joined: Jun 28, 2009
Posts: 55

Stephan van Hulst wrote:An array is a subtype of Object.

Every type in Java, except for the primitives (boolean, int, float, char, etc.) are subtypes of Object.


I know 'String' is a class hence is a subclass of 'Object' , I also know 'Arrays ' is class so its a subclass of Object but when we declare an array with '[]' how is it possible that it could be a subclass of the Object ???
Stephan van Hulst
Bartender

Joined: Sep 20, 2010
Posts: 3647
    
  17

Because that's what the language designers decided. All arrays are subtypes of Object.

Try the following line: System.out.println(nums instanceof Object);
vamsi acharya
Ranch Hand

Joined: Jun 28, 2009
Posts: 55

Stephan van Hulst wrote:Because that's what the language designers decided. All arrays are subtypes of Object.



Where do the arrays reside in the API ???
Matthew Brown
Bartender

Joined: Apr 06, 2010
Posts: 4422
    
    8

vamsi acharya wrote:Where do the arrays reside in the API ???

You need to check the Java Language Specification rather the the API. From that link:
The direct superclass of an array type is Object. Every array type implements the interfaces Cloneable and java.io.Serializable.
Stoian Azarov
Ranch Hand

Joined: Jun 01, 2011
Posts: 113
to make things more fun, here are some more legal statements that might look ridiculous:

on the contrary this is already illegal:

Regards


vamsi acharya
Ranch Hand

Joined: Jun 28, 2009
Posts: 55

Thank you very much people !!
 
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subject: Returning Arrays !