Arrays - basic question

[ankur rathi]

when we create any array object .
int[] i = new int[3];
the hierarchi is :

 
Object[]
   ^
   |
 
Arrays[]
   ^
   |
int[]
 

is this correct .
thanks .
[ January 31, 2005: Message edited by: rathi ji ]

[shandilya popuru]

hi

i think int[]`s direct super class is lang.Object

this code

int[] s=new int[10];
System.out.println(s.getClass().getSuperclass().toString());

gives java.lang.Object as o/p

[Edwin Dalorzo]

Hierachy depends if your array is a primitive data type array or a reference type array.

Primitive data types arrays are direct descendants of Object class, but not of Object[].

However reference type arrays are direct descendants of Object[].

So hierachy would be like this for primitive data types


Object
^
byte[] short[] char[] int[] long[] float[] double[] boolean[]

But for reference types:

Object
^
Object[]
^
Integer[] MyClass[] Float[] String[]

Hope it helps!

[ankur rathi]

thanks Edwin , but what about Arrays class . when it is useful .
thanks a lot .

[ankur rathi]

Can any body tell me , what is the use of Arrays class .

thanks .

[Sumit Deshpande]

http://java.sun.com/j2se/1.4.2/docs/api/index.html

"This class contains various methods for manipulating arrays (such as sorting and searching)."

[Nicholas Cheung]

what is the use of Arrays class .

If you are refering to java.util.Arrays, its main usage is to provide utilities (static methods) to manipulate arrays. All of its methods are static (just like java.lang.Math).

Nick

[ankur rathi]

Thanks Nick ,
I got the point . Actually I was thinking that every array is implicitly sub class of Arrays class . But this is not the case , primitives array extends from Object class ( as every other class extends ) & reference variable array extends from Object[] class & that extends Object class . And Arrays class provides static methods for manuprlatings this arrays .

Thanks once again to all .