Wrapper Class in Java vs C#

Question

In case of Java when we write something like

Integer i = new Integer(20);

In the above case the obj is allocated on the heap

and in case of C#

Int32 i = new Int32();
i=10;

In this case the object is allocated on the stack

Are these just the difference in implementation wise or there are more differences too?

Correction: changed Integer to Int32 for C#

How you define `Integer` for C#? (there is `System.Int32`/`int`, but no `Integer`)... — Alexei Levenkov, Jul 03 '12 at 04:36
C# doesn't have explicit types representing boxed primitives. It's just an object that could be cast back to the appropriate type. It's nowhere near as complicated as it is in Java. — Jeff Mercado, Jul 03 '12 at 04:38

Habib · Accepted Answer · 2012-07-03T04:49:19.030

3

There is no Integer in C#, its either int or int32 and both are same. With respect to C# saying "Value types go to stack" is some what not correct. You need to see this article from Eric Lippert: The Truth About Value Types

Edit: based on comment:

Int32 and int are same, the two are synonymous.

edited Jul 03 '12 at 04:49

answered Jul 03 '12 at 04:36

Habib

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@Akash, Int32 and int are same, the two are synonymous. – Habib Jul 03 '12 at 04:49
@Akash: `int` _is_ `System.Int32`, it's merely an alias. – Jeff Mercado Jul 03 '12 at 04:49
@Akash, you may also check this thread http://stackoverflow.com/questions/62503/c-int-or-int32-should-i-care – Habib Jul 03 '12 at 04:52

score 3 · Answer 2 · answered Jul 03 '12 at 04:50

Many of the reasons you may wish to wrap a primitive in Java don't apply to C# because C# has structs instead of primitives. The following are some of the things structs can be used for that can't be done with prmitives:

They have methods. Eg http://msdn.microsoft.com/en-us/library/system.int32.aspx shows the methods available for int32. E.g converting to string is a method call.
They can be used in Generic data structures. E.G List < int > is perfectly fine.

When they are needed on the heap they can be boxed. This link explains it http://msdn.microsoft.com/en-us/library/yz2be5wk.aspx.

Wrapper Class in Java vs C#

2 Answers2