Object[] and Object

[Anthony Karta]

why we canNot pass String[] to Object[] in method argument such as

anyArrayType(new String[] {"a", "b"} );

void anyArrayType(Object[] o) { }

//void anyArrayType(Object o) { } // this one work

BUT...

It is working in variable assignment such as

Object[] o1 = new String[] {"a", "b"};
Object o2 = new String[] {"c", "d"};

thanks

[Charith Fernando]

what is the error you are getting? please post the compilation error if you're getting any....

[Deepak Bala]

Seems to work fine for me.

  
new test().arr(new String[] {"1"});
 
public void arr ( Object [] arr)
{
}
 
  

[Anthony Karta]

Sorry guys.

I tried with "primitive" type such as:

anyArrayType(new short[] {5,8});

why it works for Wrapper classes??

thanks again

[Barry Gaunt]

I think Anthony is asking about overloading here. Anthony do you mean having both anyArrayType method definitions at the same time?

[Barry Gaunt]

Originally posted by Anthony Karta:
Sorry guys.

I tried with "primitive" type such as:

anyArrayType(new short[] {5,8});

why it works for Wrapper classes??

thanks again

It works because arrays of wrapper class objects are arrays of Objects too.

[Anthony Karta]

Originally posted by Barry Gaunt:


It works because arrays of wrapper class objects are arrays of Objects too.

well, I'm expecting short[] array will be autoboxed to Short[] by JVM, but the code even not compile.

do more testing:

short[] shortArray = new short[] {5,8} ;

Object[] oo = (Short[]) shortArray; // Not compiled here

how to convert primitive array to Wrapper array then?

this whole array thing make me confuse. Seems autoboxing doesn't work the same way as non-array reference variable, such as below:

short shortVar = 5;
Short shortWrapper = shortVar; // worked !

[Barry Gaunt]

What you are expecting is not possible. A short[] will not be autoboxed into a Short[]. Autoboxing only applies to the primitive and its corresonding wrapper class (eg. short -> Short).