problem in array assignment

[rohit shekhar]

we can do the following assignment without any error :

class a
{
           public static void main(String[] args)
           {
                       int[] a = new int[5];
                       a[0]='b';                  // assigning value other that integer
           }
}

but it gives error in the following code

class a
{
            public static void main(String[] args)
            {
                      int[] a;
                      char[] b = new char[5];
                      a=b;
            }
}

[Jim Hoglund]

Your two examples are not at all the same - kind of an
apples versus teeth comparison.

Jim ... ...

[Harpreet Singh janda]

Primitives and primitive array behaves in different manner.

You can't assign one type of primitive array to other type of array but you can assign one type of primitive to other type of primitive (with some restrictions).

So when you are writing a[0]='b' this means you are assigning a value to 0th location of the array and it is legal because. int i = 'b' is legal but assigning a char array to int array reference is not legal.

[Prithvi Sehgal]

Hi,

Character values can implicitly promoted to integers. But that is not the case with array references itself.
Assignment a character value to an integer and assigning a character array to an integer or vice versa
are two entirely different scenario's.

Best Regards,

[Stephen Davies]

Jim Hoglund wrote:Your two examples are not at all the same - kind of an
apples versus teeth comparison.

Jim ... ...

Absolutely, and here you are trying to assign an array of type a to an array of type b. Array objects are not the same as primitives! In fact the behavior is common to most objects, for example the wrapper classes.

[Henry Wong]

Jim Hoglund wrote: kind of an apples versus teeth comparison.

Interesting turn of phrase...

Henry

[Rajeev Rnair]

Both array types are different. You cannot assigna char[] to an int[]. However you can assign a char value to an int. Also you can assign a int value to a char when the int value is 0<= i<= 65535! (Keep in mind char value ranges from 0 to 65535)
Also in your second code you are NOT initializing the local variable int[] a. Local variables should be initialized before you start using it!

        int[] a = new int[5];   
        char[] b = new char[5];   
        
        int i = 'a';     // ok
        char c = 4;   // ok
        char c = 65536; // COMPILE ERROR
        
         a[0] = b[0]; // WORKS FINE
        //b[0] = a[0]; // COMPILE ERROR (you figure out WHY  :) )

hope this is clear!