You can not change the dimension of an array in the same
 sense that suggest that you can not change the value of
 the number 3.

 You can, however, create a new array with another dimension
 at run-time.

 The following example code shows how to create and populate an
 array, when the dimension becomes only known at run-time.

 In this example, an array with 3 dimensions of sizes 4, 5, and
 6, respectively, is created, filled, and printed.

public class Main
{
 public static int[] cdr( final int[] list )
 { return java.util.Arrays.copyOfRange( list, 1, list.length ); }

 public static java.lang.Object build( final int ... extensions )
 { final java.lang.Object array = java.lang.reflect.Array.newInstance
   ( java.lang.Integer.TYPE, extensions );  
   for( int i = 0; i < extensions[ 0 ]; ++i )if( extensions.length > 1 )
   java.lang.reflect.Array.set( array, i, build( cdr( extensions )));
   else java.lang.reflect.Array.setInt(( int[] )array, i, i );
   return array; }

 public static void print( final java.lang.Object array )
 { for( int i = 0; i < java.lang.reflect.Array.getLength( array ); ++i )
   if( array.getClass().getName().startsWith( "[[" ))
   print( java.lang.reflect.Array.get( array, i )); else
   java.lang.System.out.print( java.lang.reflect.Array.getInt( array, i )); }
   
 public static void main( final java.lang.String[] args )
 { print( build( 4, 5, 6 )); }}

The reason the array isn't changed is that object references are passed by
value. So when you assign a new array to the formal parameter myArray2
inside changeDimMyArray(), the array reference myArray in main() is not
affected at all. So you can't "change the dim of array from inside the
method". But you can easily do something nearly as good: change the
changeDimMyArray() method to return the redimensioned array. It might look
something like this:

public void changeDimMyArray(int myArray[][])
{
   // figure out the desired new array sizes

   myNewArray = new int[newRow][newCol];

   // do more stuff, like copy values from myArray to myNewArray

   return myNewArray;
}

Then, back in main, you can call it like this:

myArray = changeDimMyArray(myArray);

That will change the object to which myArray refers. Bear in mind that
unless you've assigned the original array reference to another variable, the
original array will be beyond reach of your program and headed for the
garbage collector.

Hope this helps,

Ted Hopp
ted@zigzagworld.com