Re: Multidimensional arrays and arrays of arrays
Philipp wrote:
Hello
How can I distinguish if an array is multidimensional of if it just
contains an array? Or put it another way how can I tell at runtime
whether a/b in the example below is an array containing an array, or
if it is a multidimensional array.
If I know beforehand exactly which type it is, I can use instanceof
(see example), but I don't (especially the number of dimensions, I
don't know).
Else I can call getClass().getName() on the object and see if it
starts with "[[" (pretty ugly IMHO).
Is there another, cleaner method to do this?
public static void main(String[] args) {
Object[] a = new Object[1];
a[0] = new float[12];
Object b = new float[1][12];
if(a instanceof float[][]){
System.out.println("a is float[][]");
}
if(b instanceof float[][]){
System.out.println("b is float[][]");
}
}
prints "b is float[][]" (but not for a) as expected.
Phil
There is no difference between a multidimensional array, and an array of
arrays. They are the same thing. Java provides a little syntactic sugar
for allocation a uniform array of arrays (of arrays etc...), but there
is no other difference, and no way to tell, other than testing each
element of every array of arrays.
--
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