Find the dimension of array

but I want result in following format for arr it should be 2x2 and arr1 3x2

You should know, that in java you can do this:

Integer[][] arr = { { 1, 2 }, { 1, 3, 4, 5 } };

So the code below doesn't work for jagged arrays.

Also it doesn't work for 0-length arrays such as:

new boolean[11][0][4]

Here the code is:

public static void printDimension(Object array) {
    if (array == null) {
        System.out.println("Object is null!");
        return;
    }

    if (!array.getClass().isArray()) {
        System.out.println("Object is not array!");
        return;
    }

    String ans = "";
    Object cur = array;
    while (cur != null && cur.getClass().isArray()) {
        ans += "x" + Array.getLength(cur);

        if (!cur.getClass().getComponentType().isPrimitive()) {
            cur = ((Object[]) cur)[0];
        } else {
            break;
        }
    }

    System.out.println(ans.substring(1));
}

Example of usage:

printDimension(new boolean[1][11]);
printDimension(new boolean[1][11][4]);
printDimension(new Integer[14][88]);

Output:

1x11
1x11x4
14x88

2-D array is a array of arrays. So each array can have variable length (which represents columns in case of 2-D array). You can get length of individual arrays using

args[0].length;
args[1].length;  

and so on

and length of whole 2-D array using

args.length  

which is number of rows in 2-D array.

Related question: Multi-Dimension length array reflection java

you can use Array.lenght to know the lenght .. and by using this you can find the dimension . for example

    int xx = arr.length;  // will return the number of row
    int yy = arr[0].length;  // will return the number of column

N.B. assuming that every row has same number of columns

You can find the dimensions of an array using recursion and reflection.

Given the method dimensions:

private int dimensions(Class arrayType)
{
  return arrayType.isArray() ? 1 + dimensions(arrayType.getComponentType()) : 0
}

When calling the dimensions method like this:

int[] oneDimensionalArray = new int[0];
int[][] twoDimensionalArray = new int[0][0];
int[][][] threeDimensionalArray = new int[0][0][0];

System.out.println(dimensions(oneDimensionalArray.getClass()));
System.out.println(dimensions(twoDimensionalArray.getClass()));
System.out.println(dimensions(threeDimensionalArray.getClass()));

Will print:

1
2
3

I think you are asking obj is single dimension or double dimension or ... of array type.

private static void printDimension(Object arr) {
    final String className = arr.getClass().toString();
    Pattern pattern = Pattern.compile("([\\[])");
    Matcher matcher = pattern.matcher(className);
    int count = 0;
    while (matcher.find()) count++;
    int length = count>1?((Object[][])arr)[0].length:0;
    System.out.println("given object dimension:"+count+"x"+length);
}

...

Integer[][][] arr = new Integer[3][2][2];
printDimension(arr);
Integer[] arr1 = {};
printDimension(arr1);
printDimension(new Object());

result :

given object dimension:3x2
given object dimension:1x0
given object dimension:0x0