A given array of objects can be one-dimensional, two-dimensional, three-dimensional, or n-dimensional. How can you tell? In this tip, the function getDim(Object o) takes an object and finds out it’s dimension. The length is calculated from an in-built static method Array.getLength(o).

There are instances when you need to represent an n-dimensional array to a linear array. That’s when you actually need to find out the dimension and length of an array so as to derive at a generic formula for conversion. Conversion in a “SPARSE MATRIX” is a typical example.

Here’s the code:

import java.lang.reflect.*;public class Reflec{    public static int getDim(Object array) {        int dim = 0;        Class cls = array.getClass();        while (cls.isArray()) {            dim++;            cls = cls.getComponentType();        }        return dim;    }  public static void main(String[] args){    Object o = new int[1][2][3];    // Get length    int len = Array.getLength(o);  //Will Output 1    // Get dimension    int dim = getDim(o);  //Will Output  3    System.out.println("Len : " + len + ", Dim : " + dim);  }}