Java Array deepToString() method Code With Examples

Program

import java.util.Arrays;
public class ArrayDeepToString
{
    public static void main(String[] args)
    {
        int[][] mat = new int[2][2];
        mat[0][0] = 99;
        mat[0][1] = 151;
        mat[1][0] = 30;
        mat[1][1] = 5;
        System.out.println(Arrays.deepToString(mat));
    }
}

Output

[[99, 151], [30, 5]]

Description

public static String deepToString​(Object[] a)

Returns a string representation of the “deep contents” of the specified array. If the array contains other arrays as elements, the string representation contains their contents, and so on. This method is designed for converting multidimensional arrays to strings.
The string representation consists of a list of the array’s elements, enclosed in square brackets (“[]”). Adjacent elements are separated by the characters “, ” (a comma followed by a space). Elements are converted to strings as by String.valueOf(Object), unless they are themselves arrays.

If an element e is an array of a primitive type, it is converted to a string by invoking the appropriate overloading of Arrays.toString(e). If an element e is an array of a reference type, it is converted to a string by invoking this method recursively.

To avoid infinite recursion, if the specified array contains itself as an element, or contains an indirect reference to itself through one or more levels of arrays, the self-reference is converted to the string “[…]”. For example, an array containing only a reference to itself would be rendered as “[[…]]”.

This method returns “null” if the specified array is null. Q

Parameters:

a – the array whose string representation to return

Returns:

a string representation of a

Since:

1.5