Why does the toString method in java not seem to work for an array

Question

I want to convert a character array to a string object using the toString() method in java. Here is a snippet of the test code I used:

import java.util.Arrays; class toString{     public static void main(String[] args){         char[] Array = {'a', 'b', 'c', 'd', 'e', 'f'};         System.out.println(Array.toString());         } } 

In principle, it should print abcdef, but it is printing random gibberish of the likes of [C@6e1408 or [C@e53108 each time the program executes. I don't need an alternative out of this but want to know why this is happening.

Answer 1

To get a human-readable toString(), you must use Arrays.toString(), like this:

System.out.println(Arrays.toString(Array)); 

Java's toString() for an array is to print [, followed by a character representing the type of the array's elements (in your case C for char), followed by @ then the "identity hash code" of the array (think of it like you would a "memory address").

This sad state of affairs is generally considered as a "mistake" with java.

See this answer for a list of other "mistakes".

Answer 2

I don't know where you get the idea that "in principle" it should print "abcdef". Where is that documented?

Something like [C@6e1408 is certainly not random gibberish - it's the same way of constructing a string from an object as any other type that doesn't override toString() inherits - it's a representation of the type ([ indicating an array; C indicating the char primitive type) followed by the identity hash code in hex. See the documentation for Object.toString() for details. As it happens, arrays don't override toString.

If you want [a, b, c, d, e, f] you can use Arrays.toString(char[]). If you want abcdef you can use new String(char[]).