arr1 == arr2 is false why?

Question

The following:

class ArrayCompare 
{
    public static void main (String[] args) 
    {
        int []arr1 = {1, 2, 3, 4, 5};
        int []arr2 = {1, 2, 3, 4, 5};
        System.out.println("arr1 == arr2 is " + (arr1 == arr2));
    }
}

Returns arr1 == arr2 is false

Why is this? Why is arr1 Equals to arr2 is false.

Should this not be true?

The contents of the arrays are equal. But each one is a reference to a different object. — barak manos, Nov 10 '14 at 11:38
possible duplicate of [comparing arrays in java](http://stackoverflow.com/questions/5588460/comparing-arrays-in-java) — JJJ, Nov 10 '14 at 11:40
Off-site resource that has nice pictures that can really help to visualize this: http://www.javaranch.com/campfire/StoryPassBy.jsp — Gimby, Nov 10 '14 at 13:52

score 9 · Accepted Answer · answered Nov 10 '14 at 11:37

9

No it should not be true. You are comparing the references of two distinct objects, so == should return false.

Use Arrays.equals(arr1,arr2) if you wish to compare the contents of the two arrays.

answered Nov 10 '14 at 11:37

Eran

387,369
54
702
768

score 0 · Answer 2 · answered Nov 10 '14 at 11:37

0

Java eye is not human eye.

Though the content is same, since both references are pointing to difference Objects , == returns false.

System.out.println(Arrays.equals(arr1, arr2)); // prints true

answered Nov 10 '14 at 11:37

Suresh Atta

120,458
37
198
307

score 0 · Answer 3 · edited May 23 '17 at 12:00

0

You are trying to compare references of two different objects using == so therefore it returns false. To compare the contents use:

 Arrays.equals(arr1, arr2);

Also, might be worth reading the following Java == vs .equals() confusion

edited May 23 '17 at 12:00

Community

1
1

answered Nov 10 '14 at 11:39

Harry

3,031
7
42
67

score 0 · Answer 4 · answered Nov 10 '14 at 11:40

arr1.equals(arr2) is the same as arr1 == arr2, i.e. is it the same array, i.e. whether the references (pointers) are same. Use:

Arrays.equals(arr1, arr2);

to compare the contents of the arrays. This will return true if the two specified arrays of ints are equal to one another. So, use:

System.out.println("arr1 == arr2 is " + Arrays.equals(arr1, arr2));

arr1 == arr2 is false why?

4 Answers4