String is not equal to string?

Question

String[] letters  = {"A", "B", "C", "D", "E", "F", "G", "H", "I", "L"};

Scanner inp = new Scanner(System.in);
String input = (inp.nextLine());
String[] cord = input.split("");

for(int x = 0; x < 10; x++)
    if(letters[x] == cord[1])
        System.out.println("Fk yeah!");

Why the Fk yeah! never happens if I input one of A-L letters?

Are you sure `cord` is actually just the letter and no whitespace? — , Aug 20 '11 at 00:43
possible duplicate of [What is the difference between .Equals and ==](http://stackoverflow.com/questions/772953/what-is-the-difference-between-equals-and) — Michael Petrotta, Aug 20 '11 at 00:50

score 24 · Accepted Answer · answered Aug 20 '11 at 00:44

24

Strings are objects. The == compares objects by reference, not by their internal value.

There are 2 solutions:

Use String#equals() method instead to compare the value of two String objects.
```
if (letters[x].equals(cord[1]))
```

Use char instead of String. It's a primitive, so == will work.

char[] letters  = {'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'L'};

Scanner inp = new Scanner(System.in);
String input = (inp.nextLine());
char[] cord = input.toCharArray();

for (int x = 0; x < 10; x++)
    if (letters[x] == cord[1])
        System.out.println("Fk yeah!");

answered Aug 20 '11 at 00:44

BalusC

1,082,665
372
3,610
3,555

5

holy cow you have a lot of badges – Aug 20 '11 at 00:47
2

@Code: It's nothing when compared to Jon Skeet. – BalusC Aug 20 '11 at 00:48
well congrats either way :) I bow to you Sir – Aug 20 '11 at 00:53
@BalusC - does the `#` notation in `String#equals()` mean its an instance method? – Paul Bellora Aug 20 '11 at 01:44
@Kublai: Nothing special. I tend much to use javadoc style to refer the classname/methodname in written text (as one would normally do in javadocs). – BalusC Aug 20 '11 at 03:48

score 11 · Answer 2 · answered Aug 20 '11 at 00:46

To compare Strings for equality, don't use ==. The == operator checks to see if two objects are exactly the same object. Two strings may be different objects, but have the same value (have exactly the same characters in them). Use the .equals() method to compare strings for equality. Similarly, use the .compareTo() method to test for unequal comparisons. For example,

String s = "something", t = "maybe something else";
if (s == t)      // Legal, but usually WRONG.
if (s.equals(t)) // RIGHT
if (s > t)    // ILLEGAL
if (s.compareTo(t) > 0) // CORRECT>

String is not equal to string?

2 Answers2

Linked

Related