Getting Index of a char from a char array

Question

Hello I need to get a char's index form a char array (By not using String). Yes I know it is unreasonable to do it while there is String but I need to know how to do it. So, I would appreciate that if you could show understanding.

My char array holds:

" ABCDEF"

(It has a space at the beginning).

When I try this: (I have already imported java.util.Arrays;)

Arrays.toString(charArr).indexOf(charNeeded);

It returns 16 because:

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

Prints [ , A, B, C, D, E, F], it means the String that is being returned(index being searched in) is that. I need to search the index on " ABCDEF" can anyone help?

Thanks in advance.

Possible duplicate of [Where is Java's Array indexOf?](https://stackoverflow.com/questions/4962361/where-is-javas-array-indexof) — Logan, Jun 05 '18 at 08:36
instead of using `Arrays.toString(charArr).indexOf(charNeeded);` use `new String(charArr).indexOf(charNeeded);` — Ashwin K Kumar, Jun 05 '18 at 08:39

score 7 · Accepted Answer · answered Jun 05 '18 at 08:39

If you can't convert it to a string and use indexOf:

int found = new String(charArr).indexOf(charNeeded)

then you would need to use a loop:

int found = -1;
for (int i = 0; i < charArr.length; ++i) {
  if (charArr[i] == charNeeded) {
    found = i;
    break;
  }
}

Or, if you want to use a very over-the-top solution, using streams:

int found =
    IntStream.range(0, charArr.length)
        .filter(i -> charArr[i] == charNeeded)
        .findFirst()
        .orElse(-1);

Thank you for your understanding and kinid answer I think this would work. — BUY, Jun 05 '18 at 10:11

Getting Index of a char from a char array

1 Answers1