How do I apply the for-each loop to every character in a String?

Question

So I want to iterate for each character in a string.

So I thought:

for (char c : \"xyz\")

but I get a compiler error:

Answer 1

String s = "xyz";
for(int i = 0; i < s.length(); i++)
{
   char c = s.charAt(i);
}

 

Answer 2

Unfortunately Java does not make String implement Iterable<Character>. This could easily be done. There is StringCharacterIterator but that doesn't even implement Iterator... So make your own:

public class CharSequenceCharacterIterable implements Iterable<Character> {
    private CharSequence cs;

    public CharSequenceCharacterIterable(CharSequence cs) {
        this.cs = cs;
    }

    @Override
    public Iterator<Character> iterator() {
        return new Iterator<Character>() {
            private int index = 0;

            @Override
            public boolean hasNext() {
                return index < cs.length();
            }

            @Override
            public Character next() {
                return cs.charAt(index++);
            }
        };
    }
}

Now you can (somewhat) easily run for (char c : new CharSequenceCharacterIterable("xyz"))...

Answer 3

You need to convert the String object into an array of char using the toCharArray() method of the String class:

String str = "xyz";
char arr[] = str.toCharArray(); // convert the String object to array of char

// iterate over the array using the for-each loop.       
for(char c: arr){
    System.out.println(c);
}