Find duplicate characters in a String and count the number of occurances using Java

Question

How can I find the number of occurrences of a character in a string?

For example: The quick brown fox jumped over the lazy dog.

Some example

Answer 1

A better way would be to create a Map to store your count. That would be a Map

You need iterate over each character of your string, and check whether its an alphabet. You can use Character#isAlphabetic method for that. If it is an alphabet, increase its count in the Map. If the character is not already in the Map then add it with a count of 1.

NOTE: - Character.isAlphabetic method is new in Java 7. If you are using an older version, you should use Character#isLetter

    String str = "asdfasdfafk asd234asda";
    Map charMap = new HashMap();
    char[] arr = str.toCharArray();

    for (char value: arr) {

       if (Character.isAlphabetic(value)) {
           if (charMap.containsKey(value)) {
               charMap.put(value, charMap.get(value) + 1);

           } else {
               charMap.put(value, 1);
           }
       }
    }

    System.out.println(charMap);

OUTPUT: -

{f=3, d=4, s=4, a=6, k=1}