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Java Program to Find the Frequency of Character in a String

To understand this example, you should have the knowledge of the following Java programming topics:

Example: Find Frequency of Character


              

public class Frequency {

    public static void main(String[] args) {
        String str = "This website is awesome.";
        char ch = 'e';
        int frequency = 0;

        for(int i = 0; i < str.length(); i++) {
            if(ch == str.charAt(i)) {
                ++frequency;
            }
        }

        System.out.println("Frequency of " + ch + " = " + frequency);
    }
}

Output


              

Frequency of e = 4

In the above program, the length of the given string, str, is found using the string method length().

We loop through each character in the string using charAt() function which takes the index (i) and returns the character in the given index.

We compare each character to the given character ch. If it’s a match, we increase the value of frequency by 1.

In the end, we get the total occurrence of a character stored in frequency and print it.