Random english letter generator according to their frequencies in English.

FrequentLetterGenerator.java

package com.safaorhan.example;

public class FrequentLetterGenerator {
    private static char[] letters = "ABCDEFGHIJKLMNOPQRSTUVWXYZ".toCharArray();
    private static float[] weights = new float[]{
            8.167f,
            1.492f,
            2.782f,
            4.253f,
            12.702f,
            2.228f,
            2.015f,
            6.094f,
            6.966f,
            0.153f,
            0.772f,
            4.025f,
            2.406f,
            6.749f,
            7.507f,
            1.929f,
            0.095f,
            5.987f,
            6.327f,
            9.056f,
            2.758f,
            0.978f,
            2.361f,
            0.150f,
            1.974f,
            0.074f};

    public static char generate() {
        float totalWeight = 0f;
        for (int i = 0; i < letters.length; i++) {
            totalWeight += weights[i];
        }

        int randomIndex = -1;
        float random = (float) (Math.random() * totalWeight);
        for (int i = 0; i < letters.length; i++) {
            random -= weights[i];
            if (random <= 0.0d) {
                randomIndex = i;
                break;
            }
        }

        return letters[randomIndex];
    }
}