اختيار عنصر عشوائي

public class Program {
    public static void main(String []args) throws Exception {
        Program context = new Program();
    }
    public Program() throws Exception {
        int count = 5;
        RandListPicker picker = new RandListPicker(count);
        String[] list = { "item 1", "item 2", "item 3", "item 4", "item 5" };
        for (int i = 0; i < count; i++) {
            int index = picker.getNewRandomIndex();
            String item = list[index];
            System.out.println(item);
        }
        System.out.println("end");
    }
}
class RandListPicker {
    private int count;
    private int countUnvisited;
    private int[] unvisitedIndexes;
    public RandListPicker(int count) {
        this.count = count;
        this.initIndexes();
    }
    public void initIndexes() {
        this.countUnvisited = this.count;
        this.unvisitedIndexes = new int[count];
        for (int i = 0; i < this.count; i++) this.unvisitedIndexes[i] = i;
    }
    public int getNewRandomIndex() throws Exception {
        if (this.countUnvisited <= 0) {
            throw new Exception("all indexes has visited");
        }
        int index = (int) (Math.random() * this.countUnvisited);
        int newIndex = this.unvisitedIndexes[index];
        this.unvisitedIndexes[index] = this.unvisitedIndexes[--this.countUnvisited];
        return newIndex;
    }
}