number of unique items in array code example

Example 1: how to create an array with unique values

import java.util.Random;

public class GenRandArray {
    //Recommend reseeding within methods
    static Random rand = new Random();

    public static void fillInt( int[] fillArray ) {
        //seeds the random for a new random each method call
        rand.setSeed(System.currentTimeMillis());
		
        for(int i = 0; i < fillArray.length; i++)
        {
            fillArray[i]= rand.nextInt();
            
          	/* for loop to check to make sure that none of the previous
               numbers added are the same as the one just added. */
            for (int j = 0; j < i; j++)
            {
              	/* if so we need to redo the last random number by
              	   moving i back one index to be re-set */
                if (fillArray[i] == fillArray[j])
                {
                    i--;
                }
            }
        }
    }
}

Example 2: unique numbers in array

import java.util.ArrayList;

public class UniqueNumbersInArray {

    public static void main(String[] args) {


    int arr[] = { 4,5,5,4,5,6,5,8,4,7};

        ArrayList<Integer> uniqueArr = new ArrayList<Integer>();
        for (int i = 0; i < arr.length; i++) {

            int k = 0;
            if (!uniqueArr.contains(arr[i])){
                uniqueArr.add(arr[i]);
                k++;

                for (int j = i; j < args.length ; j++) {
                    if (arr[i]==arr[j]){
                        k++;
                    }
                }

                System.out.println(arr[i]);
                System.out.println(k);
            }

        }
    }
}