Contains Duplicate

//Given an array of integers, find if the array contains any duplicates. Your function should return true if any value appears at least twice in the array, and it should return false if every element is distinct.
import java.util.*;

public class LeetCode1 {

    public static void main(String[] args) {
        int[] arr = { 1, 2, 4, 1, 34 };
        System.out.println(containsDuplicate(arr));

    }

    public static boolean containsDuplicate(int[] nums) {

        Arrays.sort(nums);
        int[] arr = new int[nums.length - 1];
        for (int i = 0; i < nums.length - 1; i++)

        {
            arr[i] = nums[i + 1] - nums[i];
            if (arr[i] == 0)
                return true;

        }
        return false;
    }

}