content: package com.lvrenyang.pdf417;
  
  import java.util.Arrays;
  
  public class ArrayUtil {
  
      private ArrayUtil() {}
  
      /**
       * Finds a needle in an (unsorted) haystack.
       * @param haystack
       * @param needle
       * @return the key for the needle, or -1 if the needle doesn't exist in the haystack
       */
      public static int search(int[] haystack, int needle) {
          if (haystack == null) {
              throw new IllegalArgumentException("Haystack is null and cannot be searched");
          }
  
          for (int i = 0; i < haystack.length; i++) {
              if (haystack[i] == needle) {
                  return i;
              }
          }
          return -1;
      }
  
  
      public static int[] reverse(int[] input) {
          int[] reversed = new int[input.length];
          for (int i = input.length-1, j=0; i >= 0; i--, j++) {
              reversed[j] = input[i];
          }
          return reversed;
      }
  
      public static int[] fill(int size, int i) {
          int[] array = new int[size];
          Arrays.fill(array, i);
          return array;
      }
  
      public static int[] toIntegerArray(String row) {
          char[] chars = row.toCharArray();
          int[] ints = new int[chars.length];
          for (int i = 0; i < chars.length; i++) {
              ints[i] = Integer.parseInt("" + chars[i]);
          }
          return ints;
      }
  }
  