java 数组去重

1.数组去重  用list 或者直接hashset 不重复的特性 

2. 值得注意的是 list.toarry(String[]),用这个带参数的方法比较方便，如果不带参数 容易报错。

public class arrays {
	public static void main(String[] args) {
		String[] arr= {"ali","baidu","zj","whx","ali","lmx","zj","jxp","whx","wxc","wxc"};
		String[] sl =arrays.arrDeleteOne(arr);
		System.out.println("数组去重之 利用 list");
		for (String string : sl) {
			System.out.printf(string+" ");
		}
		System.out.println(" ");
		String[] s2 =arrays.arrDeleteTwo(arr);
		System.out.println("数组去重之 利用 set");
		for (String string : s2) {
			System.out.printf(string+" ");
		}
 
	}
   /*
   * @me  数组去重 -list
    */
	public static String[] arrDeleteOne(String [] arr) {
	  ArrayList list = new ArrayList();
	  String[] newarray = new String[list.size()];
	  for (String ar : arr) {
		if(!list.contains(ar)) {
			list.add(ar);
		}
		
	}
	return     list.toArray(newarray);
	}
	   /*
	   * @me  数组去重 -set
	    */
		public static String[] arrDeleteTwo(String [] arr) {
			HashSet set = new HashSet();
		  ArrayList list = new ArrayList();
		  String[] newarray = new String[list.size()];
		  for (String ar : arr) {
			 set.add(ar);
			
		}
		return     set.toArray(newarray);
		}
//		  /*
//		   * @me  数组去重 -  用一个数组   这个方法暂时行不通
//		    */
//  public static String[] arrDeleteThree(String [] arr) {
//				 for (int i=0; i< arr.length; i++) {
//					     if(arr[i] == null) {
//						            break;
//					     }
//					for(int j = i+1;j