/*
 * Collections的sort排序
 */
public class ListDemo {
	
	public static void main(String[] args) {
		List<String> ars = new ArrayList<>();
		for(int i=0;i<4;i++) {
			ars.add(String.valueOf(i));
			}
		ars.add("2");
		System.out.println(ars);  //[0, 1, 2, 3, 2]
		//正序排序
		Collections.sort(ars);
		System.out.println(ars);  //[0, 1, 2, 2, 3] 正序
		//用比較器
		Collections.sort(ars, new Comparator<String>() {

			@Override
			public int compare(String o1, String o2) {
				
				return o2.compareTo(o1);  //正常應該o1.compareTo(o2),相反
			}
		});
		System.out.println(ars); //[3, 2, 2, 1, 0]
		//reverse 反轉指定列表中元素的順序
		Collections.reverse(ars);
		System.out.println(ars); // [0, 1, 2, 2, 3]
	}
}