Collection類及常用API

Collection類及常用API

Collection—類集工具類，定義了若干用於類集和映射的算法，這些算法被定義為靜態方法，具體查看api文檔;

a)  public static void sort(List<T> liet)

b)  public static int binarySearch(List<T> list,T key)

c)  public static void reverse(List<?> list)

d)  public static void shuffle(List<?> list)

e)  public static void swap(List<?> list,int i,int j)

f)   public static <T> void fill(List<? super T> list,T obj)

         List<String> nList=new ArrayList<String>();
         nList.add("zhangsan");
         nList.add("lisi");
         nList.add("wangwu");
         nList.add("zhaoliu");
         nList.add("tianqi");
         System.out.println("操作前");
         for(String s:nList){
             System.out.print(s+" ");
         }
         
         System.out.println();
         System.out.println("交換順序後");
         Collections.swap(nList,1,2);
         for(String s:nList){
             System.out.print(s+" ");
         }
         
         System.out.println();
         System.out.println("自然排序後");
         Collections.sort(nList);
         for(String s:nList){
             System.out.print(s+" ");
         }
         
         System.out.println();
         System.out.println("二分法查找");
         System.out.println(Collections.binarySearch(nList, "zhaoliu"));
         
         System.out.println("打亂順序");
         Collections.shuffle(nList);
         for(String s:nList){
             System.out.print(s+" ");
         }
         
         System.out.println();
         System.out.println("填充");
         Collections.fill(nList, "jay");
         for(String s:nList){
             System.out.print(s+" ");
         }

輸出結果：

操作前

zhangsan lisi wangwu zhaoliu tianqi

交換順序後

zhangsan wangwu lisi zhaoliu tianqi

自然排序後

lisi tianqi wangwu zhangsan zhaoliu

二分法查找

4

打亂順序

zhaoliu tianqi wangwu zhangsan lisi

填充

jay jay jay jay jay