package test2;import  java.util.*;import static java.lang.System.out;public class test2 extends StaticSuper{        //put输入,get,得到    static void mapTest(){        // TODO 自动生成的方法存根        HashMap<String, String> map = new HashMap<String, String>();                map.put("1", "a1");        map.put("2", "a2");        map.put("3", "a3");                        //遍历的方法一、缺点，费时        Iterator<String> iterator = map.keySet().iterator() ;        while (iterator.hasNext()){            //Object key = iterator;             Object key = iterator.next();             System.out.print("Key = " + key);            System.out.println(", Value = "http://www.mamicode.com/+map.get(key));            //iterator.next();        }                //遍历的方法二，省时        Iterator entries = map.entrySet().iterator();          while(entries.hasNext()){            Map.Entry entry = (Map.Entry) entries.next();              Object key =  entry.getKey();              Object value = entry.getValue();              System.out.println("Key = " + key + ", Value = "http://www.mamicode.com/+ value);          }                System.out.println("map end!");    }        static void setTest(){        Set<String> set1 = new HashSet<String>();        set1.add("s1_1");        set1.add("s1_2");        set1.add("s1_3");        set1.add("one");                System.out.println(set1);                Set<String> set2 = new HashSet<String>();        set2.add("s2_1");        set2.add("s2_1");        set2.add("s2_3");        set2.add("one");                System.out.println(set2);                Set<String> sn = new HashSet<String>(set1);        sn.retainAll(set2);        System.out.println(sn);    }        public static void main(String[] args) {            }}