List<String> list =newArrayList<String>();
list.add("aaaa");//编译时检查
//泛型集合存取
List<String> list =newArrayList<String>();
list.add("aaaa");
list.add("bbbb");
list.add("cccc");
Iterator<String> it = list.iterator();while(it.hasNext()){
String value = it.next();}for(String s : list){
System.out.println(s);}
Map<Integer,String> map =newHashMap<Integer,String>();
map.put(1,"aa");
map.put(2,"bb");
map.put(3,"cc");
Set<Map.Entry<Integer,String>> set = map.entrySet();
Iterator<Map,Entry<Integer,String>> it =
set.iterator();while(it.hashNext()){
Map.Entry<Integer,String> entry = it.netx();int key = entry.getKey();
String value = entry.getValue(;}for(Map.Entry<Integer,String> entry : map.entrySet()){int key = entry.getKey();
String value = entry.getValue(;}