Map的施用方式-iterator collections的使用
1 iteratorlai 来循环
1.1
public static void main(String[] args) {
// TODO Auto-generated method stub
Map map = new HashMap();
map.put("drink", "1");
map.put("hello", "3");
map.put("food", "2");
Iterator iterator = map.keySet().iterator();
while(iterator.hasNext()){
System.out.println(map.get(iterator.next()));
}
}
1.2
Set entries = map.entrySet( );
Iterator iterator = entries.iterator( );
while(iterator.hasNext( )) {
Map.Entry entry =(Map.Entry)iterator.next();
Object key = entry.getKey( );
Object value = entry.getValue();
System.out.println("Key:"+key);
System.out.println("/n"+entry); //food=2
}
2 Collections 得到最大最小值
Collection collection = map.values();//返回数值
Set sets= map.keySet();
System.out.println(Collections.max(sets));//key的最大值
Collection collection = map.values();
System.out.println(Collections.max(collection));//value的最大值