练习使用集合

for(Map.Entry<String, Object> pair : map.entrySet()){
    System.out.println(pair.getKey() + " - " + pair.getValue());
}

Set <Map.Entry<String,String>> setentrys=map.entrySet();

Set <String> setkeys=map.keySet();

Set <String> setvalues=map.values();

Iterator<Map.Entry<String,String>> iteratorentry =map.entrySet().iterator();

Iterator<String> iteratorkey = map.keySet().iterator();

Iterator<String> iteratorvalues =map.values().iterator();