????3??????

????3.1 ????????HashMap

????1????????key??value???keySet??entrySet??????????????????key???????????縴??????????????????????????????????????HashMap????value???????entrySet???????????? key??value???????????????????????????С??HashMap????value????????entrySet???????????????????????????????????У???key????????????????keySet????????????Ч???????entrySet??10%???????????????????entrySet???????key?????????????????????keySet?????????????????key????????entrySet??????????????????????????????????????????????????

????2???????key???keySet???????????????entrySet???????value????????????????????????????????????У?keySet??entrySet?????????23%??

????3???????value??????vlaues??????????entrySet???????keySet??????

????4???????????д???У???????????д??????Ч??????Щ??

for (String key : map.keySet()) {
    value = map.get(key);
}

for (Entry<String?? String> entry: map.entrySet()) {
    key = entry.getKey();
    value = entry.getValue();
}

for (String value : map.values()) {
}

????3.2 ????????TreeMap

????1????????key??value?????HashMap?????entrySet????????????keySet????????TreeMap????Ч??????????????TreeMap????value???????????????entrySet????????????key??value???????????????TreeMap??????????entrySet??????

????2???????key???keySet???????????????entrySet???????value????????????????????????????????????У?keySet??entrySet?????????24%??

????3???????value??????vlaues??????????entrySet?????????keySet??????

????4???????????д???У???????????д??????Ч??????Щ??

for (String key : map.keySet()) {
    value = map.get(key);
}

for (Entry<String?? String> entry: map.entrySet()) {
    key = entry.getKey();
    value = entry.getValue();
}

for (String value : map.values()) {
}