????2.????ConcurrentHashMap
??????1??ConcurrentHashMap???????
????ConcurrentHashMap?????map?????????????????????????????????????????????ò?????????????ConcurrentHashMap?????????????????????????16?????????????????????????á?
??????2??ConcurrentHashMap??????????
????HashTable???????????????????????Ч????￡?????????з???HashTable?????????????????????????????ж??????????????????????????????????????????????????????????????ε??????????????????????????????????Ч??????????Ч???????ConcurrentHashMap??????????μ?????????????????????ε?洢????????????????????????????????????????????????????????????????ε????????????????????

?????????????????????磩?????????HashTable?????????????????hash?????????????ConcurrentHashMap??????????????????????????hash???????????????????????????????????????hashTable??ζ??????????????ConcurrentHashMap????????????????? ?????
????ConcurrentHashMap??hash????16?????????????????get??put??remove????ò????????????????????????????????????????????????16??????????????????????????????
??????3??ConcurrentHashMap??remove????
????????ConcurrentHashMap????remove???????????????м????????????

????????????????ConcurrentHashMap?????segment??????????е???????remove?????磬??????C??C?????????б???????????C??????????????????μ??????У?C??????????????????????????????????????????????д???????????磬???????????????????A???д????C???????????????????????????????????????????????????C??????????????D????????????????
????????????????????ConcurrentHashMap???????????????????????????????Ч?????????е?????????????ConcurrentHashMap?????????????????????