that way, object users can t do things they are not supposed to do, access data they are not supposed to access, and generally be a pest 在這種方式下,對(duì)象用戶無(wú)法做不準(zhǔn)他們做的事,無(wú)法訪問(wèn)不準(zhǔn)他們?cè)L問(wèn)的數(shù)據(jù),并且通常是有害數(shù)據(jù)。
is essentially a placeholder interface that specific command implementations implement for the purpose of allowing the command objects users to pass-in parameters that are specific to that command implementation 本質(zhì)上是一個(gè)占位符接口,這個(gè)特定的command實(shí)現(xiàn)的目的是允許command對(duì)象的用戶傳入特定于這個(gè)command實(shí)現(xiàn)的參數(shù)。