????Socket????????????Socket????????????????????????????????????????????????????????????????????????P2P??????????Socket???????????????????TCP/IP??Socket???????????д????????/??????????
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????Unix?????????(IO)?????Open-Read-Write-Close??????????????????????????????IO?????????????????Open??????????????????????豸?????д??????????IO?????????????????????????????????????????λ??ε?????д???????Read??????????IO???????????????????????????????????Write??????????????????е?????????д????IO???????? ?????е?Read??Write?????????????????????????Close????????????IO???????á?
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??????????????????????socket???????????????????????е????socket????????????е??????socket???????????????ɡ???????????з??????????????????socket?д??????????????2??????Э?齫??Щ?????????????????????????socket?????????????????????????????????????????????????
????TCP??UDP???
????????socket????????????????Э??????????????????????????????????????
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?????????
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???????????????????????????????????????socket??????UDP????TCP????????????Э???socket???????????????????-??????????????ó?????????????????????TCP??UDPЭ??????????????????????????????????
??????UDP?У???η?????????????????????????socket?????????????socket??????????????TCP??????????Э?飬??????socket?????????????????????????????н???????????????????TCPЭ???socket????
??????UDP?У?????????????С????64KB?????????TCP???????????????????????TCP????socket???????????????????????????IO???????е?????????????????????
????UDP???????????Э?飬????????????????????????????????socket????????TCP?????????Э?顣????????????????????????????????μ??
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????Java?е?socket???
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????????????????????У??????????TCP/IPЭ???socket??????????Э??????UDP/IP????????????????е?socket??????λ??java.net???￡??????????????socket??????????????????
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????int port = 8919;
????Socket client = new Socket(host?? port);
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