外文文献-the java io systemjava io 系统

毕业设计外文文献原文及译文THEJAVAI/OSYSTEMJAVAI/O系统学生姓名学号系别专业指导教师2015年5月电子与计算机科学技术系网络工程THEJAVAI/OSYSTEMCREATINGAGOODINPUT/OUTPUTI/OSYSTEMISONEOFTHEMOREDIFFICULTTASKSFORTHELANGUAGEDESIGNERTHISISEVIDENCEDBYTHENUMBEROFDIFFERENTAPPROACHESTHECHALLENGESEEMSTOBEINCOVERINGALLEVENTUALITIESNOTONLYARETHEREDIFFERENTSOURCESANDSINKSOFI/OTHATYOUWANTTOCOMMUNICATEWITHFILES,THECONSOLE,NETWORKCONNECTIONS,ETC,BUTYOUNEEDTOTALKTOTHEMINAWIDEVARIETYOFWAYSSEQUENTIAL,RANDOMSQLSERVER2000,BUFFERED,BINARY,CHARACTER,BYLINES,BYWORDS,ETCTHEJAVALIBRARYDESIGNERSATTACKEDTHISPROBLEMBYCREATINGLOTSOFCLASSESINFACT,THEREARESOMANYCLASSESFORJAVASI/OSYSTEMTHATITCANBEINTIMIDATINGATFIRSTIRONICALLY,THEJAVAI/ODESIGNACTUALLYPREVENTSANEXPLOSIONOFCLASSESTHEREWASALSOASIGNIFICANTCHANGEINTHEI/OLIBRARYAFTERJAVA10,WHENTHEORIGINALBYTEORIENTEDLIBRARYWASSUPPLEMENTEDWITHCHARORIENTED,UNICODEBASEDI/OCLASSESINJDK14,THENIOCLASSESFOR“NEWI/O,”ANAMEWELLSTILLBEUSINGYEARSFROMNOWWEREADDEDFORIMPROVEDPERFORMANCEANDFUNCTIONALITYASARESULT,THEREAREAFAIRNUMBEROFCLASSESTOLEARNBEFOREYOUUNDERSTANDENOUGHOFJAVASI/OPICTURETHATYOUCANUSEITPROPERLYINADDITION,ITSRATHERIMPORTANTTOUNDERSTANDTHEEVOLUTIONHISTORYOFTHEI/OLIBRARY,EVENIFYOURFIRSTREACTIONIS“DONTBOTHERMEWITHHISTORY,JUSTSHOWMEHOWTOUSEIT”THEPROBLEMISTHATWITHOUTTHEHISTORICALPERSPECTIVE,YOUWILLRAPIDLYBECOMECONFUSEDWITHSOMEOFTHECLASSESANDWHENYOUSHOULDANDSHOULDNTUSETHEMTHISCHAPTERWILLGIVEYOUANINTRODUCTIONTOTHEVARIETYOFI/OCLASSESINTHESTANDARDJAVALIBRARYANDHOWTOUSETHEMTHEFILECLASSBEFOREGETTINGINTOTHECLASSESTHATACTUALLYREADANDWRITEDATATOSTREAMS,WELLLOOKATAUTILITYPROVIDEDWITHTHELIBRARYTOASSISTYOUINHANDLINGFILEDIRECTORYISSUESTHEFILECLASSHASADECEIVINGNAMEYOUMIGHTTHINKITREFERSTOAFILE,BUTITDOESNTITCANREPRESENTEITHERTHENAMEOFAPARTICULARFILEORTHENAMESOFASETOFFILESINADIRECTORYIFITSASETOFFILES,YOUCANASKFORTHATSETUSINGTHELISTMETHOD,WHICHRETURNSANARRAYOFSTRINGITMAKESSENSETORETURNANARRAYRATHERTHANONEOFTHEFLEXIBLECONTAINERCLASSES,BECAUSETHENUMBEROFELEMENTSISFIXED,ANDIFYOUWANTADIFFERENTDIRECTORYLISTING,YOUJUSTCREATEADIFFERENTFILEOBJECTINFACT,“FILEPATH”WOULDHAVEBEENABETTERNAMEFORTHECLASSTHISSECTIONSHOWSANEXAMPLEOFTHEUSEOFTHISCLASS,INCLUDINGTHEASSOCIATEDFILENAMEFILTERINTERFACEADIRECTORYLISTERSUPPOSEYOUDLIKETOSEEADIRECTORYLISTINGTHEFILEOBJECTCANBELISTEDINTWOWAYSIFYOUCALLLISTWITHNOARGUMENTS,YOULLGETTHEFULLLISTTHATTHEFILEOBJECTCONTAINSHOWEVER,IFYOUWANTARESTRICTEDLISTFOREXAMPLE,IFYOUWANTALLOFTHEFILESWITHANEXTENSIONOFJAVATHENYOUUSEA“DIRECTORYFILTER,”WHICHISACLASSTHATTELLSHOWTOSELECTTHEFILEOBJECTSFORDISPLAYTHEDIRFILTERCLASS“IMPLEMENTS”THEINTERFACEFILENAMEFILTERITSUSEFULTOSEEHOWSIMPLETHEFILENAMEFILTERINTERFACEISPUBLICINTERFACEFILENAMEFILTERBOOLEANACCEPTFILEDIR,STRINGNAMEITSAYSALLTHATTHISTYPEOFOBJECTDOESISPROVIDEAMETHODCALLEDACCEPTTHEWHOLEREASONBEHINDTHECREATIONOFTHISCLASSISTOPROVIDETHEACCEPTMETHODTOTHELISTMETHODSOTHATLISTCAN“CALLBACK”ACCEPTTODETERMINEWHICHFILENAMESSHOULDBEINCLUDEDINTHELISTTHUS,THISSTRUCTUREISOFTENREFERREDTOASACALLBACKMORESPECIFICALLY,THISISANEXAMPLEOFTHESTRATEGYPATTERN,BECAUSELISTIMPLEMENTSBASICFUNCTIONALITY,ANDYOUPROVIDETHESTRATEGYINTHEFORMOFAFILENAMEFILTERINORDERTOCOMPLETETHEALGORITHMNECESSARYFORLISTTOPROVIDEITSSERVICEBECAUSELISTTAKESAFILENAMEFILTEROBJECTASITSARGUMENT,ITMEANSTHATYOUCANPASSANOBJECTOFANYCLASSTHATIMPLEMENTSFILENAMEFILTERTOCHOOSEEVENATRUNTIMEHOWTHELISTMETHODWILLBEHAVETHEPURPOSEOFACALLBACKISTOPROVIDEFLEXIBILITYINTHEBEHAVIOROFCODEDIRFILTERSHOWSTHATJUSTBECAUSEANINTERFACECONTAINSONLYASETOFMETHODS,YOURENOTRESTRICTEDTOWRITINGONLYTHOSEMETHODSYOUMUSTATLEASTPROVIDEDEFINITIONSFORALLTHEMETHODSINANINTERFACE,HOWEVERINTHISCASE,THEDIRFILTERCONSTRUCTORISALSOCREATEDTHEACCEPTMETHODMUSTACCEPTAFILEOBJECTREPRESENTINGTHEDIRECTORYTHATAPARTICULARFILEISFOUNDIN,ANDASTRINGCONTAININGTHENAMEOFTHATFILEYOUMIGHTCHOOSETOUSEORIGNOREEITHEROFTHESEARGUMENTS,BUTYOUWILLPROBABLYATLEASTUSETHEFILENAMEREMEMBERTHATTHELISTMETHODISCALLINGACCEPTFOREACHOFTHEFILENAMESINTHEDIRECTORYOBJECTTOSEEWHICHONESHOULDBEINCLUDEDTHISISINDICATEDBYTHEBOOLEANRESULTRETURNEDBYACCEPTTOMAKESURETHEELEMENTYOUREWORKINGWITHISONLYTHEFILENAMEANDCONTAINSNOPATHINFORMATION,ALLYOUHAVETODOISTAKETHESTRINGOBJECTANDCREATEAFILEOBJECTOUTOFIT,THENCALLGETNAME,WHICHSTRIPSAWAYALLTHEPATHINFORMATIONINAPLATFORMINDEPENDENTWAYTHENACCEPTUSESAREGULAREXPRESSIONMATCHEROBJECTTOSEEIFTHEREGULAREXPRESSIONREGEXMATCHESTHENAMEOFTHEFILEUSINGACCEPT,THELISTMETHODRETURNSANARRAYINPUTANDOUTPUTI/OLIBRARIESOFTENUSETHEABSTRACTIONOFASTREAM,WHICHREPRESENTSANYDATASOURCEORSINKASANOBJECTCAPABLEOFPRODUCINGORRECEIVINGPIECESOFDATATHESTREAMHIDESTHEDETAILSOFWHATHAPPENSTOTHEDATAINSIDETHEACTUALI/ODEVICETHEJAVALIBRARYCLASSESFORI/OAREDIVIDEDBYINPUTANDOUTPUT,ASYOUCANSEEBYLOOKINGATTHECLASSHIERARCHYINTHEJDKDOCUMENTATIONBYINHERITANCE,EVERYTHINGDERIVEDFROMTHEINPUTSTREAMORREADERCLASSESHAVEBASICMETHODSCALLEDREADFORREADINGASINGLEBYTEORARRAYOFBYTESLIKEWISE,EVERYTHINGDERIVEDFROMOUTPUTSTREAMORWRITERCLASSESHAVEBASICMETHODSCALLEDWRITEFORWRITINGASINGLEBYTEORARRAYOFBYTESHOWEVER,YOUWONTGENERALLYUSETHESEMETHODSTHEYEXISTSOTHATOTHERCLASSESCANUSETHEMTHESEOTHERCLASSESPROVIDEAMOREUSEFULINTERFAC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