ICMP性能监控系统设计Word文件下载.docx

ICMP性能监控系统设计Word文件下载.docx

《ICMP性能监控系统设计Word文件下载.docx》由会员分享，可在线阅读，更多相关《ICMP性能监控系统设计Word文件下载.docx（75页珍藏版）》请在冰点文库上搜索。

Operatingonmultipleplatformsinheterogeneousnetworksinvalidatesthetraditionalschemesofbinarydistribution,release,upgrade,patch,andsoon.Tosurviveinthisjungle,Javamustbearchitectureneutral,portable,anddynamicallyadaptable.

TheJavasystemthatemergedtomeettheseneedsissimple,soitcanbeeasilyprogrammedbymostdevelopers;

familiar,sothatcurrentdeveloperscaneasilylearnJava;

objectoriented,totakeadvantageofmodernsoftwaredevelopmentmethodologiesandtofitintodistributedclient-serverapplications;

multithreaded,forhighperformanceinapplicationsthatneedtoperformmultipleconcurrentactivities,suchasmultimedia;

andinterpreted,formaximumportabilityanddynamiccapabilities.

DevelopingyourapplicationsusingJavaresultsinsoftwarethatisportableacrossmultiplemachinearchitectures,operatingsystems,andgraphicaluserinterfaces,secure,andhighperformance,WithJava,yourjobasasoftwaredeveloperismucheasier—youfocusyourfullattentionontheendgoalofshippinginnovativeproductsontime,basedonthesolidfoundationofJava.Thebetterwaytodevelopsoftwareishere,now,broughttoyoubytheJavalanguageplatform.

Javahasexactlytheoppositeproperty:

itforcesyoutomakeexplicitchoices.Alongwiththesechoicescomealotofassistance—youcanwritemethodinvocationsand,ifyougetsomethingwrong,yougettoldaboutitatcompiletime.Youdon’thavetoworryaboutmethodinvocationerror.

TheJavabeginnermustgrasp30basicconcepts

Basicconcept:

1.InOOPtheonlyrelationsiswhattheobject’sinterface,suchasthecomputersellerheleavesaloneinternalstructureofelectricalsource,butheisonlyconcernedaboutthatwhetherthepowerwillbesuppliedtoyou,alsosolongasknowcanornotbutisnothowandwhy.Allproceduresaremakeupofcertainattributeandthebehaviorobject,thedifferentobjectvisitinvokesthroughthefunctioninvocation,betweentheobjectallintercommunionareinvokethroughthemethodinvocation,Byobjectdataencapsulation,enhancesreuserateverymuch.

2.InOOPthemostimportantthoughtisclass,theclassisthetemplate,isablueprint,constructanobjectfromaclass,namelyconstructaninstanceoftheclass.

3.Encapsulation:

isthatcombinesthedataandthebehaviorinapackage）andhidesthedatatherealizationprocesstotheobjectuser,inanobjectdataiscalleditsinstancefield.

4.Throughexpandsaclasstoobtainanewclassiscalledinheritance,butallclassesareconstructedbytheobjectsuperrootclassofexpansion.

5.Object3principalcharacteristics

Behavior---explainedthisobjectcanmakewhat.

Tate---whentheobjectexertsthemethodobjectreflection.

Dentity---andothersimilarbehaviorobjectsdiscriminationsymbols.

Eachobjecthasonlyindentityandamongthreecharacteristicstheyaffectmutually.

6.Relationsamongclasses:

Use-a:

Dependentrelation

Has-a:

Polymerizationrelation

Is-a:

inheritorrelation--example:

AclasshasinheritedBclass,thistimeAclassnotonlyhasBclassofmethod,butalsohasitsownmethod（Individualityexistsingeneralcharacter）

7.Structureobjectusestructure:

Structureproposing,thestructureisonespecialmethod,thestructureobjectandtoitsinitialization.

8.Overloading:

Whenmanymethodshavethesamenamewhenincludesthedifferentparameter,thenhastheoverloadingWhichmethoddoesthecompilerhavetochooseinvokes.

9.Package:

Javaallowoneormanyclassestobecometogetherasgroup,iscalledpackage,toorganizingdutyeasily,thestandardJavastorehousedividesintomanypackagesJava.Langjava.Utiljava,netandsoon,thepackageislayeredandalljavapackagesareinjavaandinajavaxpackage.

10.Extendablethought:

permittoconstructnewclassonexistingclasses,whenyouextendtheclasswhichalreadyexisted,thenyoureusethisclassofmethodandthefield,atthesametimeyoumightaddthenewmethodandthefieldinthenewclass.

11.Expandableclass:

Theexpandableclassfullymanifestedis-atoextendtherelationsTheformis:

Class（subclass）extends（baseclass）.

12.Multi-modality:

Injava,theobjectvariableismulti-modalityButinjavadoesnotsupportmultipleextend.

13.Dynamiccombine:

themechanismofinvokingobjectmethodmechanism.

1）compilerexaminesobjectstatementtypeandmethodname.

2）thecompilerexaminesthatmethodinvokesparametertype.

3）staticcombine:

Ifthemethodtypeispriavtestaticthefinal,compilercanaccuratelyknowwhichmethodshouldinvoke.

4）whentheprocedurerunsandusesdynamiccombinetoinvokeamethod,themethodeditionwhichthenhypothesizedmachinemustinvokextheobjectactualtypewhichaimsattomatch.

5）dynamiccombine:

isaveryimportantcharacteristic,itcancausetheproceduretochangeagainmayexpandbutdoesnotneedtotranslatehassavedthecode.

14.Finalclass:

Inordertopreventotherpeoplederivethenewclassfromyoursclass,thisclassiscannotexpanded.

15.Thedynamicinvocationspendlongertimethanthestaticinvocationexpenditure.

16.Abstractclass:

Stipulatedormanyabstractmethodsclassofitselfmustdefineisabstract.

17.InJavaeachclassisbeextendedbyobjectclass.

18.equalandtoStringmethodinobjectclass.

Equalusesintestinganobjectiswhetherequalwithanotherobject.

ToStringreturnstorepresentthisobjectthestringofcharacter,eachclasscannearlyoverloadingthismethod,inordertoreturnstothecurrentconditionthecorrectexpression.（ThetoStringmethodisaveryimportantmethod）

19.Generalprogramming:

Anyclassoftypeallvaluesallmayreplacewithaobjectclassofvariable.

20.Thearraytabulates:

TheArrayListdynamicarraytabulates,isaclassofstorehouse,definesinjava.Inuitlpackage,butautomaticcontrolarraysize.

21.inclassandclassofobject,getclassmethodreturnstotheclasstypeanexample,whentheprocedurestartcontainscanincreaseinthemainmethodclass,hypothesizedconfidentialincreaseallclasseswhichheneeds,eachincreaseclassallmustincreasetheclasswhichitneeds.

22.Theclass:

classmightdynamicoperatethejavacodeforthecompilationtheproceduretoprovidetheformidablefunctionreflection,thisfunctionwasJavaBeansisspeciallyuseful,theusereflectedJavatobeabletosupporttheVBprogrammertobefamiliarwiththeusethetool.

23.interface:

shouldshowingclasscoulddowhatbutnottoassignhowtodo,aclassmayrealizeoneormanyinterfaces.

24.Theinterfaceisnotaclass,butistoconformstoainterfacerequestclassofsetofstandard.

25.Aclassonlythenasuperclass,butaclasscanrealizemanyinterfaces.InaJavaimportantinterface:

Cloneable.

26.Theinterfaceandcall-back:

toprogramsacommonlyusedpatterniscall-back,inthepattern,youmayreferwhenthisclassofpatternsettledspecifictimeoccursreturnstoadjustsontheobjectthemethod.

27.Objectclone:

Theclonemethodisaobjectprotectionmethod,thismeantyourcodecannotsimpleinvokeit.

28.Innerclassaninnerclassdefinitionisthedefinitioninanotherclass.

Thereasonis:

1）aninnerclassobjectcanvisitfoundsitsobjectrealization,includingprivatedata.

2）aboutotherclassesinthesamepackageinthat,innerclasscanbehided.

3）theanonymousinnerclassmaytheveryconvenientdefinitionaccent.

4）usesthecategorytobepossibletheextremelyconvenientcompilationeventdriver.

29.Agentclass（proxy）:

1）appointingallcodesthatinterfacesrequest

2）allmethods（toStringequals）thatobjectclassdefine

30.Datatype:

Javaiskindofemphasizingtypelanguage,eachvariableallmustbedeclareditstypesatfirst,injavaaltogetherhas8basictypes.fourkindsarethelong,twokindsarethefloat,oneisthechar,beingusedintheUnicodecodechar,Boolean.

1.javaissimple

JavaandC++areverysimilar,butmuchsimpler.Allthehigh-levelprogramminglanguagefeatures,isnotabsolutelynecessaryhavebeendeleted.

2.Javaisobject-oriented

Javaisanobject-orientedprogramminglanguage.Inadditiontothesimpletypes,suchasdigitalandBooleanoperatorsinaddition,Javaisanobjectofmost.Aswithanyobject-orientedlanguages,Javacodealsoorganizedbycategory.Eachcategoryprovidesadefinitionoftheobjectbehavior.Anothertypeofsuccessioncanbeakindofbehavior.Inthecategoryoftherootlevel,oftenthetargetcategory.Javasupportforthesingletypeofinheritedhierarchy.Thismeansthateachcategorycanonlyinheritoneother