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1、Mobileapplicationplatform-J2MEprofile1.whatistheJ2MEJ2ME(Java2MicroEdition)isaJava2asanintegralpartofitwithJ2SE,J2EEsaid.AccordingtoSun'sdefinition:J2MEisahighlyoptimizedJavaruntimeenvironment,mainlyforconsumerelectronicsdevicessuchascellularphonesandvideophones,digi
2、talset-topboxes,carnavigationsystemsandsoon.J2MEtechnologyin1999,theJavaOneDeveloperConferenceontheformallaunchoftheGeneralAssembly,whichwilloftheJavalanguageandplatform-independentfeaturesintoasmallelectronicdevicethatallowsmobilewirelessdevicessharingbetweenapplica
3、tions.J2MEinitsdesignspecifications,tofollowa"varietyofdevicestocreateasingledevelopmentsystemismeaningless"thebasicprinciples.SofirstofallJ2MEembeddeddevicesgenerallydividedintotwotypes:Oneisthelimitedcomputing,powersupplyisalsolimitedembeddeddevices(forexample,PDA,
4、cellphone);anotherkindofcomputingpowerisrelativelybetter,Andinthepowersupplyisrelativelysufficientforembeddeddevices(forexample,airconditioners,refrigerators,TVset-topboxes(set-topbox)).Becausethesetwotypesofembeddeddevices,JavaiswhytheintroductionofaconceptcalledCon
5、figuration,andthentheoperationoftheabovefeaturesarelimited,limitedthepowerofthedeviceembeddedinthedefinitionofConnectedLimitedDeviceConfiguration(CLDC)specificationsare;andtheotheroneTostandardizethetypesofdevicesareConnectedDeviceConfiguration(CDC)specifications.Ino
6、therwords,J2MEfirstofallembeddeddevicesusingtheConfigurationconceptofseparateintotwokindsofabstractpatterns.Infact,everyoneherecanbeaConfigurationforJ2MEtwotypesofspecificationsforembeddeddevices,whichdefinesthespecificationsofthesedevicesatleastinlinewiththecomputin
7、gpowerandcapacityofpowersupply,memory,andothernormsSize,aswellassetAsetofthesedevicesontheimplementationoftheJavaprogramcanbeusedbythetypeoflibrary,thesenormsaredefinedbythetypeoflibraryfortheJavastandardlibrary'scorecategoriesandsub-typedevicefeaturesthelineTheexpan
8、sionofthelibrarycategory.Forexample,onCLDCspecifications,cansupportthecorecategoryforthelibraryjava.lang.*,java.io.*,java.util.*,an
