Elements of imodeli into Java: i iklasi nje, i-interface

Ingcamango ephambili kwiklasi abstract iqulethwe kwezi ziphakamiso zilandelayo: maxa wambi kufuna akukho iiklasi zokupheka, yaye ifom "ezimanzi". okusilelayo ayide ikwazi nelokungasetyenziswa ngokuthe ngqo (instantiate).

Yintoni i class abstract kwi Java

Nanku omnye umzekelo. Kukho Java iklasi abstract Ikhalenda package Java.util. Oku akuthethi ukusebenzisa ikhalenda oluthile, nto leyo isetyenziswa, umzekelo, ngo-Koloni naseMpuma Yurophu, China, North Korea, Thailand njalo njalo D. Kodwa iimpawu ezininzi luncedo, njengokudibanisa kwiintsuku ezimbalwa ukuya kumhla ethile:. Le misebenzi kufuneka nasiphi na ikhalenda yozalisekiso. Akwenzeki ukuba kuvelisa ikopi kwiklasi abstract.

Iiklasi Abstract, iindlela Java abstract

Masithi ufuna ukuphuhlisa izinto ezininzi zomzobo, umz, iimilo zejiyometri: .. A isangqa, uxande, inkwenkwezi, njl Kwaye kukho kwisiphatho ubatsalela. Icandelo ngalinye Imbonakalo ezahlukeneyo, ngoko ke indlela efanelekileyo (nokuba ibizwa ngokuba ngepeyinti) kukho ukusebenza ngenye indlela. Nangona kunjalo, inxalenye nganye ezifanayo ezininzi: .. Lo mzobo kufuneka zifakwe kwibhokisi abe umbala ukuba nezisemhlabeni, ezinokubonwa nezingenakubonwa, njl Ngamanye amazwi, kufuneka udale i iklasi umzali zonke ezi manani, apho icandelo ngalinye ilifa iipropati jikelele. Kodwa kuthekani na indlela ipeyinti? Ngapha koko, udidi umzali akukho lumelo olubonakalayo. Xa uvuma indlela ipeyinti kwiklasi nganye ngokuzimeleyo, kuya kuba yimfuneko ukuba ukuhlalutya oko candelo kusetyenzwa, uze wenze maka. Ngoko ke, le ndlela kufuneka kuthiwe abstract kwi iklasi lomzali: indlela ezibekwe ngayo isihloko ngaphandle komzimba. A umzimba iklasi nganye asuka aya ukuchaza lakhe. E Java, i iklasi abstract ungakwazi ukungena iindlela abstract.

Ukuba iklasi ibe iindlela abstract, eklasini abstract. Phambi kweklasi ilizwi ukubeka elingundoqo abstract, isihloko indlela - kakhulu. Emva kokuba isihloko indlela enjalo kuyimfuneko ukuba semicolon. E Java, i udidi abstract akakwazi ukuvelisa iikopi. Ukuba sifuna ban indalo wabo, nokuba akukho iindlela nje eklasini, iklasi zingabhengezwa abstract. Kodwa ukuba iklasi uye indlela enye ubuncinane abstract, iklasi kufuneka abstract. Akwenzeki ukuba eklasini kwaye abstract kukuthi, neyokugqibela, kunye nendlela kakhulu. Le ndlela ayikwazi kuba abstract, zabucala, emile, lweenkobe. Ukuze subclass umntu avakalise non-abstract kwaye instantiate, kufuneka zisebenzise zonke iindlela nje umzali. Iklasi ngokwayo Ungasebenzisa iindlela zayo abstract.

umzekelo:

• class abstract AClass {
• zikarhulumente abstract indlela oswele (int a) ;
• }
• iklasi BClass akunika AClass {
• indlela kawonke void (int a) {
• // umzimba
• }

eziguquguqukayo Abavunyelweyo ezifana class abstract. Baya linokubhekisela umntwana non-nje ukuba iklasi okanye null.

Ujongano e Java - enye indlela ilifa ezininzi

E Java, akukho ilifa ezininzi, kuba ngoko kukho iingxaki ezithile. Iklasi akakwazi ilifa kwiiklasi ezininzi. Kodwa uyakwazi ukuphumeza kujongano ezininzi.

interfaces Java kunye neeklasi abstract - iingqiqo ezifanayo, kodwa hayi ncam. I-interface zingabhengezwa njengoko yoluntu, ngoko ke iyafumaneka kubo bonke, okanye ashiye uluntu sokuguqula kancinane, ngoko ke interface ifumaneka kuphela ngaphakathi package yayo. asifuneki elingundoqo Abstract, kuba interface kwaye unjalo abstract, kodwa ungakhankanya.

An isibhengezo interface

Iqala header, kwaye kuqala uye kuluntu elingundoqo, ngoko - interface lizwi. Ngoko kubekho ilizwi oluya kunye interfaces transfer, ilifa lo. Oku akuvumelekanga ukuphinda, kwaye akunakwenzeka ukuba benze umlinganiselo elibujikele ubudlelwane ilifa. Kwandule ke ukubakho umzimba interface, abhijelwe braces olugobileyo. Xa umzimba lojongano izinto wathi: constants Field kunye neendlela abstract. Zonke amasimi static kawonke lokugqibela - zonke ezi eyiyo yebug kwaye akukho mfuneko. zithathwa Zonke iindlela ukuba abstract kawonke - ezi modifiers nabo lingakhankanywa. Ngoku, kwanele Kuthiwa ngomahluko phakathi kwiklasi nje ukusuka Java interface.

• interface kawonke AI liphela B, C, D {
• // umzimba
• }

Ukuyixela iklasi ujongano indlalifa, kufuneka usebenzise izixhobo elingundoqo:

• iklasi AClass iyasebenza BI, CI, di {}

Oko kukuthi, ukuba emva kokuba isibhengezo yeklasi liphumeza igama interface ezicacisiweyo, izixhobo zawo eklasini. Ziindlalifa zalo iklasi iba sezulu, ngoko ke uyithengise.

Eziguquguqukayo luhlobo ujongano uvumelekile. Banako ukuba libhekisela uhlobo iklasi ukuba liphumeza le interface, okanye null. eziguquguqukayo ezifana zonke iziqalelo kodidi lwento, kuba izinto uzikise iiklasi, yaye, bona, usukele kodidi lwento.

Kweli nqaku, siye saxubusha ezinye iimpawu imodeli into Java - kwiiklasi abstract, abstract interface iindlela.