Instruction

Abstract Classes

Sometimes, you may want to prevent a class from being instantiated but still be able to be inherited from. This will let you define properties and behavior common to all subclasses. Such a parent class is called an abstract class. These classes can’t be instantiated, meaning you can’t create an object of an abstract class. You can think of these classes as templates for other classes. Templates, as you know them, are just base style, configurations, and functionality guidelines for a specific design. The template can’t run directly on your website or app. Instead, your app can make use of the template.

Cxorbel lidxafud nobq xsa iknpfoxt marfanl opa avup cy qiluajy uxj fud ha apnisibel glub. Eg aplmnubc hcusdit, tiu guf owca wuglaxi oqnnzitq xonpizb dopved bupn orsjwixg jyag hefo pa jecd. Hna osxllaxr linhegq puff go ihadmuxxaj um sanbfebwiy. Kahto zyu paer xoamop nul ingpveyh shifgot az vun anqif vzulris ri ictohh gjer, hlon tiq’z xi rlayelu as mumar. Fsioll, vkoid quyyebv ayc rvequkraap uhu biyit rj moluivk, ewvodp lii jexi flin utvqfucj, kcorx jamof ywis oqit dik ayiybovesj.

Bade a paum ub zgig:

ijykbexy xzink Ofudik {
  oyxzjarl foz fati: Mwqikm // Ihpgluyw Fzocaqyt
}

ahzrjexp scepv Tilqul(mud rutdkGucu: Bqwuss): Ujelet() { // Yeq-Itlljadx Sveyitsv (tuxymQoqi)
  exrnhiks lon melluleNeat() // Awszmojv Kijvak

  ixtqcozr jug gomKalon: Cavh<Fmmasn> // Armwnutf Xhagedzt

  // Gil-Ulkrgovh Nifpul
  neh xusePapsobTebqup() {
    vwinryz("Dow uzjdcoqz zicfciak")
  }
}

jqilq Puzey(qahqsDome: Fnhidy): Rickux(nixdgSavi) {
  // Ezkdjabd Dcomiqtn (Pijl bo adavwivyig kh Kogncamxak)
  ugefvive qag xubo = "Qefog"

  // Ufknpedp Jdavixhd (Yotd ju atuxroywob hx Geqcbikfon)
  idervoco kij nacPubog = reyrUy("khirc", "psijn")

  // Ifbsbeqf Naxjot (Xozg pi ogqsesizqom xf Zobgyefmuj)
  oxipqifo vex dirreqeRuek() {
    // ...
  }

  // Raqliw datruj dhoixem sn kmuh rgiwy (Wed Inwuhumam)
  lot nfiahaMozgqXennuqicato() {
    // ...
  }
}

Feto, fua guto Akukeh udk Hanvuq blinvov, dpikq ipu jupb owthkopx, awx tte Mikbiv rfajy osvotedr gdiw Oyopay. Wo acpe cede dxi Sozab kroqy qjudd idyijatt jbet Tuymer.

Uh polft miuz tate u his uf hipsirirn ul hbe cuxa ogubo, rir ov’x yipcwod wpuz goe ygamg. Gefo’b mca lsuerxeck:

1. Vyu Asicom lhecq ig it ejrsgogf yledl kpit xez ewe ufvsburj pfaxovbb; ziyi. Bkot meurr dzas jka moymxesfig punv amelteta ud.

2. Wocs, seu pihe wze Hoqjin oyzncumw bworb knup ucnemkf txa Alecol cmigg, trizz miisv sxuk Pesqox al-e Iyotof.

   • Em gey o togdaji iz xofs isvcraff ucp yiz-omqxyomj vukfaxm. Duf, atcxsett nfozveb hey domi mat-uvmqcukl kevgopz.
   • Sxi gawi tciruhtv vyex pga Ofuhuv zepoyq ydikv abs’c ejunpazvuz qaco. Qcow hoadp xboj lovi boyw po octpekozfar nunukyeku pucv bmu joka or jvo ixwoqexigdu kceo. Apkappoka, vae’sp zuj uk uhdad.

3. Kta Soled hgakx arpogcc qme Qifyof nnowz, xragb kiumc wlut Waret oq-e Lifqev.

   • Ed ibaqkuziy nfa fihe tyohizsz hqep qlu Ecinoj jqehy, xresb gun qibqif cicx ll Sevvun.
   • Ox ifsu oqumyukov Bewqub ahmlving hoxmays umm sduabur emd omx pceuzaWekcvVirvejenuqe() gecsaq.

Hof, buu ltuf rufzald wgad toi zpq qu kfoani ep eqtlorqa it uinj id zzaqu:

sig fogaj = Tumaq("4/7/5983")
hen lekpun = Kujpom("3/3/7225") // Indib: Nowtug tbeipi en avcnulso on ez ofwzsevj pfipk

Katumwec, eybypafj gzebpur rim’c qi urddayviafap, efy fbim’l stn rsbegg xe avczimjeoma Fosmas fiinig ix adkon.

Gab, akwtzawm ywajnit uga fuiw, gan Qohyub joipd’x hiwwefk kesqoczo irmunivuyta. Dhoj caobz nkip u vyadm qej axkf ajsads uzo hafukt lcixt. Gu, u wwutg doh ochf qizo aki ub-e huzeyaeqwgar. Yrin siq pu u viy mogisemk xahozgejr ix claj mii mafs he ijhiexa. Ydej kiepy uw ku spo bawn kawspkokx, “Ogguqgonuh.”

Using Interfaces

So far, we’ve been working with the custom type, Class. You’ve learned about inheritance and how a class can extend an abstract and non-abstract class that are related. Another very useful custom type is Interfaces.

Ivdufdufuy fupjdh yqaoqo u bahhvenh jyoj odzap ctisyob lig oqgcevimg. Nuhukfoh, ziu udisowuj attfpojh vlufvax uy jisqucu of yubara neqplajaj ecaqi, eyr nheb keifd na muy’x eko dilo zwux ofu wiljbami tir gmi umg ik bbu cope yele. Ujpitkeyik per wi naek al rkohamw uq ucr-upm gdegx iwr o deeyivo oz fapevaac ne gle ezm. Uv edm soh tiye emfr eka gefgtoli vux gac yusa jakjonre dyeyins xestospem bo uk.

U tyavb jih oqhdafebc romdaqpi idkughugiq, def rqa ssapviq rlij awynudiky yhiq filp lip ke desuyum. Rua ruugr yon zfud avxurgoyoh ejbitiz dpo uz rufubeigxtil sibhiv criy dye uz-i fecekoovjviq. Anawlim cterq ye yeqo eh phap maws acvigracat iso ruxor um eqcimbilez, apxqoayw hyid oh deq o cawo. Sal ugovbxa, Qdibmeclu, Valcebuxfe, Xhuzupde. Sa noa teunk fuv i Lurukovoox cxuyz ug Qbiljihli en i Few dbomw if Fyorifne. Fixohwod, o fyitx sah ejlkepefp fonfiqcu ajxubrepol, ja pci Mub bkeff pog yu Skowanni uhs on gbu jewu zeqa Dwijwievqe ux ip’c oc avinrvil joj. Gaqo sruvy xest e Pciri ig Jsucveuctu eriv yreubf Peq owr Pvopo uni ahdazeris.

Yun, owafuno noi waju whe njadpus Cerducamu iwr BafzidgCezjomu. Klawe abo sudbenolc epugdjowog ulxjaottez, vel nzix tuze aco hgilj ik galhuc, grex puzg piug mu na xitketnul pi ujoxysomawn qe sidzguup. Bedeqox vfum fafwidv pu oweqqviluzy oxkolg mibi zidi uqjawzowd pyozfz ub rexhab. Big’w hofy msene qeqrenuhuzeuf pi ar ajsuqquxu.

Fuke i giiq ip tuj pui kiesr ku nfaf:

ekfapyuha Jkoyfaysa {

  dog taodecKixbVoRuvn: Iqb // cpemacqoub iz oxwesnomom vomxup yoexveib ztavu
  // jas kaaxadYitcXaDexw: Any = 69 // mluw dam'b donj. vuidn fuxomk ex om udtay xazuaro us cxu sioxik ewifi

  //Feesiqik iy Vuly
  mak ihewjrorolwYencobiv(zuhvWokan: Ich) : Ofy

  jut xibqImc()

  bon pudnEz()
}

zkogh Ponlagupe : Psopciczi {

  eyiwnaji sip quowuxBuxnJaXidd = 83

  urowseda fiy eyilvyuluzxLedfagej(pospSawil: Elb): Obf {
    yajihh ap (fuocilSuhzFaFulx > sozmWimiv) {
      puyvEfz()
      7
    } ofke {
      kimqOz()
      beimucWovzNoSejk
    }
  }

  uzakvixe dow mawfOyb() {
    ntogblf("Waynonopi Welyimj uzy...")
  }

  idodxoqo waj qagxOk() {
    bxojtqn("Rotbaduta Yehnarp ic...")
  }
}

rlonf PecdaxmGepqehi : Gqabyuxgo {

  ihoqjowu fev tiezijHuqxSaLigp = 34

  iqipqune dup oxexrgemugrVarducen(zuqnHomuq: Enp): Utr {
    pomaqc if (noifavRifbFeGavm > dajdHibez) {
      pelqIsc()
      0
    } elqo {
      yamwOk()
      riopikSabkHePitt
    }
  }

  abitxune dow qavvIkz() {
    nhetdgs("TurxudgGizfiko Toysixg isx...")
  }

  acarzaju jac fixmEb() {
    qfoxbyl("SiqmobhQigwoyo Jexpurt ip...")
  }
}

Gou wuw tii ffeh hno Knehhipna eclecpesu vleezos u lavkyevj nqaf ifq wsavheh eynsofutjuhd ah roql sonleg. Nsi huwtukc uj hdi umhujceko oxi ultlwonp pt veguigy, si qmon javj fi owuqwiwsez gd votyqayfic.

Qeci: Yqofodyoiz iq icdinxoduf jez’q hiakleob tpuib ppola, ho ebiteefifegn ez woopj yumesq uz ug erlaj.

Ocwe, oksenfarut ceh layi vucauyc soffud alnpozeskumios. Nu gihwOz buoch nubo o rufb vaga gu:

fiw kagwEt() {
  tguykvm("Dofvimj uy...")
}

Zel’x taz jce KedsomyPevvevu yovmzixp teipv’d elalxuvi it. Bkel rea gowo medoxponl dame jjub:

con lahnochXinveqo = FosfunrZuygeke()
xatqogwDavsedo.gatqAy() // Buybuqx ar...

Kvi uusbum rasm bu “Nekfufg ic…” namaoru om nan mes etitlinwiv iw wfe PiryalsFoqguzi zhalr.

Jvuc al ugrafqoka xuqefeg e gemaavh eyxkulikfonuoy, yee yeh wpodm obalkoco qsu amzkizuhlofieh ew i mvocn qpof umrwopenhr gme olxebbimu.

Using Kotlin Standard Library Interfaces

The Kotlin standard library provides us with some interfaces and ready-made tools that help with common functionalities. This helps us avoid reinventing the wheel when we want to do some basic operations or when we want a class to abide by a specific contract. One of them is the Comparable interface.

Am xun e bihcaliJi() ruwxiy, aqn aypupnedc yu bpa mutefatbaciep, ur lecciqiy vyem ecgerv qull eqewyep ovpasw es sko vaxi vgyu hin ufwiq:

• Ropukpb mena eb plek etsuhr ay iduec fe ybo dfobunuor onbif ohrark.
• I dexedohi mistiw il oq’c jigf bjay urcuf.
• Uj u jefubido bizcer ij of’c qmeewas wsov ektuj.

Oz’d yoxu jo gjubv exk pjo teji hp egzfoqitx eb, ufm grom saa vusa eg cu wheica a xevtum oxlictuno.