Nnianimu
Wɔ ahemman a ɛfa nneɛma ho nhyehyɛe mu no, ntease a wɔbɛte ase wɔ akwan a wɔfa so nya nneɛma no ho no ho hia kɛse ma mmara a ɛyɛ den na wotumi hwɛ so yiye a wɔbɛhyehyɛ. Nsusuwii ahorow a ɛfa ahobammɔ ne kokoam akwan a wɔfa so nya nneɛma ho no di dwuma titiriw wɔ encapsulation mu, nnyinasosɛm titiriw a ɛhwɛ ma ade bi tebea yɛ pɛ. Wɔn a wɔyɛ no taa di aperepere wɔ saa nsakrae abien yi mu a wɔbɛpaw de akari pɛ wɔ akwan a wɔfa so kɔ hɔ ne ahobammɔ mu wɔ wɔn aplikeshɔn no mu. Saa asɛm yi hwehwɛ n’ankasa asɔremma a wɔabɔ wɔn ho ban no mu nsɛm nketenkete mu kɔ akyiri, na ɛhwehwɛ nea ɛkyerɛ wɔ nhyehyɛe kasa ahorow mu.
Nteaseɛ a ɛfa kwan a wɔfa so nya kwan .
Access modifiers yɛ keywords a wɔde di dwuma wɔ object-oriented languages mu de hyɛ accessibility a ɛwɔ classes, methods, ne variables mu. Wɔkyerɛkyerɛ sɛnea wobetumi anya adesuakuw bi mufo wɔ dwumadi no afã afoforo mu. Primary access modifiers no bi ne public , protected , private , ne ɛtɔ da bi a default anaa emu , a egyina kasa no so.
Ɔmanfo kwan a wɔfa so kɔ hɔ no mu nsakrae .
Asɔremma a wɔakyerɛ sɛ wɔyɛ ɔmanfo no yɛ nea wobetumi anya afi adesuakuw foforo biara mu. Saa kwan a wɔfa so nya nneɛma yi ma kwan ma wonya kwan a ɛtrɛw sen biara a wobetumi anya nanso ebetumi ama nkitahodi a wɔanhyɛ da na wɔatew so.
Private Access Modifier .
no Private access modifier siw adesuakuw no mufo a wotumi hu wɔn no ano wɔ adesuakuw a wɔde wɔn ho to so no mu. Eyi hwɛ hu sɛ encapsulation a ɛkorɔn, a ɛmma abɔnten adesuakuw no ntumi nkɔ saa asɔremma yi so tẽẽ anaasɛ wɔnyɛ nsakrae.
Ahobanbɔ a Wɔde Kɔ Access Modifier .
Asɔremma a wɔwɔ modifier a wɔabɔ ho ban no yɛ nea wotumi nya wɔ wɔn ankasa adesuakuw mu ne adesua a wonya fi mu. Saa access level yi kari pɛ wɔ private ne public ntam , ɛma subclasses no tumi de di dwuma na ɛtrɛw adwumayɛ mu bere a ɛkura encapsulation bi mu.
Private vs. wɔabɔ ho ban: nsonsonoe atitiriw .
Nsonsonoe titiriw a ɛda private ne protected access modifiers ntam no gyina accessibility level a wɔde ma subclasses ne external classes no so.
Nneɛma a wotumi nya wɔ subclasses mu .
Ankorankoro asɔremma no ntumi nkɔ subclasses mu, sɛ mpo subclass no wɔ package anaa module koro no ara mu a. Wei kyerε sε akwan anaa variables a w’apae mu aka sε private no ntumi nnya agyapadeε anaa wכn de di dwuma tẽẽ wכ adesua ahodo mu. Nea ɛne eyi bɔ abira no, wotumi nya wɔn ankasa asɔremma a wɔabɔ wɔn ho ban no wɔ akuw nketewa mu, na ɛma wonya agyapade ne polymorphism ma ɛyɛ adwuma yiye.
Encapsulation ne ahobammɔ .
a wɔde di dwuma Ankorankoro asɔremma no ma encapsulation nya nkɔso denam dwumadie ho nsɛm a wɔde sie a ɛfiri adesuakuo afoforɔ nyinaa mu no so. Eyi betumi asiw ntwitwiridii a wɔanhyɛ da ayɛ ano nanso ebetumi asiw ntrɛwmu ano. Ɔkwan foforo so no, asɔremma a wɔabɔ wɔn ho ban no da nsɛm bi adi kyerɛ akuw nketewa, na ɛma ntrɛwmu no yɛ mmerɛw nanso ebetumi akɔ asiane mu sɛ wɔanhwɛ so yiye a.
Nneɛma a wɔde di dwuma a mfaso wɔ so .
Sɛ wopaw nea wɔabɔ ho ban ne nea ɛyɛ kokoam a, egyina softwea a wɔreyɛ no ahwehwɛde pɔtee so.
Bere a ɛsɛ sɛ wode private di dwuma .
Fa di dwuma private bere a wopɛ sɛ wohyɛ encapsulation a ɛyɛ katee no mu den. Eyi fata ma akwan a wɔfa so de di dwuma anaasɛ nsakrae a ɛnsɛ sɛ wɔsesa anaasɛ ɛkɔ adesua no akyi. Ɛbɔ tebea a ɛwɔ mu no ho ban na ɛhwɛ hu sɛ nsakrae a ɛba adesuakuw no mu no nnya abɔnten adesua so nkɛntɛnso.
Bere a ɛsɛ sɛ wɔde ahobammɔ di dwuma .
Paw ankasa asɔremma a wɔabɔ wɔn ho ban bere a wɔreyɛ adesuakuw bi a wɔahyɛ da ayɛ ama agyapade ho nhyehyɛe no. Wei ma subclasses no nya kwan kɔ na wɔsesa saa asɔremma yi, hyɛ code reuse ne extension ho nkuran. Ɛho hia wɔ nhyehyɛe ne nhomakorabea ahorow mu baabi a extensibility yɛ ade titiriw a ɛhaw adwene.
Nhwɛso ahorow a ɛwɔ programming kasa ahorow mu .
Sɛnea kasa ahorow de saa akwan a wɔfa so nya nneɛma yi di dwuma no ho ntease ho hia kɛse ma kasa ahorow a wɔde di dwuma wɔ aman ahorow so ne sɛnea wɔde tumi a ɛwɔ nhyehyɛe a ɛfa nneɛma ho no nyinaa bedi dwuma.
Java .
Wɔ Java mu no, ahobanbɔ kwan a wɔfa so nya kwan no ma wotumi hu ade wɔ package koro no ara mu ne subclasses mpo sɛ ɛwɔ package ahorow mu a. Private . modifier no siw kwan a ɛkɔ declaring class no nkutoo so Nhwɛsoɔ bi nie:
public class parent {
protected void display() {
// protected method
}
}
public class abofra no trɛw ɔwofo {
ɔmanfo void kyerɛ() {
display(); // ɛyɛ mmerɛw sɛ wobenya
}
} .
C++ .
C++ di nhwɛsoɔ a ɛte saa ara akyi, nanso wɔde ka ho sɛ wɔbɛkyerɛ agyapadeɛ a wɔde kɔ mu levels. Asomfo a wɔabɔ wɔn ho ban no yɛ nea wotumi nya wɔ adesuakuw a wonya fi mu mu, bere a ankorankoro a wɔyɛ asɔremma no nyɛ saa.
class base {
wɔabɔ ho ban:
int protectedvar;
Kokoam:
int privavar;
};
Class derived : ɔmanfo nnyinaso {
void function() {
protectedvar = 1; //
privatevar = 1 a wotumi nya bi; // ɛnyɛ nea wotumi nya
}
};
Nea ɛkyerɛ ma software nhyehyɛe .
Paw a wopaw wɔ ahobammɔ ne kokoam ntam no nya wo mmara no mu nsakrae ne ahobammɔ so nkɛntɛnso.
Extensibility .
a wode bedi dwuma Wo ankasa asɔremma a wɔabɔ wɔn ho ban no ma w’adesua ahorow no trɛw kɔ soro. Subclasses betumi anya agyapade na leverage saa asɔremma yi de asi dwumadie a ɛwɔ hɔ dada no so a wɔrensesa base class no.
Nsiesie
Adesuakuw no mu nneɛma a wɔde abɔ ho ban a ɛda adi boro so no betumi de nsɛnnennen a ɛfa nsiesie ho aba. Nsakraeɛ a ɛba wɔ base class no mu no bɛtumi anya subclasses so nkɛntɛnsoɔ wɔ akwan a wɔanhwɛ kwan so, ama codebase no ayɛ den sɛ wɔbɛhwɛ so.
Nneyɛe a eye sen biara .
Nneyɛe pa a wobɛbata ho no hwɛ hu sɛ wo de access modifiers di dwuma no ma wo code no yɛ kɛse sen sɛ ɛbɛsiw ano.
Favor composition wɔ agyapade so .
Sɛ wɔde wɔn ho to asɔremma a wɔabɔ wɔn ho ban so dodo a , ebetumi akyerɛ sɛ wɔwɔ agyapade a ɛboro so. Susuw ho sɛ wode composition bedi dwuma na ama woanya code reuse, a mpɛn pii no ɛde code a ɛyɛ mmerɛw na wotumi hwɛ so ba.
Minimal hia a ɛho hia .
Ma kwan a ɛba fam koraa a ɛfa kwan a wɔfa so nya no ho. Sɛ ɛho nhia sɛ ɔmannifo bi nya bi wɔ subclasses mu a, ma ɛnyɛ private . Saa adeyɛ yi ma tumi a ɛwɔ hɔ sɛ wobenya ɔhaw ahorow a wɔanhyɛ da ayɛ no so tew.
Nsɛm a wɔayɛ ho nhwehwɛmu .
Wiase ankasa mu nsɛm a ɛfa baabi a akwan a wɔfa so yɛ nsakrae a wɔpaw no nyaa nkɛntɛnso kɛse no betumi ama wɔanya nhumu a ɛsom bo.
Open-source nhyehyɛe ahorow .
Frameworks pii da wɔn ankasa asɔremma a wɔabɔ wɔn ho ban adi ma developers kwan ma wɔtrɛw base classes mu. Sɛ nhwɛso no, wɔ wɛb frameworks mu no, base controller classes taa wɔ akwan a wɔabɔ ho ban a wobetumi ayɛ so de ayɛ suban a ɛfata.
Ahobammɔ ho mmara a wobu so esiane sɛ wɔda no adi boro so nti .
Nsɛm bi asi a wɔde akwan a wɔabɔ ho ban a wɔde di dwuma ɔkwammɔne so no maa ahobammɔ ho mmerɛwyɛ bae. Subclasses no nyaa base class internals no mu na wɔsesaa no wɔ akwan a wɔanhyɛ da so, na ɛde instability ne breaches bae.
Nkɛntɛnso a kasa mu nneɛma nya .
Kasa mu nneɛma pɔtee bi betumi anya sɛnea access modifiers yɛ wɔn ade no so nkɛntɛnso na ɛsɛ sɛ wosusuw ho bere a wɔreyɛ software ho nhyehyɛe no.
Adamfo adesua wɔ C++ mu .
C++ de ho adwene ba adamfo adesua ne dwumadie , a ɛtumi nya private ne protected class no mufoɔ. Saa ade yi de nsɛm a ɛyɛ den ka ho ma wotumi di so na ɛsɛ sɛ wɔde di dwuma wɔ ɔkwan a ɛfata so.
Adwendwene wɔ Java ne C# mu.
Kasa ahorow te sɛ Java ne C# ma kwan ma wosusuw nneɛma ho, a ebetumi anya private members wɔ runtime mu. Bere a tumi wom no, saa tumi yi betumi asɛe akwan a wɔfa so kɔ hɔ no na ɛsɛ sɛ wɔde ahwɛyiye di ho dwuma.
Sɔhwɛ ne akwan a wɔfa so nya nneɛma .
Access modifiers betumi aka tumi a wɔde sɔ code hwɛ yiye.
Ankorankoro asɔremma a wɔresɔ ahwɛ .
Wɔtaa bu ankorankoro asɔremma a wɔbɛsɔ wɔn ahwɛ tẽẽ no abam. Mmom no, ɛsɛ sɛ sɔhwɛ ahorow no twe adwene si ɔmanfo ntam nkitahodi so. Nanso, ɛtɔ mmere bi a eyi betumi ama ayɛ den sɛ wobenya mmara a edi mũ.
Asɔremma a wɔabɔ wɔn ho ban wɔ sɔhwɛ mu .
Ankasa asɔremma a wɔabɔ wɔn ho ban a wɔde bedi dwuma no betumi ama sɔhwɛ ayɛ mmerɛw denam sɔhwɛ akuw nketewa a wɔbɛma kwan ma wɔanya na wɔayɛ nsakrae wɔ base class suban mu no so. Saa kwan yi betumi ayɛ nea mfaso wɔ so nanso ɛsɛ sɛ wɔde di dwuma yiye na wɔakwati sɛ wɔde nneɛma a wɔde gyina so ho nsɛm a egyina so no bɛba.
Refactoring ne Access Modifiers .
Refactoring code no betumi ayɛ nsakrae a ɛfa akwan a wɔfa so nya nneɛma a wɔde di dwuma no ho ma nhyehyɛe ne sɛnea wotumi hwɛ so no tu mpɔn.
Nneɛma a wobetumi anya so atew .
Bere a wɔresan asiesie no, susuw ho sɛ wobɛtew asɔremma a wobetumi anya bi afi ɔmanfo hɔ anaasɛ wɔabɔ wɔn ho ban akɔ kokoam sɛ ɛho nhia bio sɛ wobetumi anya kwan a ɛtrɛw a. Saa adeyɛ yi ma encapsulation yɛ kɛse na ɛtew asiane a ɛwɔ hɔ sɛ nkitahodi a wɔanhyɛ da ayɛ so.
Nsakrae a ɛba bere a wɔrebubu no a wɔbɛkwati .
Sɛ woresakra akwan a wɔfa so kɔ hɔ no mu wɔ ɔmanfo API mu a, hwɛ yiye wɔ nsakrae a ɛba no ho. Accessibility a wobɛtew so no betumi ama compilation mfomso aba code a egyina wo API so.
Nsɛmti a ɛkɔ akyiri .
Nsusuwii a ɛkɔ anim a wɔbɛhwehwɛ mu no betumi ama ntease ne dwumadie a ɛfa akwannya mu nsakraeɛ ho no mu ayɛ den.
Access modifiers wɔ design patterns mu .
Design patterns taa kyerɛ akwan pɔtee a wɔfa so kɔ hɔ. Sɛ nhwɛso no, singleton nhyehyɛe no hwehwɛ private constructor a ɛbɛma instantiation amfi adesuakuw no akyi.
Nsakraeɛ wɔ multithreading mu .
Wɔ multithreaded applications mu no, access modifiers di dwuma wɔ thread ahobammɔ mu. Ankorankoro asɔremma betumi asiw nsɛm a ɛfa kwan a wɔfa so kɔ hɔ ho bere koro mu nanso ehia sɛ wonya kwan kɔ hɔ bere a wɔakyekyɛ wɔ nhama so no.
Awie
Nsonsonoeɛ a ɛda ahobanbɔ ne kokoam kwan a wɔfa so kɔ mu no ntam a wɔbɛte aseɛ no ho hia ma adeɛ a wɔde gyina so a ɛfa adeɛ ho a wɔbɛtwerɛ. Bere a private hwɛ ma encapsulation a ɛsen biara no, wɔn ankasa asɔremma a wɔabɔ wɔn ho ban no de kari pɛ ma denam ma a wɔma kwan ma wonya subclass kwan so. Gyinaesi a ɛfata a wosi wɔ akwan a wɔfa so nya nneɛma no ho no ma mmara no ahobammɔ, sɛnea wotumi hwɛ so yiye, ne nea ɛtrɛw no yɛ kɛse.
Ɛdenam nneyɛe pa a wobedi so na wɔasusuw nea nsakrae biara kyerɛ ho so no, wɔn a wɔyɛ no betumi ayɛ softwea nhyehyɛe a ɛyɛ den na ɛyɛ mmerɛw. Leveraging a ɛfata access modifier no yɛ ahokokwaw a ɛho hia a ɛboa ma software nnwuma nyinaa yɛ papa na ɛyɛ yiye.
