Interface yana bayyana kwangila — jerin hanyoyin da wani iri dole ya bayar — tare da kaɗan ko babu aiwatarwa. Abstract class shi ne aji da aka aiwata waje-waje wanda zai iya riƙe jiya na gida da hanyoyin sakamako amma ba zai iya zama ba. Bambanci mai mahimmanci: aji zai iya aiwatar da yawa interfaces amma ya derhe daga aji gida daya kawai.
| Interface | Abstract class |
|---|
| Za a iya rikinta | A'a | A'a |
| Harena masu yawa | Ee (aiwatar da yawa) | A'a (tushe gida) |
| Filayen / jiya | A'a (abokin tabbaci kawai*) | Ee |
| Jikin hanya | Hanyoyin tsohuwar (default) kawai* | Ee, gaba daya |
| Tsari | Karɓa ("zai iya gida") | Shine tare da kodun haɗin gida |
*Sabuwar Java zata ba da damar hanyoyin default da abokin tabbaci; jiya ya sake riƙa.
interface Drawable { // a capability
void draw();
}
abstract class Shape { // shared identity + state
protected String color;
Shape(String color) { this.color = color; }
abstract double area(); // subclasses must define
String describe() { // shared concrete behavior
return color + " shape, area=" + area();
}
}
class Circle extends Shape implements Drawable {
private double r;
Circle(String c, double r) { super(c); this.r = r; }
double area() { return Math.PI * r * r; }
public void draw() { /* render */ }
}
Circle shine Shape (tushe gida, kodun haɗin gida) kuma zai iya zama Drawable (karɓar haɗa).
Zabar ba daidai ba ya kulle saman ƙira: tushe abstract yana tilasta layin harena gida daya, yayin da interface zai bar iri na ̀ jiya don haɗa karɓa.
Interface su ne zaɓin tsohuwa don sakowa gida — dogaro akan kwangila maimakon tsarin gida tunani yana ajiye kodun azaman jarrabawa da fadada.