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Questions tagged [implements]

`implements` is a keyword in several programming languages used to denote implementation of an interface.

implements is a keyword in several programming languages which support OOP (such as Java or PHP) used to denote interface implementation (as opposed to extends used to denote implementation inheritance).

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"implements Runnable" vs "extends Thread" in Java

From what time I've spent with threads in Java, I've found these two ways to write threads: With implements Runnable: public class MyRunnable implements Runnable { public void run() { //Code } } //Started with a "new Thread(new…
user65374
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Implements vs extends: When to use? What's the difference?

Please explain in an easy to understand language or a link to some article.
Saad Masood
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What's the difference between 'extends' and 'implements' in TypeScript

I would like to know what Man and Child have in common and how they differ. class Person { name: string; age: number; } class Child extends Person {} class Man implements Person {}
davejoem
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Extending vs. implementing a pure abstract class in TypeScript

Suppose I have a pure abstract class (that is, an abstract class without any implementation): abstract class A { abstract m(): void; } Like in C# and Java, I can extend the abstract class: class B extends A { m(): void { } } But unlike in…
Michael Liu
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Interface extends another interface but implements its methods

In java when an interface extends another interface: Why does it implement its methods? How can it implement its methods when an interface can't contain a method body How can it implement the methods when it extends the other interface and not…
GingerHead
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Why "extends" precedes "implements" in class declaration

Why must implement always be written after extend in a class declaration? For example: public class Register extends ActionSupport implements ModelDriven Why can it not be: public class Register implements ModelDriven extends ActionSupport The…
lzjun
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Best way to implement View.OnClickListener in Android

Suppose we have an Activity with a lot of views on which OnClickListener is to be registered. The most common way to implement this is to let the Activity-Subclass implement the OnClickListener, something like this: public class ActivityMain extends…
Sarthak Mittal
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extends and implements in one class in TypeScript

Can I do this in TypeScript? export interface IMyInterface { doSomething(): void; } export class MyBaseClass { myBaseClassHasProperty: string; constructor(){ this.myBaseClassHasProperty = 'some value'; } myBaseClassHasMethods(): void…
Everton Santos
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How many interfaces can a class implement in PHP?

I'm looking for an answer to question which is not difficult, but I can't find out how many interfaces can be implemented by one class. Is this possible? class Class1 implements Interface1, Interface2, Interface3, Interface4 { ..... } For all…
Arnas Pečelis
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extends class and implements interface in java

interface Bouncable{ } interface Colorable extends Bouncable{ } class Super implements Colorable{ } class Sub extends Super implements Colorable {} // Ok (case -1) But, class Sub implements Colorable extends Super {} // error (case -2) Why…
Ravi
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Check if a generic T implements an interface

so I have this class in Java: public class Foo{ } and inside this class I want to know if T implements certain interface. The following code DOES NOT work but it's the idea of what I want to accomplish: if(T.class implements SomeInterface){ …
Budius
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How to force implementation of a method in subclass without using abstract?

I want to force subclass to implement an implemented method of my mother class. I look this Java - Force implementation of an implemented method but i can't convert my mother class to an abstract class. public class myMotherClass { myMethod { …
Maniz
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What's the difference between the implements & extends keywords in Java

What's the difference between the following keywords in Java: implements, extends?
sachin
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TypeScript class implements class with private functions

I was exploring the possibility of having a class implementing a class in TypeScript. Hence, I wrote the following code Playground link: class A { private f() { console.log("f"); } public g() { console.log("G"); } } class B implements A { …
Radu Szasz
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Behavior of strictfp keyword with implementing/extending an interface/class

JLS strictfp Interfaces specifies that : The effect of the strictfp modifier is to make all float or double expressions within the interface declaration be explicitly FP-strict (§15.4). This implies that all nested types declared in the interface…
Naruto Biju Mode
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