Java 中的接口可以扩展多个接口吗?
Java 中的接口类似于类,但是只包含抽象方法和字段,它们是 final 的和静态的。就像类一样,你可以使用 extends 关键字让一个接口从另一个接口中扩展,如下所示
interface ArithmeticCalculations { public abstract int addition(int a, int b); public abstract int subtraction(int a, int b); } interface MathCalculations extends ArithmeticCalculations { public abstract double squareRoot(int a); public abstract double powerOf(int a, int b); }
同理,你可以使用 extends 关键字让一个接口从多个接口中扩展,使用逗号 (,) 分隔接口,如下所示:-
interface MyInterface extends ArithmeticCalculations, MathCalculations {
示例
以下 Java 程序演示了如何让一个接口从多个接口中扩展。
import java.util.Scanner; interface ArithmeticCalculations { public abstract int addition(int a, int b); public abstract int subtraction(int a, int b); } interface MathCalculations { public abstract double squareRoot(int a); public abstract double powerOf(int a, int b); } interface MyInterface extends MathCalculations, ArithmeticCalculations { public void displayResults(); } public class ExtendingInterfaceExample implements MyInterface { public int addition(int a, int b) { return a+b; } public int subtraction(int a, int b) { return a-b; } public double squareRoot(int a) { return Math.sqrt(a); } public double powerOf(int a, int b) { return Math.pow(a, b); } public void displayResults() { Scanner sc = new Scanner(System.in); System.out.println("Enter the value of a: "); int a = sc.nextInt(); System.out.println("Enter the value of b: "); int b = sc.nextInt(); ExtendingInterfaceExample obj = new ExtendingInterfaceExample(); System.out.println("Result of addition: "+obj.addition(a, b)); System.out.println("Result of subtraction: "+obj.subtraction(a, b)); System.out.println("Square root of "+a+" is: "+obj.squareRoot(a)); System.out.println(a+"^"+b+" value is: "+obj.powerOf(a, b)); } public static void main(String args[]) { new ExtendingInterfaceExample().displayResults(); } }
输出
Enter the value of a: 4 Enter the value of b: 3 Result of addition: 7 Result of subtraction: 1 Square root of 4 is: 2.0 4^3 value is: 64.0
广告