可變引數

實際上引數是陣列

public class MethodDemo07 {
    public static void main(String[] args) {
        MethodDemo07 demo07 = new MethodDemo07();
        demo07.test(1,2,3,4,5,6,7,8,9);
    }

    public void test(int... numbers) {
        for ( int i = 0; i < numbers.length; i++ ) {
            System.out.println("第" + (i+1) + "個值為：" + numbers[i]);
        }
    }
}
 

public class MethodDemo08 {
    public static void main(String[] args) {
        MethodDemo08 demo08 = new MethodDemo08();
        demo08.printMax();
        //demo08.printMax(2.5,3.5,1.2,8.9,4.2);
    }

    public void printMax(double... numbers) {
        if ( numbers.length == 0 ) {
            System.out.println("未傳遞任何引數");
            return; //結束標誌
        }

        double results = numbers[0];
        //排序
        for ( int i = 0; i < numbers.length; i++ ) {
            if ( numbers[i] > results ) {
                results = numbers[i];
            }
        }

        System.out.println("最大的數為：" + results);
    }
}
 

當沒有傳遞引數時：

傳遞引數時：