[Java method learning] Variable parameters

variable parameter

• Starting with JDK 1.5, Java supports passing variable parameters of the same type to a method.

• In the method declaration, add an ellipsis (···) after the specified parameter type . –> test(int…i)

• Only one variable parameter can be specified in a method, and it must be the last parameter of the method . Any ordinary parameters must be declared before it.

public static void main(String[] args) {
    
    
    Demo04 demo04 =new Demo04();
    demo04.test(2,3,4,0,90);     //通过demo04来调用test
}
public void test(int...i){
    
    
    System.out.println(i[0]);
    System.out.println(i[1]);
    System.out.println(i[2]);
    System.out.println(i[3]);
    System.out.println(i[4]);//最后输出竖着排列的 2,3,4,0,90
}

  public static void main(String[] args) {
    
    
        //调用可变参数的方法
        printMax(38,40,2,403,39.3,39);
        printMax(new double[]{
    
    1,2,3});

        /*最后输出结果是：
         The max value is403.0
         The max value is3.0
         */

    }
    public static void printMax(double... numbers){
    
    
        if (numbers.length==0){
    
    
            System.out.println("No argument passed");
            return;
        }
        double result =numbers[0];

        //排序
        for (int i=1;i<numbers.length;i++){
    
    
            if (numbers[i]>result){
    
    
                result = numbers[i];
            }
        }
        System.out.println("The max value is" +result);
    }
}