java可变参数

package exercise03_jdknews;import java.util.ArrayList;import java.util.Scanner;/** * 可变参数 * 格式 *      修饰符 返回值类型 方法名(数据类型... 变量名){} * @author lgt * */public class KebianCanShu {    public static void main(String[] args) {        int a = 20;        int b = 23;        int result1 = sum(a,b);        System.out.println(result1);        //可变参数的调用类型        System.out.println("可变参数的调用类型");        System.out.println(sum1(1,2,3,4,5,6,7,8,9,10));        int[] i1 = {1,23, 32,3};        int[] i2 = {2,3,4,5,6,7,8,9,10};        int[] i3 = {1,2,3,4,5,6,7,8,9,10};        System.out.println("参数个数为：" + i1.length + "，sum1(i1) 其和为：" + sum1(i1));        System.out.println("参数个数为：" + i2.length + "，sum1(i2) 其和为：" + sum1(i2));        System.out.println("参数个数为：" + i3.length + "，sum1(i3) 其和为：" + sum1(i3));        //输入几个整数，求和，个数不确定方式2        System.out.println("输入几个整数，求和，个数不确定方式2");        Scanner sc = new Scanner(System.in);        ArrayList<Integer> list = new ArrayList<Integer>();        while(true){            Integer x = sc.nextInt();            if(x != 0){                list.add(x);            }else{                break;            }        }        sc.close();        System.out.println(sum2(list));    }    public static int sum(int a, int b){        return a+b;    }    public static int sum1(int... a){        int sum = 0;        for(int i : a){            sum += i;        }        return sum;    }    public static Integer sum2(ArrayList<Integer> list){        Integer sum = 0;        for(Integer i : list){            sum += i;        }        return sum;    }}