java中的可变参数使用方法

public class Test{
  public int sum(int... args) {
    int sum = 0;
    for (int arg : args) {
      sum += arg;
    }
    return sum;
  }
}

public class Test{
  public void method(){}
  public void method(int a1){}
  public void method(int a1, int a2){}
  public void method(int a1, int a2, int a3){}
  public void method(int a1, int a2, int a3, int... args){}
}