JavaSE面试题——方法的参数传递机制

import java.util.Arrays;
class MyData {
  int a = 10;
}
public class Exam {
  public static void main(String[] args) {
    int i = 1;
    String str = "hello";
    Integer num = 200;
    int[] arr = {1,2,3,4,5};
    MyData my = new MyData();
    change(i,str,num,arr,my);
    System.out.println("i = " + i);
    System.out.println("str = " + str);
    System.out.println("num = " + num);
    System.out.println("arr = " + Arrays.toString(arr));
    System.out.println("my.a = " + my.a);
  }
  public static void change(int i, String str, Integer num, int[] a, MyData m){
    i += 1;
    str += "world";
    num += 1;
    a[0] += 1;
    m.a += 1;
  }
}