java——引用类型参数传递

// 引用类型参数public class test1{int num = 1;public static void main(String[] args){int[] arr = new int[]{19, 30};System.out.print("change_pre  arr =");for (int i = 0; i < arr.length; i++) {     System.out.print(arr[i] + ", ");  }  System.out.println();change(arr);System.out.print("change_after  arr =");for (int i = 0; i < arr.length; i++) {     System.out.print(arr[i] + ", ");  }   }static void change(int[] tmpArr){System.out.print("in_change_pre  arr ="); for (int i = 0; i < tmpArr.length; i++) {     System.out.print(tmpArr[i] + ", ");  } System.out.println();int tmp = tmpArr[0];tmpArr[0] = tmpArr[1];tmpArr[1] = tmp;System.out.print("in_change_pre  arr =");for (int i = 0; i < tmpArr.length; i++) {     System.out.print(tmpArr[i] + ", ");  }System.out.println();}}