在程序中打印出程序堆栈的信息

package exception;

import java.util.Scanner;

public class StackTraceTest {
 public static int factorial(int n) {
  System.out.println("factorial(" + n + "):");
  
  //打印出程序调用的信息
  Throwable t = new Throwable();
  StackTraceElement[] frames = t.getStackTrace();
  for(StackTraceElement f : frames) {
   System.out.println(f);
  }
  
  int r;
  if(n <= 1) {
   r = 1;
  } else {
   r = n * factorial(n - 1);
  }
  System.out.println("return " + r);
  
  return r;
 }
 
 public static void main(String[] args) {
  Scanner in = new Scanner(System.in);
  System.out.println("Please input a number: ");
  int n = in.nextInt();
  factorial(n);
 }
}