添加corejava第11版源码

日期：2019-5-22

corejava第11版/v1ch07/stackTrace/StackTraceTest.java

@@ -0,0 +1,38 @@
+package stackTrace;
+
+import java.util.*;
+
+/**
+ * A program that displays a trace feature of a recursive method call.
+ * @version 1.10 2017-12-14
+ * @author Cay Horstmann
+ */
+public class StackTraceTest
+{
+   /**
+    * Computes the factorial of a number
+    * @param n a non-negative integer
+    * @return n! = 1 * 2 * . . . * n
+    */
+   public static int factorial(int n)
+   {
+      System.out.println("factorial(" + n + "):");
+      var walker = StackWalker.getInstance();
+      walker.forEach(System.out::println);      
+      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)
+   {
+      try (var in = new Scanner(System.in))
+      {
+         System.out.print("Enter n: ");
+         int n = in.nextInt();
+         factorial(n);
+      }
+   }
+}