Errata - Sybex 829 - Chapter 8

[João Lopes]

Hi,

I think there is an errata on Chapter 8, on the Review Questions:

On the explanation of Question 2 (tb864585.JaSE17SG.c08.02):

1:  interface Climb {
2:     boolean isTooHigh(int height, int limit);
3:  }
4:
5:  public class Climber {
6:     public static void main(String[] args) {
7:        check((h, m) -> h.append(m).isEmpty(), 5);
8:     }
9:     private static void check(Climb climb, int height) {
10:       if (climb.isTooHigh(height, 10))
11:          System.out.println("too high");
12:       else
13:          System.out.println("ok");
14:    }
15: }

Options:
A. ok
B. too high
C. Compiler error on line 7
D. Compiler error on line 10
E. Compiler error on a different line
F. A runtime exception is thrown.

Explanation:

The interface takes two int parameters. The code on line 7 attempts to use them as if h is a String making option C correct. It is tricky to use types in a lambda when they are implicitly specified. Remember to check the interface for the real type.

Shouldn't it be "The code on line 7 attempts to use them as if h is a StringBuilder" ?

Thanks,
João

[Jeanne Boyarsky]

Confirmed and added to the errata. This was wrong in our Java 11 book as well. Have a cow for being the first one to notice!