Bonus task | Lesson 13 | Level 6

I've to say: it was a bit of a challenge

Output: Thread 1: My exception message Thread 2: My exception message

Multi-threading is like getting bit by a radioactive spider. Things will be weird for a while, hard to adapt to. Ultimately, it's when you got your superpowers.

In Clew task, hint will just throw you out of track (Thread 4 can be checked using isAlive()).

In Creating threads recursively, why Thread.currentThread().getName() isn't validated in toString method?

In first Consecutive threads task first comment "//write your code here" is placed inappropriately.

task1631 (Factory method pattern) pitfall: the task turned up another dark corner of the language, which is that switch statements explode if presented with a null value. This is somewhat suprising since there is no dereferencing of any pointers involved, only comparison of pointer values. A chained if statement with operator == would not exhibit such weird behaviour. Anyway, this is relevant to the task at hand because there is a specific requirement which exception should be thrown for any illegal arguments.

task1630 (Sequential file output) undocumented requirement: your code will be failed unless it reacts to invalid inputs by printing an empty string instead of null or whatever (i.e. the content of a non-existing file is deemed to be "").

task1626 (Following a pattern) caveat: you will get failed if you 'follow the pattern' (i.e. if you emulate the broken logic of the CountdownRunnable code as you are told) because it runs afoul of the requirement "The CountUpRunnable class's run method should run for approximately 2.5 seconds". I bet on the wrong horse and lost - don't follow my pattern. 😉

That moment when one completes all the easy and medium tasks and has to face the hard tasks...