Bad String abuse

In this Java Puzzler, it has some serious abuse of Strings, but what is going on?

https://vanilla-java.github.io/2016/04/21/Bad-String.html

Comments

  1. kontiky30 April 2016 at 18:20

    Thank you for the puzzle!

    Unfortunately, I couldn't clearly understand the source of such behaviour. I suppose the the reason is in a way how String Constant Pool selects constants on a base of hashCode() execution. But I'm not sure.

    So will wait for your solution :)

    P.S. could you, please, allow comments and RSS subscription on your GitHub blog?

    ReplyDelete
    Replies
    1. kontiky30 April 2016 at 18:33

      I read that internally String Constant Pool uses Hashtable for storing strings. So looks like equal hashCode() values isn't enough for getting puzzle effect. Also, at the first sight, external synchs on "bb" and "cC" really work on String instance wrappers not on internally char[] arrays...

      So the puzzle is really puzzle :)

      Delete

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