Win a copy of High Performance Python for Data Analytics this week in the Python forum!
  • Post Reply Bookmark Topic Watch Topic
  • New Topic
programming forums Java Mobile Certification Databases Caching Books Engineering Micro Controllers OS Languages Paradigms IDEs Build Tools Frameworks Application Servers Open Source This Site Careers Other all forums
this forum made possible by our volunteer staff, including ...
Marshals:
  • Campbell Ritchie
  • Paul Clapham
  • Ron McLeod
  • Bear Bibeault
  • Liutauras Vilda
Sheriffs:
  • Jeanne Boyarsky
  • Tim Cooke
  • Junilu Lacar
Saloon Keepers:
  • Tim Moores
  • Tim Holloway
  • Stephan van Hulst
  • Jj Roberts
  • Carey Brown
Bartenders:
  • salvin francis
  • Frits Walraven
  • Piet Souris

Errata for OCP: Oracle Certified Professional Java SE 8 Programmer II Study Guide - page 146

 
Ranch Hand
Posts: 238
5
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
Page 146, "compareTo() and equals() Consistency" box.

In the last paragraph, "You might be sorting Product objects by name, but names are not unique. Therefore, the return value of compareTo() might not be 0 when comparing two equal Product objects (...)"

should read: "You might be sorting Product objects by name, but names are not unique. Therefore, the return value of compareTo() might be 0 when comparing two non-equal Product objects (...)"


 
T Vergilio
Ranch Hand
Posts: 238
5
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
And a small typo on page 149: "If two squirrels are from the species" should read "If two squirrels are from the same species".
 
author & internet detective
Posts: 40400
821
Eclipse IDE VI Editor Java
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
I agreed with the comment on page 149 and have logged it.

I think the one on page 146 is correct. Consider:



The two objects are equal but have a compareTo value other than 0. Your statement is true. And equally a problem. But the way the book phrases it isn't wrong. It just goes with a different example than yours. And either way, the point is the same. Don't do that!
 
T Vergilio
Ranch Hand
Posts: 238
5
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
Indeed, the message is the same either way. I assumed id would be unique, but there is nothing in the code to suggest that. Thanks for checking.
 
He was giving me directions and I was powerless to resist. I cannot resist this tiny ad:
the value of filler advertising in 2020
https://coderanch.com/t/730886/filler-advertising
reply
    Bookmark Topic Watch Topic
  • New Topic