Win a copy of Kotlin for Android App Development this week in the Kotlin forum!
    Bookmark Topic Watch 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
  • Liutauras Vilda
  • Devaka Cooray
  • Jeanne Boyarsky
  • Bear Bibeault
Sheriffs:
  • Junilu Lacar
  • Paul Clapham
  • Knute Snortum
Saloon Keepers:
  • Ron McLeod
  • Tim Moores
  • Stephan van Hulst
  • salvin francis
  • Carey Brown
Bartenders:
  • Tim Holloway
  • Frits Walraven
  • Ganesh Patekar
  • Likes 3
  • Mark post as helpful
  • send pies
  • Report post to moderator
Why does this code produce the output "0" instead of "1"?





Let's take a close look at what the line "i = i++;" does:


  • "i++" is evaluated. The value of "i++" is the value of i before the increment happens.
  • As part of the evaluation of "i++", i is incremented by one. Now i has the value of 1;
  • The assignment is executed. i is assigned the value of "i++", which is the value of i before the increment - that is, 0.


  • That is, "i = i++" roughly translates to



    With other words, it is a common misconception that the increment is happening last. The increment is executed immediately when the expression gets evaluated, and the value before the increment is remembered for future use inside the same statement.

    Solution:

    You don't need the assignment at all, just use



    Reason:

    The post-increment operator increments the value of your integer "i" after the execution of your "System.out..." statement so use "++i" (pre-increment operator)..




    See also

  • https://docs.oracle.com/javase/specs/jls/se8/html/jls-15.html#jls-15.14.2
  • http://www.coderanch.com/t/244938/java-programmer-SCJP/certification/post-increment-confusion
  • http://web.archive.org/web/20070305125534/http://radio.javaranch.com/corey/2004/06/03/1086277171000.html

  •  
    No, tomorrow we rule the world! With this tiny ad:
    Programmatically Create PDF Using Free Spire.PDF with Java
    https://coderanch.com/wiki/703735/Programmatically-Create-PDF-Free-Spire
      Bookmark Topic Watch Topic
    • New Topic
    Boost this thread!