• 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 Pie Elite all forums
this forum made possible by our volunteer staff, including ...
Marshals:
  • Campbell Ritchie
  • Tim Cooke
  • paul wheaton
  • Jeanne Boyarsky
  • Ron McLeod
Sheriffs:
  • Paul Clapham
  • Liutauras Vilda
  • Devaka Cooray
Saloon Keepers:
  • Tim Holloway
  • Roland Mueller
Bartenders:

Solution for Exercise 9.2 (K&B)

 
Ranch Hand
Posts: 96
  • Likes 1
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
Text reads:
In this exercise we will attempt to synchronize a block of code. Within that block of
code we will get the lock on an object, so that other threads cannot modify it while
the block of code is executing. We will be creating three threads that will all attempt
to manipulate the same object. Each thread will output a single letter 100 times, and
then increment that letter by one. The object we will be using is StringBuffer.
We could synchronize on a String object, but strings cannot be modified once
they are created, so we would not be able to increment the letter without generating
a new String object. The final output should have 100 As, 100 Bs, and 100 Cs all in
unbroken lines.

My Solution:


is this what you guys had also? it does print 100A's 100B's and 100C's in that order
 
Sheriff
Posts: 9708
43
Android Google Web Toolkit Hibernate IntelliJ IDE Spring Java
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
Bhaarat your solution is valid and right. However I think the authors meant to synchronize on the StringBuffer object (that is why they didn't use a String). So if you change synchronized(this) to synchronized(s), that would be the correct answer too...
 
Greenhorn
Posts: 11
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
at the and of the chapter 9 (at least in Java 5 version) there is a sample solution which looks quite like yours with the exception that the synchronization is on StringBuffer - just as Ankit said above.
 
Ranch Hand
Posts: 310
1
Oracle Java Linux
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
nice code Bhaarat!
 
Greenhorn
Posts: 8
Hibernate Eclipse IDE Linux
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
This is what I had tried..
 
Please do not shoot the fish in this barrel. But you can shoot at this tiny ad:
New web page for Paul's Rocket Mass Heaters movies
https://coderanch.com/t/785239/web-page-Paul-Rocket-Mass
reply
    Bookmark Topic Watch Topic
  • New Topic