• 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
  • Devaka Cooray
  • Ron McLeod
  • Jeanne Boyarsky
Sheriffs:
  • Liutauras Vilda
  • paul wheaton
  • Junilu Lacar
Saloon Keepers:
  • Tim Moores
  • Stephan van Hulst
  • Piet Souris
  • Carey Brown
  • Tim Holloway
Bartenders:
  • Martijn Verburg
  • Frits Walraven
  • Himai Minh

initialization

 
Ranch Hand
Posts: 84
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator

output: b = 0

i heard that when we don't specify the constructor
compiler creates the default constructor which intializes
instance variables ...but in this example i created the constructor
and initialized variable a and i didn't initialize variable b..
when i invoke obj.b ..it gives 0 (default value) ..
so where b gets initialized....

 
Saloon Keeper
Posts: 14499
325
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
Static and member variables are always initialized to 0, null, false, etc. before any constructors are executed.
 
Marshal
Posts: 76862
366
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator

saravanan ragunathan wrote: . . . compiler creates the default constructor which intializes instance variables . . .

Whoever told you that was mistaken. The default constructor does nothing at all. As Stephan van Hulst said, that leaves the default values unchanged.
 
saravanan ragunathan
Ranch Hand
Posts: 84
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator

Stephan van Hulst wrote:Static and member variables are always initialized to 0, null, false, etc. before any constructors are executed.



where these variables gets initialized to default values..using default constructor?
 
Stephan van Hulst
Saloon Keeper
Posts: 14499
325
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
No. When you declare a static or member variable, it will have this form:

<Type> <Name> = <Value>.

The value is assigned to the variable before any constructor or initializer is ran.
If you don't supply the = <Value> part, the compiler will more or less add it for you, setting the variable to 0, null, false, etc.
 
Campbell Ritchie
Marshal
Posts: 76862
366
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator

saravanan ragunathan wrote: . . . where these variables gets initialized to default values..using default constructor?

Did you read my earlier posting?
 
Rancher
Posts: 3742
16
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator

Campbell Ritchie wrote:The default constructor does nothing at all.



<pedantic>
It calls its parent's no arg constructor
</pedantic>
 
Campbell Ritchie
Marshal
Posts: 76862
366
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
I take your point, Joanne, but to be pedantic on my part it's a superclass not parent
 
Joanne Neal
Rancher
Posts: 3742
16
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator

Campbell Ritchie wrote:I take your point, Joanne, but to be pedantic on my part it's a superclass not parent



Fair enough. We'll call it a draw this time
 
Campbell Ritchie
Marshal
Posts: 76862
366
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
I'll be happy with a draw; I usually lose to you
 
When all four tires fall off your canoe, how many tiny ads does it take to build a doghouse?
the value of filler advertising in 2021
https://coderanch.com/t/730886/filler-advertising
reply
    Bookmark Topic Watch Topic
  • New Topic