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Index › Programming Questions & Help › Syntax Questions › Siblings of objects, best method
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Siblings of objects, best method? (Read 512 times)
knutEinar
Siblings of objects, best method?
Jan 24th, 2010, 4:35am  
I am trying to figure out a way to have objects 'talk to' their siblings. Is there a well known 'best practice' way of doing this? I know I can loop through arrays, store the values, and pass them on to the next object. But I wonder if it is possible to do this in a more elegant way, preferably from inside the object itself (if this is not a big no-no for some reason). As far as I know, there is no generic method for this, like 'this.nextSibling' or something like that? But I'm thinking it would be possible to do this using an index-number, and then check if there are objects with index numbers above or below this one. But before I start testing this out, does anyone have any experience/hints on this topic? Is what I'm doing/thinking 'the wrong way'?
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TfGuy44
Re: Siblings of objects, best method?
Reply #1 - Jan 24th, 2010, 5:14am  
There is a preferred way, and it is to pass to the object the array of objects that the object itself is contained in. For example:

Quote:
class TryNextDoor {
  boolean hasSugar;
  int myAddress;
  TryNextDoor theStreet[];
  TryNextDoor( boolean has, int address, TryNextDoor [] street ){
    hasSugar = has;
    myAddress = address;
    theStreet = street;
  }
  void ask(String message){
    if( hasSugar ){
      println( myAddress + ": I have some!" );
    }
    else{
      if( myAddress+1 < theStreet.length ){
        println( myAddress +  ": Nope. Try asking next door! " + message + myAddress );
        theStreet[myAddress+1].ask(message + myAddress);  
      }
      else {
         println( myAddress +  ": I guess no one has any. " + message + myAddress );
      }
    }
  }
}

TryNextDoor myNeighborhood[];

void setup(){
  myNeighborhood = new TryNextDoor[10];
  for( int i = 0; i < myNeighborhood.length; i++ ){
    myNeighborhood[i] = new TryNextDoor( false, i, myNeighborhood );
  }

  myNeighborhood[0].ask("");

}

void draw(){
}



Does that help clear things up at all?  Huh
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« Last Edit: Jan 24th, 2010, 8:06am by TfGuy44 »  
 
knutEinar
Re: Siblings of objects, best method?
Reply #2 - Jan 24th, 2010, 5:32am  
Yes, exactly what I was wondering about Smiley So by passing the whole array, you have access to all the properties/instance variables of all the objects (which would be all the siblings) in that array? I will play with your example for a while, and see if I get the results I am expecting, and if not I will come back for help! Smiley Would you say this is an advanced use of objects, or is it pretty basic stuff? Cheers! Cheesy
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PhiLho 
Re: Siblings of objects, best method?
Reply #3 - Jan 24th, 2010, 6:01am  
What TfGuy44 said, except I would have used an ArrayList...
Or perhaps LinkedList.
If you use an Iterator over the collection, then you have a "natural" concept of next element, including hasNext(), next() or even nextIndex() for ListIterator.
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