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Thread: Objects

  1. #1
    Java kindergarten chronoz13's Avatar
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    Default Objects

    i just want to ask this for some clarification

     
    myObjectOne = myObjectTwo.getTheValue(); // assuming this method returns an object(reference(

    in the sample code.. what is myObjectOne? is it the receiving object? or is it the calling object that refers to the returned object value?

    what is myObjectTwo? is it the receiving object? or is it the calling object that calls the method?


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    Super Moderator helloworld922's Avatar
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    Default Re: Objects

    myObjectOne is the receiving object. It's "receiving" the object reference from the method getTheValue(). myObjectTwo is the calling object, and any data associated with it can be used by the getTheValue() method.

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    chronoz13 (January 20th, 2010)

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    Java kindergarten chronoz13's Avatar
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    Default Re: Objects

    something is confusing here.. the book says the reserved word "this" is used to refer to the receiving object

    for example
    myObjectOne.doThisMethod();


    inside the doThisMethod()
    // assuming that these are the codes inside the doThisMethod();
     
    public voi doThisMethod() {
     
      this.getTheFirstValue();
      this.getTheSecondValue();
    }

    in this case the reserved word this is reffering to the myObjectOne object...

    does the book teaching me somethin confusing?

    by the way.. this is my exact assumption on what the book have said....

    that the reserved word "this" is used to refer to the receiving object

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    Super Moderator Json's Avatar
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    Default Re: Objects

    No you use the keyword this inside your class to represent the instance of the class itself. For instance take a simple getter method.

    public class Test {
     
        private String string;
     
        public String getString() {
            return [b]this[/b].string;
        }
    }

    Here you can see that the keyword this is referring to this instance of the class and it then returns the member called string from it.

    // Json

  6. #5
    Java kindergarten chronoz13's Avatar
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    Default Re: Objects

    oh i forgot to include this.. assuming that the myObjectOne is an instance of its class...

    darn... the book is a bit confusing...

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    Super Moderator helloworld922's Avatar
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    Default Re: Objects

    Even if you have multiple instances of an object, this will always refer to the current object the method is being called from.

    public class Demo
    {
         String toDisplay;
         public Demo(String toDisplay)
         {
              this.toDisplay = toDisplay;
         }
     
         public void display(Demo demo2)
         {
              System.out.println("I'm displaying this demo's toDisplay: " + this.toDisplay);
              System.out.println("Now displaying demo2's toDisplay: " + demo2.toDisplay);
         }
     
         public static void main(String[] args)
         {
              Demo d1 = new Demo("demo1");
              Demo d2 = new Demo("demo2");
              d1.display();
          }
    }

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