Question on LAB-1016 Java Collections accessing MyOwnClass in "For Your Own Excercise and Homework

[Jeff Aubert]

Everyone,

When the instructions say to add 2 objects from MyOwnClass, am I loading them individually like this ,

   MyOwnClass moc1 = new  MyOwnClass("Jeff", 55);     // MyOwnClass (String name, Int age);
    
    hs.add(moc1.name);
    hs.add(moc1.age);

or am I adding an object that is the whole class , such as

    MyOwnClass moc1 = new  MyOwnClass("Jeff", 55);     
    MyOwnClass moc2 = new  MyOwnClass("Tom", 48); 
    hs.add(moc1);
    hs.add(moc2); 

If I am supposed to do the second option, i.e., add the instance of the whole class as a collections item, then how do

I correctly interatre through that hash set (or other collection)  ?  Do I a conversion to a string when I print this ?

What are the recommendations for this situation ?

Thank You and Regards,

Jeff

 

[Jeff Aubert]

Everyone,

To iterate through these collections when adding a class object as a collection item, the answer was in some older postings in this group.

I followed the suggestion to Override the toString method within MyOwnClass  :

public String toString() { 

    return this.name + " Age : " +  (this.age) ;

  } 

 

So when assigning who class objects as in this code

 

HashSet hs = new HashSet(); 

hs.add("LSU");  // Sring objects

hs.add("Tigers");

MyOwnClass moc1 = new  MyOwnClass("Jeff", 55);     

MyOwnClass moc2 = new  MyOwnClass("Tom", 48); 

hs.add(moc1);

 hs.add(moc2); 

 

 Integer myInt1 = 100;

 Integer myInt2 = 50;

 Integer myInt3 = 25;

 hs.add(myInt1);  // Integer objects

 hs.add(myInt2);

 hs.add(myInt3);

 

the standard iteration worked

 

System.out.println("Contents of Hash Set");

System.out.println();

for (Iterator i = hs.iterator(); i.hasNext();) {

      System.out.println(i.next());

    }

Example output

 

50

Jeff Age : 55

100

Tom Age : 48

25

Tigers

LSU

 

To those posters from a few years ago, thank you.

Jeff