equals hashcode

[Alfred Nobel]

I have created a Class

Class A implements Comparable{
String id;
Date d;
@override
compareTo(ClassA obj){
return this.d.compareTo(obj.)
}
public Date getDate(){
return d;
} 
public String getId(){
return id;
}
}
   

I am using this object in Arraylist and sorting the list based on this. Then i am adding the list of this objects(List<ClassA> to HashSet, Then i am populating another List<ClassA> if it is not there in hashset.


The question here is should i have to implement equals and hashcode methods in ClassA. If so caan anyone give an efficient equal and hashcode impl code.

Thanks in advance

[Jeanne Boyarsky]

Manoj,
The first step is to define what you want object equality to mean. (just id or all fields, what level of granularity for the date)

Note that nobody here will write your code for you. We will help you so do feel free to post your first attempt here for comments/direction.

[Pankaj Mittal]

This code means you want to sort A class's objects array....

No you don't need to implement either of these methods because you are comparing on basis of date and date already has these methods.

[Amit Ghorpade]

Hi Manoj lal please UseAMeaningfulSubjectLine
"equals hashcode" makes little or no sense at all.

Also please take some time to read the ask good questions link below.


Hope this helps