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How to add the objects to the arraylist class if object has many states

 
upanshu vaid
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Hi,
In this below code I want to do that once I set the state of the object I want to add that object to the arraylist

kindly help on this
 
K. Tsang
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Your line 5 should have read


Then after you have got the inputs after line 19, add the "sort" to the array list ar.

Don't know why you will need an array (line 6) and a list (line 5) given the list is Sort type.
 
upanshu vaid
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Thanks for your reply
one more quick ?



comparator class


How can I make comparator to sort according to and according to sex
 
upanshu vaid
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How can I make comparator to sort according to name and according to sex
 
K. Tsang
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You want to compare name THEN sex or either name or sex?

If either, then you need 2 comparators one for each. If both, then check if names are equals then check sex.

 
Winston Gutkowski
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upanshu vaid wrote:How can I make comparator to sort according to name and according to sex

You were a whisker away from it with the comparator you just wrote, but then you returned 'name'.

As K.Tsang said, if you want to order by name THEN sex, then the sex comparison only needs to be done if the names are equal.

The problem is that, for any Comparable object, there are TWO ways of determining if they are "equal":
1. equals() returns true.
2. compareTo() returns 0.
And there is nothing that requires that the two methods work the same (although it's usually a good idea if they do).

Since your Comparator is creating an order, it makes sense to me to use compareTo(), since it is the method that provides an order; so putting all that together, you get (from your own method):or something very like it.

See how close you were?

Winston
 
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