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HashSet will allow null values?  RSS feed

 
Sakthivel Sabapathy
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Can anyone explain me whether HashSet will allow null value or not?
Because in Jamie Jaworski book described as
"It does not allow the use of null element".
 
anrup kris
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I read in the API that HashSet permits null values,where as the class HashTable implements a hashtable and maps keys to values.So it does not permit null values
regards
kris
 
Sakthivel Sabapathy
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So that means Jamie Jaworskie book that specified statement is wrong. Am i right?
 
Sarath Lingamarla
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Sakthivel Sabapathy wrote:So that means Jamie Jaworskie book that specified statement is wrong. Am i right?



HashSet allows null value not null values. it allows only 1 null value per 1 HashSet Object

import java.lang.*;
import java.util.*;
public class Set
{
public static void main(String [] args)
{
Set<Integer> s= new HashSet<Integer>();
s.add(new Integer(5));
s.add(null);
s.add(null);
System.out.println(" "+s.size()+"is the set size");
}
}

Output : 2 is the set size
 
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