HashSet with Example


If  our requirement is frequent insert then we go with HashSet.
For efficiency objects added to a HashSet need to implement the hashCode() method in a manner that properly distributes the hash codes. While most system classes override the default hashCode() implementation of the Object.
It is generally faster to add elements to the HasSet then convert the collection to a TreeeSet for sorted traversal.
To optimize HashSet space usage , you can tune initial capacity and load factor.
Example:
public class HashSetExample {

    public static void main(String[] args) {

        HashSet<String> hs=new HashSet<String>();

        // duplicate element is not permitted
        hs.add("b");
        hs.add("a");
        hs.add("c");
        hs.add("d");
        hs.add("d");

        Iterator it=hs.iterator();

        while(it.hasNext())
        {
            String value =(String)it.next();

            System.out.println("Value :"+value);
        }

        System.out.println("Size :"+hs.size());

        hs.remove("d");

        hs.clear();
    }
}
Advertisements
About

I born in Good cultural place called India. My family is traditional family. We fallow all Indian traditions.

Posted in JAVA

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Enter your email address to subscribe to this blog and receive notifications of new posts by email.

Join 678 other followers

Calendar
April 2010
M T W T F S S
« Jul   May »
 1234
567891011
12131415161718
19202122232425
2627282930  
Mallikarjun Gunda

This is Mallikarjun Gunda, I am working as a software professional. Blogging is my Passion. This blog contains the posts on Java related technologies and programming languages. I am happy to share my knowledge through the blogs.

Blog Stats
  • 280,989 hits
IndiBlogger
malliktalksjava.wordpress.c...
70/100