In Java Write a DomainName class that encapsulates the conce

In Java Write a DomainName class that encapsulates the concept of a domain name, assuming a domain name has a single attribute: the domain name itself (i.e. www.yahoo.com (Links to an external site.)).

Include the following:

Constructor: accepts the domain name as an argument.//

getDomain: an accessor method for the domain name field.//

setDomain: a mutator method for the domain name field. //

prefix: a method returning whether or not the domain name starts with www. //

extension: a method returning the extension of the domain name (i.e. the letters after the last dot, for instance com, gov, or edu; if there is no dot in the domain name, then you should return \"unknown\")

name: a method returning the name itself (which will be the characters between www and the extension; for instance, yahoo if the domain is www.yahoo.com- (Links to an external site.)--if there are fewer than two dots in the domain name, then your method should return \"unknown\")

. Write a program that demonstrates the DomainName class by prompting the user for the domain name and displays the output of the last three methods.

NOTE: The DomainName class is a new class within your project. This does not affect the name of your Java Project above

Solution

// DomainName.java

public class DomainName {

   private String domainName;
   private String myPrefix;
   private String myExtension;
   private String myName;
  
   public DomainName(String domainName)
   {
       this.domainName = domainName;
       setDomainValues(domainName);
   }
  
   public void setDomainValues(String domainName)
   {
       String[] parts = domainName.split(\"\\\\.\");
      
       /*
       * Question states that if there are fewer than two dots then
       * name is unknown. So with this there should always be three parts
       * prefix name and extension
       * This code was handling cases like
       * yahoo
       * www.yahoo
       * yahoo.com
       * www.yahoo.com
       * Please uncomment if that is expected behaviour
       *
       if (parts.length == 1)
       {
           this.myName = parts[0];
           return;
       }
       if(parts.length == 2)
       {
           if (domainName.startsWith(\"www\"))
           {
               this.myPrefix = parts[0];
               this.myName = parts[1];
           }
           else
           {
               this.myName = parts[0];
               this.myExtension = parts[1];
           }
           return;
       }
       */
       if(parts.length == 3)
       {
           this.myPrefix = parts[0];
           this.myName = parts[1];
           this.myExtension = parts[2];
       }
       else
       {
           this.myPrefix = \"\";
           this.myExtension = \"unknown\";
           this.myName = \"unknown\";
       }
   }
  
   public String getDomain()
   {
       return this.domainName;
   }
  
   public void setDomain(String domainName)
   {
       this.domainName = domainName;
       setDomainValues(domainName);
   }
  
   public boolean prefix()
   {
       return (myPrefix != null && myPrefix.equals(\"www\"));
   }
  
   public String extension()
   {
       if ((myExtension != null) && (!myExtension.isEmpty()))
       {
           return myExtension;
       }
       return \"unkown\";
   }
  
   public String name()
   {
       return myName;
   }
}

// DomainNameTest.java

import java.util.Scanner;
public class DomainNameTest {

   public static void main(String[] args)
   {
       Scanner sc = new Scanner(System.in);
       System.out.print(\"Please enter a domain name: \");
       String domainName = sc.next();
      
       DomainName dm = new DomainName(domainName);
       System.out.println(\"Does domain starts with \'www\': \" + dm.prefix());
       System.out.println(\"Name of the domain: \" + dm.name());
       System.out.println(\"Extension of domain: \" + dm.extension());
   }
}

/*

Sample runs

Please enter a domain name: www.yahoo.com
Does domain starts with \'www\': true
Name of the domain: yahoo
Extension of domain: com

Please enter a domain name: yahoo
Does domain starts with \'www\': false
Name of the domain: unknown
Extension of domain: unknown

Please enter a domain name: www.yahoo
Does domain starts with \'www\': false
Name of the domain: unknown
Extension of domain: unknown

Please enter a domain name: yahoo.com
Does domain starts with \'www\': false
Name of the domain: unknown
Extension of domain: unknown

*/