tillu

 Profile Answers by tillu 

• Feb 12th, 2006

 

the class which contains single method is called singleton class

M Manish

• Feb 13th, 2006

 

Hi,

Singleton Design pattern helps us to have only one instance of a class in the entire JVM(for a class-loader) and provides global one-point access to it.

There are several ways to achieve this:

1.

public class Singleton

{

Manish

• Feb 13th, 2006

 

Sorry, the post went wrongly

To continue...

public class Singleton{

private static Singleton uniqueInstance;

/*Make a private Contructor. This would ensure that no-one can make an instance of Singleton from outside*/

private Singleton(){}

public static synchronized SingletongetInstance()

{

    if(uniqueInstance==null)

{

    uniqueInstance=new Singleton();

   }

   return uniqueInstance;

   }

//your normal methods go here...

}

2. Make an instance of Singleton when the JVM loads the class:

public class Singleton

{

  private static Singleton uniqueInstance=new Singleton();

  private Singleton(){}

  public static Singleton getInstance()

  {

     return uniqueInstance;

  }

}

I believe this should help you to create a Singleton class.

Srihari

• Feb 14th, 2006

 

Singleton is one and only one instance of a Class for a class loader, which is used by all users of application.

Public class Singleton {

  Singleton singleton = null;

  private Singleton () {} // Inportant 

  public static Singleton synchronized getSingletonInstance() {

      if(singleton ==null )

  }

}

JavaProgramer

• Feb 14th, 2006

 

Singleton design pattern is used to make one and only one instance of a specific class, which can be used by all users of the application.

Public Class Singleton {

  private static Singleton singleton = null; 

  Private Singleton(){} //Important

  public static Singleton synchronized getSingletonInstance() {

    if(singleton ==nul)

      singleton = new Singleton();

    return singleton;

  }

  public void businessMethod() {

     /*

      Write any Business logic here

    */

  }

   public Object clone() throws CloneNotSupportedException {

    raise new CloneNotSupportedException();
    }

}

get_manishpatel

 Profile Answers by get_manishpatel 

• Feb 18th, 2006

 

When developer of the class doesn't want to allow the user to create more than one object he will create class such a way that no one can create more than one object of that class

class SingalTone{
private static SingalTone st;
private SingalTone(){
 System.out.println("SingalTone object is created !!");
}
static{
 st = new SingalTone();
}
public static SingalTone createObject(){
 return st;
}
}
public class STTest{
public static void main(String args[]){
 SingalTone st1,st2,st3;
 st1 = SingalTone.createObject();
 st2 = SingalTone.createObject();
 st3 = SingalTone.createObject();
 System.out.println("st1.hashCode() --> "+st1.hashCode());
 System.out.println("st2.hashCode() --> "+st2.hashCode());
 System.out.println("st3.hashCode() --> "+st3.hashCode());
 }
}

Shahid mohammed

• Mar 19th, 2006

 

If we want to give security or if we want the only one instance of a class must be created then we go for singletonobject.

Guest

• Mar 22nd, 2006

 

Hi All,

Generally Singleton Pattern is used while accessing database related objects. It provides one point access to whole java application. It makes sense to make it thread safe by use of synchronized keyword.

Regards

-ashruf

rams_k

 Profile Answers by rams_k 

• May 10th, 2006

 

if we dont wnat a class to be subclassed or only one obj to be created go for singletone it only allows only one obj to be createdand rest of them to use that obj for example

Public Class Singleton {

  private static Singleton singleton = null; 

  Private Singleton(){} //Important

  public static Singleton synchronized getSingletonInstance() {

    if(singleton ==nul)

      singleton = new Singleton();

    return singleton;

  }

so here we cant access aprivate constructor if there is obj it returns that else creates a new one as we r declaring class as public we can call that class and instance method is static we can call directly without obj.The singletone will b used mainly when only one obj to b created for appl,for ex if we want only one database connection for our appl go for the singletone

i think iam correct...i welcome my mistakes and guys help me out if iam wrong

contact me @ ramu.konkimalla@gmail.com