Hi guys,
I need to build a Cache Object on a Web server.
So I want to use the Singleton design pattern.

So I need some resources, documentation and exemples on the Singleton pattern.
Any links to resources will be welcome.

Thank you.
Stan

this is an exemple of implementation of Singleton PATTERN
if you want to access to your singleton

MyClassSingleton singleton = MyClassSingleton.getInstance();
singleton.method1();

/*************/
public class MyClassSingleton {

private static MyClassSingleton instance;

//Constructor must be protected or private to perevent creating new object
protected MyClassSingleton() {

}
//could be synchronized
public static MyClassSingletongetInstance() {
         if (instance==null)
                  instance = new MyClassSingleton()
return instance;

}
public void method1(){
  System.out.println("hello singleton");
}
}//end of class

To avoid thread safety issues:

public class Singleton {
  private static final Singleton INSTANCE = new Singleton();
  private Singleton() {
  }

  public static Singleton getInstance() { return INSTANCE; }
}

/**
 * @author Sonjoy Chakraborty
 *
 */
public class SingletonClass {

 private static final SingletonClass oSingletonClass = new SingletonClass();
 public int i = 0;

 public int getI() {
  return i;
 }

 public void setI(int i) {
  this.i = i;
 }

 private SingletonClass() {
  // TODO Auto-generated constructor stub
 }

 public static synchronized SingletonClass getInstance() {
  return oSingletonClass;
 }

}

 

// Now real implementation [ to confirm that the same instance is in all the cases. ]

 

 

/**

*

@author

Sonjoy

Chakraborty

*

*/

public

 

 

 

/**

*

*/

 

public TestSingleton() {

 

// TODO Auto-generated constructor stub 

 

oSingletonClass.setI(10);

}

 

 

public void TestSingletonX() {

 

// TODO Auto-generated constructor stub

SingletonClass oSingletonClassX = SingletonClass.getInstance();

System.

out.println(oSingletonClassX.getI());

}

 

 

/**

*

@param

args

*/

 

public static void main(String[] args) {

 

// TODO Auto-generated method stub

TestSingleton oTestSingleton =

new TestSingleton();

oTestSingleton.TestSingletonX();

}

 

}

class TestSingleton {

SingletonClass oSingletonClass = SingletonClass.getInstance();

}

}

public static void main(String[] args) {

 // TODO Auto-generated method stub

 

TestSingleton oTestSingleton = new TestSingleton();

oTestSingleton.TestSingletonX();

}

There are many approaches to implement the Sigleton Design Pattern like Eager Initialization,Lazy Initialization,static block initialization,Thread safe singleton

If anybody wants to know all these approaches in detail then please go through this blog http://adnjavainterview.blogspot.in/2014/06/singleton-design-pattern-in-java-with.html