How to implement or use the singleton class in java?
Answer Posted / pinaki mukherjee
A singleton is an object that cannot be instantiated. At
first, that might seem counterintuitive - after all, we need
an instance of an object before we can use it. Well yes a
singleton can be created, but it can't be instantiated by
developers - meaning that the singleton class has control
over how it is created. The restriction on the singleton is
that there can be only one instance of a singleton created
by the Java Virtual Machine (JVM) - by prevent direct
instantiation we can ensure that developers don't create a
second copy.
We'll start with the class definition, for a SingletonObject
class. Next, we provide a default constructor that is marked
as private. No actual code needs to be written, but you're
free to add some initialization code if you'd like.
public class SingletonObject
{
private SingletonObject()
{
// no code req'd
}
}
So far so good. But unless we add some further code,
there'll be absolutely no way to use the class. We want to
prevent direct instantiation, but we still need to allow a
way to get a reference to an instance of the singleton object.
| Is This Answer Correct ? | 3 Yes | 2 No |
Post New Answer View All Answers
What is the use of hashcode in java ?
What is the Spring2.5 MVC Navigation flow?
What are the main classes of the list interfaces? : java collections
What are the interfaces in java collections? : java collections
Which server-side script takes the input from JavaScript, can access the database if it needs to, and processes the data.
What is the enumerator of the java collection framework? : java collections
what is mean by hasing and maping in java platform and advantage?
What are the types of the main implementing classes in the map interfaces? : java collections
What are the different types of ways where you can iterate over a list? : java collections
Hi Friends , am newbie to ajax. For example just consider one account registration - A form contains 8 text fields with submit button. In this form second texbox contains "username " . On right side of text box there is a label box . On clilck action i need to determine user is available or not. Is it possible on clicking label or should i click submit button.
can u draw class/object diagram for ATM
What are the different types of features of the java collections framework? : java collections
What is java collection? : java collections
How do I find jre path in windows?
What is the use of the list interface in the java collection? : java collections