
Before Writing Singleton Design pattern you should follow these steps.
#1). create an instance as static and return type as The same class, and it should be assigned as null.
private
static
Singletonn instance =
null
;
#2). "Create a Constructor as private" to deny the creation of object from other class.
private
Singletonn(){
}
public
static
Singletonn getInstance(){
}
#4). At last return the class Object.
Here We are creating the object once only not again and again.The first time created object is returning again when you called.
package
javabynataraj.basic;
class
Singletonn {
private
static
Singletonn instance =
null
;
private
Singletonn(){
}
public
static
Singletonn getInstance(){
if
(instance==
null
){
instance =
new
Singletonn();
}
return
instance;
}
}
public
class
Singleton{
public
static
void
main(String[] args) {
System.out.println(
"before calling ..."
);
System.out.println(Singletonn.getInstance());
System.out.println(
"Once Called"
);
System.out.println(Singletonn.getInstance());
System.out.println(
"Second time called"
);
}
}
Very informative and worthy post. Thanks for the sharing such a precious updates with us.
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