How to implement a singleton pattern?

Create a public class having a private constructor. Private constructor ensures that the object cannot be created outside of the class.

Create a private static variable of the type Class itself.

Create a public static method e.g. getInstance() that returns the reference of the static variable, if the static variable is null then create a object for the class.

package org.javatutorials.designpatterns;

//Step 1
public class SingletonPattern {

	//Step 2
	private static SingletonPattern mySingletonObj;

	private SingletonPattern() {

	}

	public static SingletonPattern getInstance() {

		if (mySingletonObj == null) {
			mySingletonObj = new SingletonPattern();

		}

		return mySingletonObj;
	}
}

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