Java Singleton Pattern


Problem Statement :


"The singleton pattern is a design pattern that restricts the instantiation of a class to one object. This is useful when exactly one object is needed to coordinate actions across the system."
- Wikipedia: Singleton Pattern

Complete the Singleton class in your editor which contains the following components:

1.A private Singleton non parameterized constructor.
2.A public String instance variable named str.
3.Write a static method named getSingleInstance that returns the single instance of the Singleton class.
Once submitted, our hidden Solution class will check your code by taking a String as input and then using your Singleton class to print a line.

Input Format

You will not be handling any input in this challenge.

Output Format

You will not be producing any output in this challenge.


Solution :



title-img 


                            Solution in C :

import java.io.*;
import java.util.*;
import java.text.*;
import java.math.*;
import java.util.regex.*;
import java.lang.reflect.*;

class Singleton {
    private static Singleton instance;
    public static String str;
    private Singleton() {}

    static Singleton getSingleInstance() {
        if (instance == null) {
            instance = new Singleton();
        }
        return instance;
    }
}








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