Singleton snippet (Java)

public class singleton {    	private static singleton obj;    	  	private singleton(){  		System.out.println("Constructor is called only once.");  	}  	  	public static singleton getInstance(){  		if(obj == null){  			obj = new singleton();  		}  		return obj;  	}    	  	public int add(int i, int j){  		return (i + j);  	}  	  	public int sub(int i, int j){  		return (i-j);  	}  	  	public static void main( String [] args){  		  		singleton obj1 = singleton.getInstance();		  		singleton obj2 = singleton.getInstance();  		singleton.getInstance();  		singleton.getInstance();  		singleton.getInstance();  		  		// 'n' number of object creation won't call constructor 'n' times. This is singleton feature.  		  		System.out.println(singleton.getInstance().add(5, 6));	//it is object.function() call  		  	}  	  }

Output:

Constructor is called only once.
11

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