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Notes.md
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  1. Software Design
  2. Design Patterns
  3. Creational Design Pattern

Singleton DP

  • Creational Design Pattern

  • Only one instance of the class should exist

Example : Eager Initialization

public class Singleton {

    private static Singleton instance = new Singleton();

    private Singleton() {
    }

    public static Singleton getObject() {
        return instance;
    }

}

Example : Lazy initialization

public class Singleton {

    private static Singleton instance = null;
    
    private Singleton() {}
    
    public static Singleton getObject(){ 
        if(instance == null) { 
            instance = new Singleton();  
        }  
        return instance;  
    } 

}
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Last updated 2 years ago

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