Which .Gang of Four. design pattern is shown below?

C# Interview Questions and Answers

(Continued from previous question...)

21. Which .Gang of Four. design pattern is shown below?

    public class A {

        private A instance;

        private A() {

        }

        public
    static A Instance {

            get

            {

                if ( A == null )

                    A = new A();

                return instance;

            }

        }

    }

1. Factory
2. Abstract Factory
3. Singleton
4. Builder

(Continued on next question...)

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