Review - Design Patterns: Elements of Reusable Object-Oriented Software

Design Patterns: Elements of Reusable Object-Oriented SoftwareDesign Patterns: Elements of Reusable Object-Oriented Software by Erich Gamma
My rating: 5 of 5 stars

Depending on on how you think of programming, this book could be incredibly insightful, or horribly abstract and impractical. Since I prefer and tend to think in patterns and abstractions, I found this book close to my heart. It uses a variety of languages for examples, so a willingness to explore concepts, not practical solutions, is essential.

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Salient Chacteristic(s)
A private keyed list for tracking objectsA private constructorNamed objectsCode

using System.Collections.Generic;
using System.Linq;

namespace DesignPatterns
{
    public class Multiton
    {
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        private static IDictionary<int, Multiton> _Tracker = new Dictionary<int, Multiton> { };

        private Multiton()
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        public static Multiton GetInstance(int key)
        {
            //value to return
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            lock (_Tracker)
            { 
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                if(!_Tracker.TryGetValue(key, out item))
                {
                    item = new Multiton();

                    //calculate next key
       …
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This linked file contains the original code in C#, as well as the same code converted to VB.NET.

Salient Characteristic(s)
Sets an internal pointer to the decorated object, sending method calls and property actions to the internal objectExtends the object by wrapping it and adding some aspect handled by the decorator
Code

using System;
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