Adapter -- Design Pattern

       Convert the interface of a class into another interface clients expect. Adapter lets classes work together that couldn't otherwise because of incompatible interfaces. 

Participants

      The classes and/or objects participating in this pattern are:

• Target(Chemical Compound) : Defines the domain-specific interface that Client uses.

• Adapter(Compound) :Adapts the interface Adaptee to the Target interface.

• Adaptee(Chemical Data bank): Defines an existing interface that needs adapting.

• Client(Adapter App): Collaborates with objects conforming to the Target interface.

Sample code:

// Adapter pattern -- Structural example

using System;       namespace Adapter.Structural {      /// <summary>      /// MainApp startup class for Structural     /// Adapter Design Pattern.    /// </summary>    class MainApp    {     /// <summary>     /// Entry point into console application.     /// </summary>     static void Main()     {       // Create adapter and place a request       Target target = new Adapter();       target.Request();       // Wait for user       Console.ReadKey();     }     }    /// <summary>    /// The 'Target' class    /// </summary>    class Target    {     public virtual void Request()     {       Console.WriteLine("Called Target Request()");      }    }    /// <summary>    /// The 'Adapter' class    /// </summary>    class Adapter : Target    {         private Adaptee _adaptee = new Adaptee();        public override void Request()        {       // Possibly do some other work       //  and then call SpecificRequest       _adaptee.SpecificRequest();       }     }      /// <summary>      /// The 'Adaptee' class     /// </summary>     class Adaptee     {      public void SpecificRequest()      {       Console.WriteLine("Called SpecificRequest()");     }     } }

Output     Called SpecificRequest()