Design Patterns | Adapter

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1. References
2. Example
   • The Adaptee
   • The Adapter
   • A simple class to test the Adapter design pattern

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1. References
   • Definition: (source: http://en.wikipedia.org/wiki/Adapter_pattern)
     
     An adapter helps two incompatible interfaces to work together.
     
     
   • Class diagram: (source: http://en.wikipedia.org/wiki/Adapter_pattern)
     
     
2. Example
   • The Adaptee:
     
     public class CustomOperation { public int customAdd(final String a, final String b) { return Integer.valueOf(a) + Integer.valueOf(b); } }
     
   • The Adapter:
     
     public class Operation { private CustomOperation adaptee; Operation(final CustomOperation adaptee) { this.adaptee = adaptee; } public int add(final int a, final int b) { return adaptee.customAdd(String.valueOf(a), String.valueOf(b)); } }
     
   • A simple class to test the Adapter design pattern:
     
     public class AdapterPatternTest { public static void main(String[] args) { final CustomOperation adaptee = new CustomOperation(); final Operation adapter = new Operation(adaptee); System.out.println(adapter.add(2, 3)); } }