Delegation Pattern and The By Keyword

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Delegation Pattern and The By Keyword
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• The delegation pattern is a technique where an
  object expresses a certain behavior to the
  outside but simultaneously delegates
  responsibility for implementing that behavior to
  an associated object.Let's understand this with
  the help of an exampleLet's say we want a
  printer. And a printer does what it is supposed
  to do. Let's create an interface to show this
  behavior.
• interface Printer
• void print(final String message)
• https//erpsolutions.oodles.io/developer-blogs/Del
  egation-Pattern-and-The-By-Keyword/

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• Now it does not matter which printer prints this.
• So let's say we have Three Printers(Canon, Epson,
  and HP) . Whichever printer is available or has
  ink prints the text. Now all of them are of type
  printers so all three will implement the Printer
  interface.
• class CanonPrinter implements Printer
• _at_Override
• public void print(String message)
• System.out.println("Canon Printer "message )
• class EpsonPrinter implements Printer
• _at_Override
• public void print(String message)
• System.out.println("Epson Printer
  "message)