Bridge Pattern
Description:
» The Bridge pattern allows for development of an interface and implementation of a component to proceed independently;» The Bridge pattern decouples an abstraction from its implementation, enabling them to vary independently;
» The Bridge pattern is useful when a new version of software is brought out that will replace an existing version, but the older version must still run for its existing client base;
» The Abstraction component is what is commonly called a Portal.
Use When:
» Want to completely hide implementations from clients;» Want to avoid binding an implementation to an abstraction directly;
» Want to change an implementation without even recompiling an abstraction;
» Want to combine different parts of a system at runtime.
public class PrinterBridge
{
//Define the Pattern Interface and Handler Objects.
//Define the IPrinter interface to be used as the "blueprint" for the main Bridge classes.
public interface IPrinter
{
string PrintTestPage();
}
//Each Bridge class (object) will contain a different implementation of the required methods.
public class InkJetPrinter : IPrinter
{
public string PrintTestPage()
{
return ("This text has been printed on a Ink Jet Printer");
}
}
public class LaserPrinter : IPrinter
{
public string PrintTestPage()
{
return ("This text has been printed on a Laser Jet Printer");
}
}
public class DotMatrixPrinter : IPrinter
{
public string PrintTestPage()
{
return ("This text has been printed on a Dot Matrix Printer");
}
}
}
{
//Define the Pattern Interface and Handler Objects.
//Define the IPrinter interface to be used as the "blueprint" for the main Bridge classes.
public interface IPrinter
{
string PrintTestPage();
}
//Each Bridge class (object) will contain a different implementation of the required methods.
public class InkJetPrinter : IPrinter
{
public string PrintTestPage()
{
return ("This text has been printed on a Ink Jet Printer");
}
}
public class LaserPrinter : IPrinter
{
public string PrintTestPage()
{
return ("This text has been printed on a Laser Jet Printer");
}
}
public class DotMatrixPrinter : IPrinter
{
public string PrintTestPage()
{
return ("This text has been printed on a Dot Matrix Printer");
}
}
}
public class PrinterBridge
{
//Define the Pattern Interface and Handler Objects.
//Define the IPrinter interface to be used as the "blueprint" for the main Bridge classes.
public interface IPrinter
{
string PrintTestPage();
}
//Each Bridge class (object) will contain a different implementation of the required methods.
public class InkJetPrinter : IPrinter
{
public string PrintTestPage()
{
return ("This text has been printed on a Ink Jet Printer");
}
}
public class LaserPrinter : IPrinter
{
public string PrintTestPage()
{
return ("This text has been printed on a Laser Jet Printer");
}
}
public class DotMatrixPrinter : IPrinter
{
public string PrintTestPage()
{
return ("This text has been printed on a Dot Matrix Printer");
}
}
}
{
//Define the Pattern Interface and Handler Objects.
//Define the IPrinter interface to be used as the "blueprint" for the main Bridge classes.
public interface IPrinter
{
string PrintTestPage();
}
//Each Bridge class (object) will contain a different implementation of the required methods.
public class InkJetPrinter : IPrinter
{
public string PrintTestPage()
{
return ("This text has been printed on a Ink Jet Printer");
}
}
public class LaserPrinter : IPrinter
{
public string PrintTestPage()
{
return ("This text has been printed on a Laser Jet Printer");
}
}
public class DotMatrixPrinter : IPrinter
{
public string PrintTestPage()
{
return ("This text has been printed on a Dot Matrix Printer");
}
}
}