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bridge-pattern/README.md

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+# bridge-pattern
+Project of eample of bridge pattern implement by Java. 
+
+## What is bridge pattern
+decouple an abstraction from its implementation so that the two can vary independently
+
+class diagram:
+
+![bridge pattern](https://github.com/kan01234/design-patterns/blob/master/bridge-pattern/bridge-pattern.png)
+
+- Implementation interface to define implmentation needed
+- ConcreteImplementation implement methods in Implementation interface
+- Abstraction define function will use
+- ConcreteAbstraction can custom other functions, and use implmentation from ConreteImplementation
+
+## When to use bridge pattern
+- want to decoupleing abstraction, implementation
+- want abstraction, implementation can change independently
+
+## Example
+Assume we have a PS4 controller, and the controller can use for PS4 and steam console.
+
+class diagram:
+
+![bridge pattern example](https://github.com/kan01234/design-patterns/blob/master/bridge-pattern/bridge-pattern-example.png)
+
+- Controller is the Abstraction
+- PS4Controller is the ConcreteAbstraction
+- ControllerFunction is the Implementation
+- PS4Function, SteamFunction is the ConcreteImplementation
+
+just replace the ControllerFunction when create PS4Controller, and it can use for difference consoles.
+```java
+public void ControllerTest() {
+    Controller ps4ControllerWithPS4 = new PS4Controller(new PS4Function());
+    Controller ps4ControllerWithSteam = new PS4Controller(new SteamFunction());
+    System.out.println("move joystick up");
+    ps4ControllerWithPS4.joystickMove("up");
+    ps4ControllerWithSteam.joystickMove("up");
+    System.out.println("press ps button");
+    ps4ControllerWithPS4.pressHome();
+    ps4ControllerWithSteam.pressHome();
+}
+```
+
+and the output like
+```
+move joystick up
+move up
+pressed up
+press ps button
+show PS4 home menu
+unsupported button
+```