Design mode-Bridging mode (bridge pattern)

Design mode of bridge pattern structure

Defined:

1. Separate the abstract and implementation sections so that they run independently.
2. Avoid using inheritance to cause the number of system classes to burst, consider bridging mode.
3. Bridging mode translates inheritance relationships into associations, reduces coupling, and reduces the amount of code.

For example:

 Public Interface Shape {    publicvoid  bepaint (String color);}

 Public Abstract class Color {    shape shape;      Public void setshape (Shape shape) {        this. Shape = shape;    }       Public Abstract void draw ();}

 Public class extends Color {    @Override    publicvoid  Draw () {        shape.bepaint ("Red");}    } 

 Public class extends Color {    @Override    publicvoid  Draw () {        shape.bepaint (" Green ");}    }

 Public class Implements shape {    @Override    The circle of the publicvoid  bepaint (        String color) {+ ");    }}

 Public class Implements Shape {    @Override    publicvoid  bepaint (String color) {        + " Square ");}    }

 Public classTest {/**     * @paramargs*/     Public Static voidMain (string[] args) {Shape circle_shape=NewCircle (); Color Red_color=NewRed ();        Red_color.setshape (Circle_shape);        Red_color.draw (); System.out.println ("-----------------"); Shape Square_shape=NewSquare ();        Red_color.setshape (Square_shape);    Red_color.draw (); }}

Experimental results:

Red circle ----------------- Red Square

Bridge mode pros and Cons: Cons:

Design difficulty is relatively large, to be able to correctly identify the system of independent changes in the dimensions, has limitations.

Advantages:

1. It is better to realize the decoupling of the abstract part and the realization part than the implementation scheme of the inheritance;
2. Expandable without modification of the original system;

Design mode-Bridging mode (bridge pattern)