外观模式

Intent

• Provide a unified interface to a set of interfaces in a subsystem. Facade defines a higher-level interface that makes the subsystem easier to use.
• Wrap a complicated subsystem with a simpler interface.

Structure

facade by keith

代码:

public class Facade {
    public static void main(String[] args) {
        Customer customer = new Customer("king");
        ServerFacade facade = new ServerFacade(new Server());
        facade.doServer(customer);
    }
}
class ServerFacade {
    Server server;

    public ServerFacade(Server server) {
        this.server = server;
    }

    public void doServer(Customer customer) {
        server.doCheck(customer);
        server.doService(customer);
        server.afterService(customer);
    }
}
class Customer {
    String name;

    public Customer(String name) {
        this.name = name;
    }
}
class Server {
    public void doCheck(Customer customer) {
        System.out.println(customer.name + " is checking");
    }

    public void doService(Customer customer) {
        System.out.println(customer.name + " is on service");
    }

    public void afterService(Customer customer) {
        System.out.println(customer.name + " is done server");
    }
}

3. Output

king is checking
king is on service
king is done server

Refenrence

1. Design Patterns
2. 设计模式