Python: Bridge Pattern

 

DuBridge.py

# 桥接模式  Bridge Pattern
# DuBridyge.py editor: geovindu, Geovin Du

from __future__ import annotations
from abc import ABC, abstractmethod


class Abstraction:
    """
    The Abstraction defines the interface for the "control" part of the two
    class hierarchies. It maintains a reference to an object of the
    Implementation hierarchy and delegates all of the real work to this object.
    """

    def __init__(self, implementation: Implementation) -> None:
        self.implementation = implementation

    def operation(self) -> str:
        return (f"抽象:用的基本运算:\n"
                f"{self.implementation.operation_implementation()}")


class ExtendedAbstraction(Abstraction):
    """
    You can extend the Abstraction without changing the Implementation classes.
    """

    def operation(self) -> str:
        return (f"扩展抽象:使用的扩展操作:\n"
                f"{self.implementation.operation_implementation()}")


class Implementation(ABC):
    """
    The Implementation defines the interface for all implementation classes. It
    doesn't have to match the Abstraction's interface. In fact, the two
    interfaces can be entirely different. Typically the Implementation interface
    provides only primitive operations, while the Abstraction defines higher-
    level operations based on those primitives.
    """

    @abstractmethod
    def operation_implementation(self) -> str:
        pass


"""
Each Concrete Implementation corresponds to a specific platform and implements
the Implementation interface using that platform's API.
"""


class ConcreteImplementationA(Implementation):
    def operation_implementation(self) -> str:
        return "具体实现Gevoin Du:这是在平台Geovin Du上的结果."


class ConcreteImplementationB(Implementation):
    def operation_implementation(self) -> str:
        return "具体实施涂聚文:这是在涂聚文平台上的结果."


def client_code(abstraction: Abstraction) -> None:
    """
    Except for the initialization phase, where an Abstraction object gets linked
    with a specific Implementation object, the client code should only depend on
    the Abstraction class. This way the client code can support any abstraction-
    implementation combination.
    """

    # ...

    print(abstraction.operation(), end="")

　　

main.py:

调用：

        ## 桥接模式  Bridge Pattern
        implementation = DuBridge.ConcreteImplementationA()
        abstraction = DuBridge.Abstraction(implementation)
        DuBridge.client_code(abstraction)

        print("\n")

        implementation = DuBridge.ConcreteImplementationB()
        abstraction = DuBridge.ExtendedAbstraction(implementation)
        DuBridge.client_code(abstraction)

　　

 

输出：

抽象:用的基本运算:
具体实现Gevoin Du:这是在平台Geovin Du上的结果.

扩展抽象:使用的扩展操作:
具体实施涂聚文:这是在涂聚文平台上的结果.