1. OCP-开放封闭原则

面向扩展开放，面向修改封闭。关键点是抽象。

2. | SRP |

单一职责原则

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Single Responsibility Principle

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| OCP |

开放封闭原则

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Open Closed Principle

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| LSP |

里氏替换原则

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Liskov Substitution Principle

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ISP

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接口分离原则

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Interface Segregation Principle

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| DIP |

依赖倒置原则

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Dependency Inversion Principle

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| LKP |

最少知识原则

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Least Knowledge Principle

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