\u5927\u767d\u8bdd\u7406\u89e3<\/strong>\uff1a\u8bbe\u8ba1\u6a21\u5f0f\u662f\u524d\u4eba\u603b\u7ed3\u7684\u4e00\u5957\u7ecf\u9a8c\u3002\u6309\u7167\u524d\u4eba\u603b\u7ed3\u7684\u7ecf\u9a8c\u53bb\u8bbe\u8ba1\u67b6\u6784\u3001\u7f16\u5199\u4ee3\u7801\uff0c\u6709\u5f88\u591a\u597d\u5904\uff1a<\/p>\n\n\n\n \u8bbe\u8ba1\u6a21\u5f0f\u6700\u65e9\u5e76\u975e\u6765\u81ea\u8f6f\u4ef6\u9886\u57df\uff0c\u800c\u662f\u6765\u81ea\u5efa\u7b51\u9886\u57df<\/strong>\uff1a<\/p>\n\n\n\n GoF\u8bbe\u8ba1\u6a21\u5f0f\u5171\u670923\u79cd<\/strong>\uff0c\u6839\u636e\u7528\u9014\u5206\u4e3a\u4e09\u5927\u7c7b\uff1a<\/p>\n\n\n\n \u521b\u5efa\u578b\u6a21\u5f0f\uff085\u79cd\uff09<\/p>\n\n\n\n \u6838\u5fc3\u4f5c\u7528<\/strong>\uff1a\u63d0\u4f9b\u521b\u5efa\u5bf9\u8c61\u7684\u673a\u5236\uff0c\u63d0\u5347\u4ee3\u7801\u7684\u7075\u6d3b\u6027\u548c\u53ef\u590d\u7528\u6027\u3002<\/p>\n\n\n\n \u7ed3\u6784\u578b\u6a21\u5f0f\uff087\u79cd\uff09<\/p>\n\n\n\n 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\u4e3a\u4ec0\u4e48\u5b66\u4e60\u8bbe\u8ba1\u6a21\u5f0f<\/h3>\n\n\n\n
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\n
\u8bbe\u8ba1\u6a21\u5f0f\u7684\u5206\u7c7b<\/h3>\n\n\n\n
\u6a21\u5f0f<\/th> \u82f1\u6587\u540d<\/th> \u4e00\u53e5\u8bdd\u63cf\u8ff0<\/th><\/tr><\/thead> \u5355\u4f8b\u6a21\u5f0f<\/td> Singleton<\/td> \u4fdd\u8bc1\u4e00\u4e2a\u7c7b\u53ea\u6709\u4e00\u4e2a\u5b9e\u4f8b<\/td><\/tr> \u5de5\u5382\u65b9\u6cd5\u6a21\u5f0f<\/td> Factory Method<\/td> \u5b9a\u4e49\u521b\u5efa\u5bf9\u8c61\u7684\u63a5\u53e3\uff0c\u8ba9\u5b50\u7c7b\u51b3\u5b9a\u5b9e\u4f8b\u5316\u54ea\u4e2a\u7c7b<\/td><\/tr> \u62bd\u8c61\u5de5\u5382\u6a21\u5f0f<\/td> Abstract Factory<\/td> \u521b\u5efa\u76f8\u5173\u6216\u4f9d\u8d56\u5bf9\u8c61\u7684\u5bb6\u65cf\uff0c\u800c\u65e0\u9700\u660e\u786e\u6307\u5b9a\u5177\u4f53\u7c7b<\/td><\/tr> \u5efa\u9020\u8005\u6a21\u5f0f<\/td> Builder<\/td> \u5206\u6b65\u9aa4\u521b\u5efa\u590d\u6742\u5bf9\u8c61<\/td><\/tr> \u539f\u578b\u6a21\u5f0f<\/td> Prototype<\/td> \u901a\u8fc7\u590d\u5236\u73b0\u6709\u5bf9\u8c61\u6765\u521b\u5efa\u65b0\u5bf9\u8c61<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n \u6a21\u5f0f<\/th> \u82f1\u6587\u540d<\/th> \u4e00\u53e5\u8bdd\u63cf\u8ff0<\/th><\/tr><\/thead> \u4ee3\u7406\u6a21\u5f0f<\/td> Proxy<\/td> \u4e3a\u5176\u4ed6\u5bf9\u8c61\u63d0\u4f9b\u4e00\u79cd\u4ee3\u7406\u4ee5\u63a7\u5236\u5bf9\u8fd9\u4e2a\u5bf9\u8c61\u7684\u8bbf\u95ee<\/td><\/tr> \u88c5\u9970\u5668\u6a21\u5f0f<\/td> Decorator<\/td> \u52a8\u6001\u5730\u7ed9\u5bf9\u8c61\u6dfb\u52a0\u989d\u5916\u7684\u804c\u8d23<\/td><\/tr> \u9002\u914d\u5668\u6a21\u5f0f<\/td> Adapter<\/td> \u5c06\u4e00\u4e2a\u7c7b\u7684\u63a5\u53e3\u8f6c\u6362\u6210\u5ba2\u6237\u5e0c\u671b\u7684\u53e6\u4e00\u4e2a\u63a5\u53e3<\/td><\/tr> \u6865\u63a5\u6a21\u5f0f<\/td> Bridge<\/td> \u5c06\u62bd\u8c61\u90e8\u5206\u4e0e\u5b9e\u73b0\u90e8\u5206\u5206\u79bb\uff0c\u4f7f\u5b83\u4eec\u90fd\u53ef\u4ee5\u72ec\u7acb\u53d8\u5316<\/td><\/tr> \u5916\u89c2\u6a21\u5f0f<\/td> Facade<\/td> \u4e3a\u5b50\u7cfb\u7edf\u4e2d\u7684\u4e00\u7ec4\u63a5\u53e3\u63d0\u4f9b\u4e00\u4e2a\u7edf\u4e00\u7684\u5165\u53e3<\/td><\/tr> \u7ec4\u5408\u6a21\u5f0f<\/td> Composite<\/td> \u5c06\u5bf9\u8c61\u7ec4\u5408\u6210\u6811\u5f62\u7ed3\u6784\u4ee5\u8868\u793a”\u90e8\u5206-\u6574\u4f53”\u7684\u5c42\u6b21\u7ed3\u6784<\/td><\/tr> \u4eab\u5143\u6a21\u5f0f<\/td> Flyweight<\/td> \u8fd0\u7528\u5171\u4eab\u6280\u672f\u6709\u6548\u5730\u652f\u6301\u5927\u91cf\u7ec6\u7c92\u5ea6\u7684\u5bf9\u8c61<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n \u6a21\u5f0f<\/th> \u82f1\u6587\u540d<\/th> \u4e00\u53e5\u8bdd\u63cf\u8ff0<\/th><\/tr><\/thead> \u89c2\u5bdf\u8005\u6a21\u5f0f<\/td> Observer<\/td> \u5b9a\u4e49\u5bf9\u8c61\u95f4\u7684\u4e00\u5bf9\u591a\u4f9d\u8d56\uff0c\u5f53\u4e00\u4e2a\u5bf9\u8c61\u6539\u53d8\u65f6\uff0c\u6240\u6709\u4f9d\u8d56\u8005\u90fd\u4f1a\u6536\u5230\u901a\u77e5<\/td><\/tr> \u7b56\u7565\u6a21\u5f0f<\/td> Strategy<\/td> \u5b9a\u4e49\u7b97\u6cd5\u65cf\uff0c\u5206\u522b\u5c01\u88c5\u8d77\u6765\uff0c\u8ba9\u5b83\u4eec\u53ef\u4ee5\u4e92\u76f8\u66ff\u6362<\/td><\/tr> \u6a21\u677f\u65b9\u6cd5\u6a21\u5f0f<\/td> Template Method<\/td> \u5b9a\u4e49\u7b97\u6cd5\u9aa8\u67b6\uff0c\u5c06\u67d0\u4e9b\u6b65\u9aa4\u5ef6\u8fdf\u5230\u5b50\u7c7b\u4e2d\u5b9e\u73b0<\/td><\/tr> \u8d23\u4efb\u94fe\u6a21\u5f0f<\/td> Chain of Responsibility<\/td> \u4e3a\u8bf7\u6c42\u521b\u5efa\u4e00\u6761\u63a5\u6536\u8005\u94fe\uff0c\u6cbf\u94fe\u4f20\u9012\u8bf7\u6c42\u76f4\u5230\u88ab\u5904\u7406<\/td><\/tr> \u8fed\u4ee3\u5668\u6a21\u5f0f<\/td> Iterator<\/td> \u63d0\u4f9b\u4e00\u79cd\u65b9\u6cd5\u987a\u5e8f\u8bbf\u95ee\u805a\u5408\u5bf9\u8c61\u4e2d\u7684\u5404\u4e2a\u5143\u7d20<\/td><\/tr> \u72b6\u6001\u6a21\u5f0f<\/td> State<\/td> \u5141\u8bb8\u5bf9\u8c61\u5728\u5185\u90e8\u72b6\u6001\u6539\u53d8\u65f6\u6539\u53d8\u5b83\u7684\u884c\u4e3a<\/td><\/tr> \u547d\u4ee4\u6a21\u5f0f<\/td> Command<\/td> \u5c06\u8bf7\u6c42\u5c01\u88c5\u4e3a\u5bf9\u8c61\uff0c\u4ee5\u4fbf\u7528\u4e0d\u540c\u8bf7\u6c42\u6765\u53c2\u6570\u5316\u5176\u4ed6\u5bf9\u8c61<\/td><\/tr> \u5907\u5fd8\u5f55\u6a21\u5f0f<\/td> Memento<\/td> \u5728\u4e0d\u7834\u574f\u5c01\u88c5\u6027\u7684\u524d\u63d0\u4e0b\uff0c\u6355\u83b7\u5bf9\u8c61\u7684\u5185\u90e8\u72b6\u6001<\/td><\/tr> \u8bbf\u95ee\u8005\u6a21\u5f0f<\/td> Visitor<\/td> \u8868\u793a\u4e00\u4e2a\u4f5c\u7528\u4e8e\u67d0\u5bf9\u8c61\u7ed3\u6784\u4e2d\u7684\u5404\u5143\u7d20\u7684\u64cd\u4f5c<\/td><\/tr> \u4e2d\u4ecb\u8005\u6a21\u5f0f<\/td> Mediator<\/td> \u7528\u4e00\u4e2a\u4e2d\u4ecb\u5bf9\u8c61\u6765\u5c01\u88c5\u4e00\u7cfb\u5217\u7684\u5bf9\u8c61\u4ea4\u4e92<\/td><\/tr> \u89e3\u91ca\u5668\u6a21\u5f0f<\/td> Interpreter<\/td> \u7ed9\u5b9a\u4e00\u4e2a\u8bed\u8a00\uff0c\u5b9a\u4e49\u5b83\u7684\u6587\u6cd5\u8868\u793a\uff0c\u5e76\u5b9a\u4e49\u4e00\u4e2a\u89e3\u91ca\u5668<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n \u8bbe\u8ba1\u6a21\u5f0f\u539f\u5219\uff08SOLID\uff09<\/h2>\n\n\n\n
\u539f\u5219<\/th> \u82f1\u6587\u5168\u79f0<\/th> \u7f29\u5199<\/th> \u6838\u5fc3\u601d\u60f3<\/th><\/tr><\/thead> \u5355\u4e00\u804c\u8d23\u539f\u5219<\/td> Single Responsibility Principle<\/td> S<\/td> \u4e00\u4e2a\u7c7b\u53ea\u8d1f\u8d23\u4e00\u4e2a\u529f\u80fd\u6a21\u5757<\/td><\/tr> \u5f00\u653e\u5c01\u95ed\u539f\u5219<\/td> Open Close Principle<\/td> O<\/td> \u5bf9\u6269\u5c55\u5f00\u653e\uff0c\u5bf9\u4fee\u6539\u5c01\u95ed<\/td><\/tr> \u91cc\u6c0f\u66ff\u6362\u539f\u5219<\/td> Liskov Substitution Principle<\/td> L<\/td> \u5b50\u7c7b\u5fc5\u987b\u80fd\u591f\u66ff\u6362\u7236\u7c7b<\/td><\/tr> \u63a5\u53e3\u9694\u79bb\u539f\u5219<\/td> Interface Segregation Principle<\/td> I<\/td> \u5ba2\u6237\u7aef\u4e0d\u5e94\u4f9d\u8d56\u5b83\u4e0d\u9700\u8981\u7684\u63a5\u53e3<\/td><\/tr> \u4f9d\u8d56\u5012\u7f6e\u539f\u5219<\/td> Dependency Inversion Principle<\/td> D<\/td> \u4f9d\u8d56\u62bd\u8c61\uff0c\u800c\u975e\u5177\u4f53\u5b9e\u73b0<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n \n
\u5355\u4e00\u804c\u8d23\u539f\u5219\uff08SRP\uff09<\/h3>\n\n\n\n
\n
Employee<\/code>\u7c7b\uff0c\u5305\u542b\u4ee5\u4e0b\u529f\u80fd\uff1a<\/p>\n\n\n\n\n
![\"\u8fdd\u53cd\u5355\u4e00\u804c\u8d23\"\/](\"http:\/\/118.25.99.91\/image\/DesignPattern\/image-20230227145935832.png\")
<\/div>\/\/ \u96c7\u5458\u7c7b - \u53ea\u8d1f\u8d23\u96c7\u5458\u4fe1\u606f\u7ba1\u7406\npublic class Employee {\n private String id;\n private String name;\n private double salary;\n \n \/\/ \u96c7\u5458\u76f8\u5173\u7684\u6838\u5fc3\u4e1a\u52a1\u903b\u8f91\n public void calculateSalary() { \/* ... *\/ }\n public void updateInfo() { \/* ... *\/ }\n}\n\n\/\/ \u6253\u5370\u7c7b - \u53ea\u8d1f\u8d23\u6253\u5370\u529f\u80fd\npublic class EmployeePrinter {\n private Employee employee;\n \n public EmployeePrinter(Employee employee) {\n this.employee = employee;\n }\n \n public void printBasicInfo() { \/* ... *\/ }\n public void printDetailedReport() { \/* ... *\/ }\n}<\/code><\/pre>\n\n\n\n![\"\u9075\u5faa\u5355\u4e00\u804c\u8d23\"\/](\"http:\/\/118.25.99.91\/image\/DesignPattern\/image-20230227150423502.png\")
<\/div>\n
\u5f00\u653e\u5c01\u95ed\u539f\u5219\uff08OCP\uff09<\/h3>\n\n\n\n
\n
\n
\/\/ \u62bd\u8c61\u63a5\u53e3 - \u5b9a\u4e49\u7ed3\u6784\npublic interface Connection {\n Statement createStatement();\n PreparedStatement prepareStatement(String sql);\n \/\/ ...\n}\n\n\/\/ \u5177\u4f53\u5b9e\u73b01 - MySQL\npublic class MySQLConnection implements Connection {\n @Override\n public Statement createStatement() {\n return new MySQLStatement();\n }\n \/\/ ...\n}\n\n\/\/ \u5177\u4f53\u5b9e\u73b02 - Oracle\npublic class OracleConnection implements Connection {\n @Override\n public Statement createStatement() {\n return new OracleStatement();\n }\n \/\/ ...\n}\n\n\/\/ \u4f7f\u7528\u65b9 - \u4f9d\u8d56\u62bd\u8c61\npublic class UserDao {\n private Connection connection;\n \n public UserDao(Connection connection) {\n this.connection = connection; \/\/ \u53ef\u4ee5\u4f20\u5165MySQL\u6216Oracle\n }\n \n \/\/ \u65e0\u9700\u4fee\u6539UserDao\uff0c\u5373\u53ef\u652f\u6301\u65b0\u7684\u6570\u636e\u5e93\n}<\/code><\/pre>\n\n\n\n![\"\u5f00\u653e\u5c01\u95ed\u539f\u5219\"\/](\"http:\/\/118.25.99.91\/image\/DesignPattern\/image-20230227155416973.png\")
<\/div>\n
\u91cc\u6c0f\u66ff\u6362\u539f\u5219\uff08LSP\uff09<\/h3>\n\n\n\n
\n
\n
\/\/ \u7236\u7c7b\uff1a\u77e9\u5f62\npublic class Rectangle {\n protected int width;\n protected int height;\n \n public void setWidth(int width) { this.width = width; }\n public void setHeight(int height) { this.height = height; }\n public int getArea() { return width * height; }\n}\n\n\/\/ \u5b50\u7c7b\uff1a\u6b63\u65b9\u5f62\uff08\u8fdd\u53cdLSP\uff09\npublic class Square extends Rectangle {\n @Override\n public void setWidth(int width) {\n this.width = width;\n this.height = width; \/\/ \u5f3a\u5236\u76f8\u7b49\n }\n \n @Override\n public void setHeight(int height) {\n this.width = height; \/\/ \u5f3a\u5236\u76f8\u7b49\n this.height = height;\n }\n}\n\n\/\/ \u6d4b\u8bd5\npublic void testRectangle(Rectangle rect) {\n rect.setWidth(5);\n rect.setHeight(4);\n \/\/ \u671f\u671b\u9762\u79ef = 20\uff0c\u4f46Square\u5b9e\u9645\u8fd4\u56de = 16\n assert rect.getArea() == 20 : \"\u9762\u79ef\u8ba1\u7b97\u9519\u8bef\uff01\";\n}<\/code><\/pre>\n\n\n\n\/\/ \u62bd\u8c61\u7236\u7c7b\npublic abstract class Shape {\n public abstract int getArea();\n}\n\npublic class Rectangle extends Shape {\n private int width;\n private int height;\n \/\/ ... \u6b63\u5e38\u5b9e\u73b0\n}\n\npublic class Square extends Shape {\n private int side;\n \/\/ ... \u72ec\u7acb\u5b9e\u73b0\uff0c\u4e0d\u7ee7\u627fRectangle\n}<\/code><\/pre>\n\n\n\n![\"\u91cc\u6c0f\u66ff\u6362\u539f\u5219\"\/](\"http:\/\/118.25.99.91\/image\/DesignPattern\/image-20230227164630136.png\")
<\/div>![\"\u91cc\u6c0f\u66ff\u6362\u539f\u5219\u6539\u8fdb\"\/](\"http:\/\/118.25.99.91\/image\/DesignPattern\/image-20230227164857336.png\")
<\/div>\u8fea\u7c73\u7279\u6cd5\u5219\uff08LoD\uff09<\/h3>\n\n\n\n
\n
\n
\/\/ \u8fdd\u53cd\u8fea\u7c73\u7279\u6cd5\u5219\uff1a\u660e\u661f\u4eb2\u529b\u4eb2\u4e3a\u5904\u7406\u6240\u6709\u4e8b\u52a1\npublic class StarBad {\n public void meetFans() { \/* ... *\/ }\n public void negotiateBusiness() { \/* ... *\/ }\n public void handleContract() { \/* ... *\/ }\n public void attendShow() { \/* ... *\/ }\n \/\/ \u4f9d\u8d56\u8fc7\u591a\uff0c\u7cbe\u529b\u5206\u6563\n}\n\n\/\/ \u9075\u5faa\u8fea\u7c73\u7279\u6cd5\u5219\uff1a\u901a\u8fc7\u7ecf\u7eaa\u4eba\u5904\u7406\npublic class Agent {\n private Star star;\n private Fans fans;\n private Company company;\n \n public void arrangeMeeting() {\n \/\/ \u5b89\u6392\u7c89\u4e1d\u89c1\u9762\u4f1a\n }\n \n public void negotiateContract() {\n \/\/ \u4e0e\u5546\u5bb6\u6d3d\u8c08\n }\n}\n\npublic class Star {\n private Agent agent; \/\/ \u53ea\u4f9d\u8d56\u76f4\u63a5\u670b\u53cbAgent\n \n public void perform() { \/* \u53ea\u4e13\u6ce8\u8868\u6f14 *\/ }\n}<\/code><\/pre>\n\n\n\n![\"\u8fdd\u53cd\u8fea\u7c73\u7279\u6cd5\u5219\"\/](\"http:\/\/118.25.99.91\/image\/DesignPattern\/image-20230227172132757.png\")
<\/div>![\"\u9075\u5faa\u8fea\u7c73\u7279\u6cd5\u5219\"\/](\"http:\/\/118.25.99.91\/image\/DesignPattern\/image-20230227174049484.png\")
<\/div>\/\/ \u274c \u8fdd\u53cd\u8fea\u7c73\u7279\u6cd5\u5219\uff1a\u8001\u5e08\u76f4\u63a5\u4f9d\u8d56\u4e86Student\npublic class TeacherBad {\n public void command() {\n \/\/ \u76f4\u63a5\u521b\u5efaStudent\uff08\u5c40\u90e8\u53d8\u91cf\uff0c\u4e0d\u662f\u76f4\u63a5\u670b\u53cb\uff09\n List<Student> students = new ArrayList<>();\n for (int i = 0; i < 20; i++) {\n students.add(new Student());\n }\n \n \/\/ \u4f9d\u8d56StudentLeader\n StudentLeader leader = new StudentLeader();\n System.out.println(\"\u6e05\u70b9\u4eba\u6570\u5b8c\u6bd5\uff0c\u603b\u5171\u6709:\" + leader.counts(students) + \"\u4eba\");\n }\n}\n\n\/\/ \u2705 \u9075\u5faa\u8fea\u7c73\u7279\u6cd5\u5219\uff1a\u8001\u5e08\u53ea\u4f9d\u8d56\u73ed\u957f\npublic class Teacher {\n \/\/ \u4ec5\u8026\u5408StudentLeader\uff08\u65b9\u6cd5\u53c2\u6570\uff0c\u76f4\u63a5\u670b\u53cb\uff09\n public void command(StudentLeader leader) {\n System.out.println(\"\u6e05\u70b9\u4eba\u6570\u5b8c\u6bd5\uff0c\u603b\u5171\u6709:\" + leader.counts() + \"\u4eba\");\n }\n}\n\npublic class StudentLeader {\n private List<Student> students; \/\/ Student\u662f\u6210\u5458\u53d8\u91cf\uff0c\u76f4\u63a5\u670b\u53cb\n \n public StudentLeader(List<Student> students) {\n this.students = students;\n }\n \n public int counts() {\n return students.size();\n }\n}\n\n\/\/ \u6d4b\u8bd5\npublic class TaskTest {\n public static void main(String[] args) {\n System.out.println(\"\u5468\u672b\u6536\u5047\uff0c\u5b66\u6821\u9886\u5bfc\u547d\u4ee4\u8001\u5e08\u53bb\u70b9\u540d.....\");\n List<Student> students = new ArrayList<>();\n for (int i = 0; i < 20; i++) {\n students.add(new Student());\n }\n Teacher teacher = new Teacher();\n teacher.command(new StudentLeader(students));\n }\n}<\/code><\/pre>\n\n\n\n\u63a5\u53e3\u9694\u79bb\u539f\u5219\uff08ISP\uff09<\/h3>\n\n\n\n
\n
\/\/ \u274c \u5e9e\u5927\u63a5\u53e3\uff0c\u8fdd\u53cdISP\npublic interface CloudProvider {\n void createServer(); \/\/ \u521b\u5efa\u670d\u52a1\u5668\n void deleteServer(); \/\/ \u5220\u9664\u670d\u52a1\u5668\n void createDatabase(); \/\/ \u521b\u5efa\u6570\u636e\u5e93\uff08\u963f\u91cc\u4e91\u652f\u6301\uff0c\u817e\u8baf\u4e91\u6682\u4e0d\u652f\u6301\uff09\n void createCache(); \/\/ \u521b\u5efa\u7f13\u5b58\n void createCDN(); \/\/ \u521b\u5efaCDN\n void createKubernetes(); \/\/ \u521b\u5efaK8s\uff08\u963f\u91cc\u4e91\u652f\u6301\uff0c\u817e\u8baf\u4e91\u6682\u4e0d\u652f\u6301\uff09\n}\n\n\/\/ \u817e\u8baf\u4e91\u5b9e\u73b0\u7c7b - \u88ab\u8feb\u5b9e\u73b0\u4e0d\u652f\u6301\u7684\u65b9\u6cd5\npublic class TencentCloud implements CloudProvider {\n @Override\n public void createServer() { \/* ... *\/ }\n \n @Override\n public void deleteServer() { \/* ... *\/ }\n \n @Override\n public void createDatabase() {\n throw new UnsupportedOperationException(\"\u6682\u4e0d\u652f\u6301\");\n }\n \n @Override\n public void createCache() { \/* ... *\/ }\n \n @Override\n public void createCDN() { \/* ... *\/ }\n \n @Override\n public void createKubernetes() {\n throw new UnsupportedOperationException(\"\u6682\u4e0d\u652f\u6301\");\n }\n}<\/code><\/pre>\n\n\n\n\/\/ \u2705 \u62c6\u5206\u4e3a\u6700\u5c0f\u63a5\u53e3\npublic interface ComputeService {\n void createServer();\n void deleteServer();\n}\n\npublic interface DatabaseService {\n void createDatabase();\n}\n\npublic interface CacheService {\n void createCache();\n}\n\npublic interface CDNService {\n void createCDN();\n}\n\n\/\/ \u963f\u91cc\u4e91\u5b9e\u73b0 - \u5b9e\u73b0\u9700\u8981\u7684\u63a5\u53e3\npublic class AliyunProvider implements ComputeService, DatabaseService, \n CacheService, CDNService {\n \/\/ \u5b9e\u73b0\u6240\u6709\u65b9\u6cd5\n}\n\n\/\/ \u817e\u8baf\u4e91\u5b9e\u73b0 - \u53ea\u5b9e\u73b0\u652f\u6301\u7684\u63a5\u53e3\npublic class TencentProvider implements ComputeService, CacheService, CDNService {\n \/\/ \u65e0\u9700\u5b9e\u73b0\u4e0d\u652f\u6301\u7684\u529f\u80fd\n}<\/code><\/pre>\n\n\n\n![\"\u8fdd\u53cd\u63a5\u53e3\u9694\u79bb\u539f\u5219\"\/](\"http:\/\/118.25.99.91\/image\/DesignPattern\/image-20230228094107478.png\")
<\/div>![\"\u9075\u5faa\u63a5\u53e3\u9694\u79bb\u539f\u5219\"\/](\"http:\/\/118.25.99.91\/image\/DesignPattern\/image-20230228094804270.png\")
<\/div>\u4f9d\u8d56\u5012\u7f6e\u539f\u5219\uff08DIP\uff09<\/h3>\n\n\n\n
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\n
\/\/ \u5177\u4f53\u5b9e\u73b0\u7c7b\npublic class IntelCPU {\n public void work() { System.out.println(\"Intel CPU working...\"); }\n}\n\npublic class KingstonMemory {\n public void load() { System.out.println(\"Kingston Memory loading...\"); }\n}\n\npublic class SeagateDisk {\n public void read() { System.out.println(\"Seagate Disk reading...\"); }\n}\n\n\/\/ \u274c \u9ad8\u5c42\u6a21\u5757\u76f4\u63a5\u4f9d\u8d56\u5e95\u5c42\u6a21\u5757\npublic class Computer {\n private IntelCPU cpu; \/\/ \u76f4\u63a5\u4f9d\u8d56\u5177\u4f53\u7c7b\n private KingstonMemory memory; \/\/ \u76f4\u63a5\u4f9d\u8d56\u5177\u4f53\u7c7b\n private SeagateDisk disk; \/\/ \u76f4\u63a5\u4f9d\u8d56\u5177\u4f53\u7c7b\n \n public void start() {\n cpu.work();\n memory.load();\n disk.read();\n }\n}\n\/\/ \u66f4\u6362AMD CPU\uff1f\u9700\u8981\u4fee\u6539Computer\u7c7b\uff01<\/code><\/pre>\n\n\n\n\/\/ \u2705 \u5b9a\u4e49\u62bd\u8c61\u63a5\u53e3\npublic interface CPU {\n void work();\n}\n\npublic interface Memory {\n void load();\n}\n\npublic interface Disk {\n void read();\n}\n\n\/\/ \u5177\u4f53\u5b9e\u73b0\npublic class IntelCPU implements CPU {\n @Override\n public void work() { System.out.println(\"Intel CPU working...\"); }\n}\n\npublic class AMDCPU implements CPU {\n @Override\n public void work() { System.out.println(\"AMD CPU working...\"); }\n}\n\n\/\/ \u9ad8\u5c42\u6a21\u5757\u4f9d\u8d56\u62bd\u8c61\npublic class Computer {\n private CPU cpu; \/\/ \u4f9d\u8d56\u62bd\u8c61\n private Memory memory; \/\/ \u4f9d\u8d56\u62bd\u8c61\n private Disk disk; \/\/ \u4f9d\u8d56\u62bd\u8c61\n \n public Computer(CPU cpu, Memory memory, Disk disk) {\n this.cpu = cpu;\n this.memory = memory;\n this.disk = disk;\n }\n \n public void start() {\n cpu.work();\n memory.load();\n disk.read();\n }\n}\n\n\/\/ \u4f7f\u7528 - \u53ef\u4ee5\u8f7b\u677e\u66f4\u6362\u7ec4\u4ef6\nComputer computer1 = new Computer(new IntelCPU(), new KingstonMemory(), new SeagateDisk());\nComputer computer2 = new Computer(new AMDCPU(), new ADATAMemory(), new SanDiskDisk());<\/code><\/pre>\n\n\n\n![\"\u8fdd\u53cd\u4f9d\u8d56\u5012\u7f6e\"\/](\"http:\/\/118.25.99.91\/image\/DesignPattern\/image-20230228101419968.png\")
<\/div>![\"\u9075\u5faa\u4f9d\u8d56\u5012\u7f6e\"\/](\"http:\/\/118.25.99.91\/image\/DesignPattern\/image-20230228101702714.png\")
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\n\n\n\n\u672c\u7ae0\u5c0f\u7ed3<\/h3>\n\n\n\n
\u250c\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2510\n\u2502 SOLID\u539f\u5219\u901f\u8bb0\u8868 \u2502\n\u251c\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2524\n\u2502 S - Single Responsibility \u4e00\u4e2a\u7c7b\u53ea\u505a\u4e00\u4ef6\u4e8b \u2502\n\u2502 O - Open\/Closed \u5bf9\u6269\u5c55\u5f00\u653e\uff0c\u5bf9\u4fee\u6539\u5c01\u95ed \u2502\n\u2502 L - Liskov Substitution \u5b50\u7c7b\u8981\u80fd\u66ff\u6362\u7236\u7c7b \u2502\n\u2502 I - Interface Segregation \u63a5\u53e3\u8981\u5c0f\u800c\u4e13 \u2502\n\u2502 D - Dependency Inversion \u4f9d\u8d56\u62bd\u8c61\uff0c\u4e0d\u4f9d\u8d56\u5177\u4f53 \u2502\n\u2514\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2500\u2518<\/code><\/pre>\n\n\n\n\u521b\u5efa\u578b\u6a21\u5f0f<\/h2>\n\n\n\n
\u5355\u4f8b\u6a21\u5f0f\uff08Singleton\uff09<\/h3>\n\n\n\n
![\"\u5355\u4f8b\u6a21\u5f0fUML\"\/](\"http:\/\/118.25.99.91\/image\/DesignPattern\/image-20230228105104449.png\")
<\/div>![\"\u5355\u4f8b\u6a21\u5f0f\u7c7b\u56fe\"\/](\"http:\/\/118.25.99.91\/image\/DesignPattern\/image-20230228111143834.png\")
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package com.cskaoyan.pattern.singleton;\n\n\/**\n * \u997f\u6c49\u5f0f\u5355\u4f8b\u6a21\u5f0f\n * \u7279\u70b9\uff1a\u7c7b\u52a0\u8f7d\u65f6\u5373\u521b\u5efa\u5b9e\u4f8b\uff0c\u7ebf\u7a0b\u5b89\u5168\uff0c\u4f46\u4e0d\u652f\u6301\u61d2\u52a0\u8f7d\n *\/\npublic class Singleton1 {\n\n \/\/ 1. \u521b\u5efa\u79c1\u6709\u9759\u6001\u5b9e\u4f8b\u5bf9\u8c61\uff08\u7c7b\u52a0\u8f7d\u65f6\u521d\u59cb\u5316\uff09\n private static final Singleton1 INSTANCE = new Singleton1();\n\n \/\/ 2. \u79c1\u6709\u5316\u6784\u9020\u51fd\u6570\uff0c\u9632\u6b62\u5916\u90e8\u5b9e\u4f8b\u5316\n private Singleton1() {}\n\n \/\/ 3. \u63d0\u4f9b\u5168\u5c40\u8bbf\u95ee\u70b9\n public static Singleton1 getInstance() {\n return INSTANCE;\n }\n}<\/code><\/pre>\n\n\n\n\u4f18\u70b9<\/th> \u7f3a\u70b9<\/th><\/tr><\/thead> \u7ebf\u7a0b\u5b89\u5168\uff08\u7c7b\u52a0\u8f7d\u673a\u5236\u4fdd\u8bc1\uff09<\/td> \u4e0d\u652f\u6301\u61d2\u52a0\u8f7d<\/td><\/tr> \u5b9e\u73b0\u7b80\u5355\uff0c\u65e0\u9700\u52a0\u9501<\/td> \u5982\u679c\u5bf9\u8c61\u8f83\u5927\u4e14\u4e00\u76f4\u672a\u4f7f\u7528\uff0c\u6d6a\u8d39\u5185\u5b58<\/td><\/tr> \u83b7\u53d6\u5bf9\u8c61\u901f\u5ea6\u5feb<\/td> \u65e0\u6cd5\u4f20\u9012\u53c2\u6570\u521d\u59cb\u5316<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n package com.cskaoyan.pattern.singleton;\n\n\/**\n * \u61d2\u6c49\u5f0f\u5355\u4f8b\u6a21\u5f0f - \u7ebf\u7a0b\u4e0d\u5b89\u5168\u7248\u672c\n * \u7279\u70b9\uff1a\u652f\u6301\u61d2\u52a0\u8f7d\uff0c\u4f46\u591a\u7ebf\u7a0b\u73af\u5883\u4e0b\u53ef\u80fd\u521b\u5efa\u591a\u4e2a\u5b9e\u4f8b\n *\/\npublic class Singleton2 {\n\n private static Singleton2 instance;\n\n \/\/ \u79c1\u6709\u5316\u6784\u9020\u51fd\u6570\n private Singleton2() {}\n\n \/\/ \u5224\u65ad\u5f53\u524d\u5bf9\u8c61\u662f\u5426\u5df2\u7ecf\u88ab\u521b\u5efa\n public static Singleton2 getInstance() {\n if (instance == null) { \/\/ \u7ebf\u7a0bA\u6267\u884c\u5230\u8fd9\u91cc\u88ab\u5207\u6362\n instance = new Singleton2(); \/\/ \u7ebf\u7a0bB\u6267\u884c\u5b8c\uff0c\u7ebf\u7a0bA\u518d\u6b21\u6267\u884c\uff0c\u53c8\u521b\u5efa\u4e00\u4e2a\u5bf9\u8c61\n }\n return instance;\n }\n}<\/code><\/pre>\n\n\n\n![\"\u591a\u7ebf\u7a0b\u95ee\u9898\"\/](\"http:\/\/118.25.99.91\/image\/DesignPattern\/image-20230228114741374.png\")
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