一文講透SpringMVC

{"type":"doc","content":[{"type":"heading","attrs":{"align":null,"level":2},"content":[{"type":"text","text":"MVC基礎知識與應用"}]},{"type":"heading","attrs":{"align":null,"level":3},"content":[{"type":"text","text":"MVC體系結構"}]},{"type":"heading","attrs":{"align":null,"level":4},"content":[{"type":"text","text":"三層架構"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"在B / S架構中，系統標準的三層架構爲：表現層 、業務層、持久層。三層架構中，每一層各司其職，共同協作實現對功能的支持與實現。"}]},{"type":"bulletedlist","content":[{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"表現層"}]}]},{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"業務層"}]}]},{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"持久層"}]}]}]},{"type":"heading","attrs":{"align":null,"level":4},"content":[{"type":"text","text":"MVC設計模式"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"MVC全稱是Model View Controller，就是模型 - 視圖 - 控制器的縮寫。是一種用於設計Web應用程序表現層的模式。"}]},{"type":"bulletedlist","content":[{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"Model（模型）：模型包含了數據模型和業務模型，數據模型用於封裝數據，業務模型用於處理業務。"}]}]},{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"View（View ）：通常指的是jsp或者html。用於展示數據。"}]}]},{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"Controller（Controller）：負責應用程序與客戶端交互的核心入口。基本只負責接受請求和響應。"}]}]}]},{"type":"heading","attrs":{"align":null,"level":3},"content":[{"type":"text","text":"Spring MVC簡介"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"​ Spring MVC全稱是Spring Web MVC，是基於Java的實現MVC設計模式的請求驅動類型的輕量級Web框架，屬於Spring FrameWork的後續產品。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"​ Spring MVC已經成爲目前最流行的MVC框架之一，並且隨着Spring3.0的發佈，全面超過Struts2成爲最優秀的MVC框架。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"​ servlet / struts開發需要實現接口，Spring MVC可以實現接口Controller，也提供了註解方式，只需要一個註解就可以（簡便開發）。Spring MVC提供一整套註解，讓一個簡單的Java類成爲處理請求的控制器，不需要實現任何接口。並且對Restful編程風格提供了支持。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong"}],"text":"本質"},{"type":"text","text":" Spring MVC其實就是對Servlet的封裝，簡化了我們Servlet的開發。"}]},{"type":"image","attrs":{"src":"https://static001.geekbang.org/infoq/58/58e5276cded89de23f4341864d96dd6a.png","alt":null,"title":"","style":[{"key":"width","value":"100%"},{"key":"bordertype","value":"none"}],"href":"","fromPaste":false,"pastePass":false}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"heading","attrs":{"align":null,"level":4},"content":[{"type":"text","text":"開發流程"}]},{"type":"bulletedlist","content":[{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"web.xml配置DispatcherServlet前端控制器"}]}]}]},{"type":"codeblock","attrs":{"lang":"html"},"content":[{"type":"text","text":"\n \n dispatcherServlet\n org.springframework.web.servlet.DispatcherServlet\n \n \n \n \n dispatcherServlet\n /\n \n"}]},{"type":"bulletedlist","content":[{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"開發具體的處理業務邏輯Handler（@Controller / @RequestMapper）"}]}]}]},{"type":"codeblock","attrs":{"lang":"java"},"content":[{"type":"text","text":"@Controller\n@RequestMapping(value = \"/demo\")\npublic class DemoController {\n\n /**\n * SpringMVC 項目配置（三大核心組件）：\n * 1）配置前端控制器：org.springframework.web.servlet.DispatcherServlet(核心)\n * \n * dispatcherServlet\n * org.springframework.web.servlet.DispatcherServlet\n * \n * contextConfigLocation\n * classpath:springmvc.xml\n * \n * \n * \n * dispatcherServlet\n * /\n * \n * 2）配置配置視圖處理器：\n * \n * \n * \n * \n * 3）配置映射處理器（不指定，將自動匹配合適的映射處理器）：\n * \n */\n /**\n * 數據返回方式一：model和view封裝到對象中\n * ModelAndView對象內部包含了：ModelMap 和 Object view兩個屬性，分別用於封裝Model數據模型和View視圖\n * @return\n */\n @RequestMapping(value = \"/handler01\")\n public ModelAndView handler01() {\n LocalDateTime now = LocalDateTime.now();\n // 封裝了Model和View視圖\n ModelAndView modelAndView = new ModelAndView();\n // 封裝返回結果到Model中\n modelAndView.addObject(\"date\", now);\n // 設置返回的視圖名稱\n modelAndView.setViewName(\"success\");\n return modelAndView;\n }\n\n /**\n * 探究ModelMap / Model / Map之間的關係，爲什麼可以將數據存儲到域並且被視圖解析器讀取到？？？\n * class ModelMap extends LinkedHashMap 繼承了LinkedHashMap，LinkedHashMap又實現了Map接口\n * interface Model 只是一個接口\n * interface Map 只是一個接口\n *\n * ModelMap / Model / Map 在SpringMVC注入的時候打印的都是org.springframework.validation.support.BindingAwareModelMap對象\n * 探究 BindingAwareModelMap\n * class BindingAwareModelMap extends ExtendedModelMap\n * class ExtendedModelMap extends ModelMap implements Model\n *\n * 探究結果：BindingAwareModelMap繼承了ModelMap類，實現了Model接口，最終封裝數據的是BindingAwareModelMap\n *\n */\n\n /**\n * 數據返回方式二：view視圖路徑直接return,使用ModelMap封裝數據\n * ModelMap對象：org.springframework.validation.support.BindingAwareModelMap\n * @param modelMap\n * @return\n */\n @RequestMapping(value = \"/handler11\")\n public String handler11(ModelMap modelMap) {\n LocalDateTime now = LocalDateTime.now();\n modelMap.addAttribute(\"date\",now);\n System.out.println(\"--------------\" + modelMap.getClass());\n return \"success\";\n }\n\n /**\n * 數據返回方式三：view視圖路徑直接return,使用Model封裝數據\n * Model對象：org.springframework.validation.support.BindingAwareModelMap\n * @param model\n * @return\n */\n @RequestMapping(value = \"/handler12\")\n public String handler12(Model model) {\n LocalDateTime now = LocalDateTime.now();\n model.addAttribute(\"date\",now);\n System.out.println(\"--------------\" + model.getClass());\n return \"success\";\n }\n\n /**\n * 數據返回方式四：view視圖路徑直接return,使用Map封裝數據\n * Map對象：org.springframework.validation.support.BindingAwareModelMap\n * @param map\n * @return\n */\n @RequestMapping(value = \"/handler13\")\n public String handler13(Map map) {\n LocalDateTime now = LocalDateTime.now();\n map.put(\"date\",now);\n System.out.println(\"--------------\" + map.getClass());\n return \"success\";\n }\n\n /**\n * BindingAwareModelMap也可以封裝數據，因爲最終Spring就是通過這個對象將數據放入域中\n * @param bindingAwareModelMap\n * @return\n */\n @RequestMapping(value = \"/handler14\")\n public String handler14(BindingAwareModelMap bindingAwareModelMap) {\n LocalDateTime now = LocalDateTime.now();\n bindingAwareModelMap.put(\"date\",now);\n System.out.println(\"--------------\" + bindingAwareModelMap.getClass());\n return \"success\";\n }\n}\n"}]},{"type":"bulletedlist","content":[{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"springmvc.xml配置註解掃描、配置InternalResourceViewResolver視圖解析器、"},{"type":"codeinline","content":[{"type":"text","text":""}]},{"type":"text","text":"映射處理器"}]}]}]},{"type":"codeblock","attrs":{"lang":"html"},"content":[{"type":"text","text":"\t\n \n\n \n \n \n \n \n \n\n \n \n"}]},{"type":"bulletedlist","content":[{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"在web.xml的DispatcherServlet中配置springmvc.xml路徑"}]}]}]},{"type":"codeblock","attrs":{"lang":"html"},"content":[{"type":"text","text":" \n \n dispatcherServlet\n org.springframework.web.servlet.DispatcherServlet\n \n \n contextConfigLocation\n classpath:springmvc.xml\n \n \n"}]},{"type":"heading","attrs":{"align":null,"level":4},"content":[{"type":"text","text":"Spring MVC請求處理流程"}]},{"type":"image","attrs":{"src":"https://static001.geekbang.org/infoq/9b/9b48264b0f03e3759c7b5b8e2fd2f555.png","alt":null,"title":"","style":[{"key":"width","value":"100%"},{"key":"bordertype","value":"none"}],"href":"","fromPaste":false,"pastePass":false}},{"type":"heading","attrs":{"align":null,"level":5},"content":[{"type":"text","text":"流程說明"}]},{"type":"bulletedlist","content":[{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"1）用戶發送請求到前端控制器DispatcherServlet"}]}]},{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"2）DispatcherServlet接受到用戶發起的請求後調用HandlerMapping映射處理器"}]}]},{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"3）映射處理器根據請求的url找到具體的Handler（後端控制器），生成處理器對象以及處理器攔截器（有就生成）並將Handler返回給DispatcherServlet"}]}]},{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"4）DispatcherServlet調用HandlerAdapter處理器適配器去調用Handler"}]}]},{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"5）處理器適配器執行Handler"}]}]},{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"6）Handler處理完畢後返回ModelAndView給處理器適配器"}]}]},{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"7）處理器適配器將ModelAndView返回給前端控制器DispatcherServlet"}]}]},{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"8）前端控制器DispatcherServlet請求視圖解析器ViewResolver解析視圖"}]}]},{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"9）視圖解析器將解析後的視圖View返回給前端控制器DispatcherServlet"}]}]},{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"10）前端控制器DispatcherServlet對視圖渲染，就是將數據模型填充到request域中"}]}]},{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"11）前端控制器DispatcherServlet想用戶響應結果"}]}]}]},{"type":"heading","attrs":{"align":null,"level":3},"content":[{"type":"text","text":"Spring MVC九大組件"}]},{"type":"bulletedlist","content":[{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"HandlerMapping（處理器控制器）"}]}]},{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"HandlerAdapter（處理器適配器）"}]}]},{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"HandlerExceptionResolver（異常解析器）"}]}]},{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"ViewResolver（視圖解析器）"}]}]},{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"RequsetToViewNameTranslator"}]}]},{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"LocalResolver"}]}]},{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"ThemeResolver"}]}]},{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"MultipartResolver"}]}]},{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"FlashMapManager"}]}]}]},{"type":"heading","attrs":{"align":null,"level":3},"content":[{"type":"text","text":"請求參數綁定"}]},{"type":"heading","attrs":{"align":null,"level":4},"content":[{"type":"text","text":"基礎數據類型綁定"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"​ 簡單的基礎數據類型：八種基礎數據類型及其包裝類型，參數類型推薦使用包裝類類型，因爲基礎數據類型不可以爲null。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"​ Short / short 、Long / long 、Integer / int 、Float / float 、Double / double 、Char / char 、Boolean / boolean 、String"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong"}],"text":"說明"},{"type":"text","text":"：對於布爾值類型的參數，參數值只能爲trur / false / 1 / 0。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong"}],"text":"注意"},{"type":"text","text":"：綁定基礎數據類型，只需要直接聲明形參即可。建議請求參數和形參參數名稱一致，如不一致使用"},{"type":"codeinline","content":[{"type":"text","text":"@RequestParam"}]},{"type":"text","text":"註解。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong"}],"text":"html"}]},{"type":"codeblock","attrs":{"lang":"html"},"content":[{"type":"text","text":"

\n

測試用例：SpringMVC 接收簡單數據類型參數

\n 點擊測試\n

\n"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong"}],"text":"java"}]},{"type":"codeblock","attrs":{"lang":"java"},"content":[{"type":"text","text":"@RequestMapping(\"/handle03\")\npublic ModelAndView handle03(@RequestParam(\"ids\") Integer id,Boolean flag) {\n Date date = new Date();\n ModelAndView modelAndView = new ModelAndView();\n modelAndView.addObject(\"date\",date);\n modelAndView.setViewName(\"success\");\n return modelAndView;\n}\n"}]},{"type":"heading","attrs":{"align":null,"level":4},"content":[{"type":"text","text":"Pojo類型參數綁定"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong"}],"text":"html"}]},{"type":"codeblock","attrs":{"lang":"html"},"content":[{"type":"text","text":"

\n

測試用例：SpringMVC接收pojo類型參數

\n 點擊測試\n

\n"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong"}],"text":"java"}]},{"type":"codeblock","attrs":{"lang":"java"},"content":[{"type":"text","text":"/*\n * SpringMVC接收pojo類型參數 url：/demo/handle04?id=1&username=zhangsan\n * 接收pojo類型參數，直接形參聲明即可，類型就是Pojo的類型，形參名無所謂\n * 但是要求傳遞的參數名必須和Pojo的屬性名保持一致\n */\n@RequestMapping(\"/handle04\")\npublic ModelAndView handle04(User user) {\n Date date = new Date();\n ModelAndView modelAndView = new ModelAndView();\n modelAndView.addObject(\"date\",date);\n modelAndView.setViewName(\"success\");\n return modelAndView;\n}\n"}]},{"type":"heading","attrs":{"align":null,"level":4},"content":[{"type":"text","text":"Pojo包裝對象綁定"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong"}],"text":"html"}]},{"type":"codeblock","attrs":{"lang":"html"},"content":[{"type":"text","text":"

\n

測試用例：SpringMVC接收pojo包裝類型參數

\n 點擊測試\n

\n"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong"}],"text":"java"}]},{"type":"codeblock","attrs":{"lang":"java"},"content":[{"type":"text","text":"/*\n * QueryVo中有User user 屬性，需要將請求參數封裝到queryVo中\n * SpringMVC接收pojo包裝類型參數 url：/demo/handle05?user.id=1&user.username=zhangsan\n * 不管包裝Pojo與否，它首先是一個pojo，那麼就可以按照上述pojo的要求來\n * 1、綁定時候直接形參聲明即可\n * 2、傳參參數名和pojo屬性保持一致，如果不能夠定位數據項，那麼通過屬性名 + \".\" 的方式進一步鎖定數據\n *\n */\n@RequestMapping(\"/handle05\")\npublic ModelAndView handle05(QueryVo queryVo) {\n Date date = new Date();\n ModelAndView modelAndView = new ModelAndView();\n modelAndView.addObject(\"date\",date);\n modelAndView.setViewName(\"success\");\n return modelAndView;\n}\n"}]},{"type":"heading","attrs":{"align":null,"level":4},"content":[{"type":"text","text":"日期類型綁定"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong"}],"text":"html"}]},{"type":"codeblock","attrs":{"lang":"html"},"content":[{"type":"text","text":"

\n

測試用例：SpringMVC接收日期類型參數

\n 點擊測試\n

\n"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong"}],"text":"java"}]},{"type":"codeblock","attrs":{"lang":"java"},"content":[{"type":"text","text":"/**\n * 綁定日期類型參數\n * 定義一個SpringMVC的類型轉換器 接口，擴展實現接口接口，註冊你的實現\n * @param birthday\n * @return\n */\n@RequestMapping(\"/handle06\")\npublic ModelAndView handle06(Date birthday) {\n Date date = new Date();ModelAndView modelAndView = new ModelAndView();\n modelAndView.addObject(\"date\",date);\n modelAndView.setViewName(\"success\");\n return modelAndView;\n}\n"}]},{"type":"heading","attrs":{"align":null,"level":5},"content":[{"type":"text","text":"自定義類型轉化器"}]},{"type":"codeblock","attrs":{"lang":"java"},"content":[{"type":"text","text":"/**\n * Converter\n * S : 是傳遞進來的數據類型\n * T : 是處理後需要返回的數據類型\n * @Author zhang yong jun\n * @time 2020/6/11 11:25\n */\npublic class DateConverter implements Converter {\n\n private static final SimpleDateFormat SDF = new SimpleDateFormat(\"yyyy-MM-dd\");\n\n @Override\n public Date convert(String s) {\n Date parse = null;\n try {\n parse = SDF.parse(s);\n } catch (ParseException e) {\n e.printStackTrace();\n }\n return parse;\n }\n}\n"}]},{"type":"heading","attrs":{"align":null,"level":5},"content":[{"type":"text","text":"配置自定義類型轉換器"}]},{"type":"codeblock","attrs":{"lang":"html"},"content":[{"type":"text","text":"\n\n\n\n \n \n \n \n \n\n"}]},{"type":"heading","attrs":{"align":null,"level":3},"content":[{"type":"text","text":"對Restful風格請求的支持"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"​ Restful是一種web軟件架構風格，它不是標準也不是協議，只是倡導url設計的時候使用資源定義以及資源操作的風格。"}]},{"type":"heading","attrs":{"align":null,"level":4},"content":[{"type":"text","text":"Restful是什麼"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"​ REST（Representational State Transfer）描述了一個架構樣式的網絡系統。它由Roy Fielding在2000年的博士論文中提出，Roy Fielding是HTTP規範的主要編寫者之一。REST相比SOAP（Simple Object Access protocol，簡單對象訪問協議）和XML-RPC更加簡單明瞭，REST更傾向於簡單輕量的方法設計和實現。所以REST是一種設計風格。"}]},{"type":"heading","attrs":{"align":null,"level":5},"content":[{"type":"text","text":"Restful的優點"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"結構清晰、符合標準、易於理解、方便擴展"}]},{"type":"heading","attrs":{"align":null,"level":5},"content":[{"type":"text","text":"Restful的特徵"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong"}],"text":"資源（Resources）:"},{"type":"text","text":" 網絡上的一個實體，可以是一段文本、一張圖片、一首歌曲、一種服務。可以用URI（統一資源定位符）指定它，每種資源對應一個特定的URI。要獲得資源只需要訪問這個資源的URI即可。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong"}],"text":"表現層（Representation）:"},{"type":"text","text":" 把資源呈現出來的形式，叫做表現層。比如：文本用txt格式、HTML格式、XML格式、JSON格式表現。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong"}],"text":"狀態轉化（State Transfer）:"},{"type":"text","text":" 每一個請求，就代表了客戶端和服務器的一次交互。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"HTTP協議是一個無狀態協議，所有的狀態都保存在服務器端。如果客戶端想要操作服務器，就必須通過一些手段，讓服務器端發生"},{"type":"text","marks":[{"type":"strong"}],"text":"狀態轉化"},{"type":"text","text":"。具體在HTTP協議中有四個表示操作方式的動詞：PUT / DELETE / GET / POST。"}]},{"type":"heading","attrs":{"align":null,"level":5},"content":[{"type":"text","text":"Restful風格URL"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"互聯網所有的一切都是資源，要求URL中只有表示資源的名稱，沒有動詞。"}]},{"type":"heading","attrs":{"align":null,"level":5},"content":[{"type":"text","text":"Restful資源操作"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"使用HTTP請求中的method方法put（更新） / delete（刪除） / post（新增） / get（查詢）來操作資源。但是由於安全性問題主要使用post和get。put和delete基本不使用。如果強制要使用put和delete，可以在請求中使用post並攜帶參數_method=put，服務端再配置請求方式過濾器，如果請求參數中有"},{"type":"codeinline","content":[{"type":"text","text":"__method"}]},{"type":"text","text":"就會轉換請求方式"},{"type":"codeinline","content":[{"type":"text","text":"org.springframework.web.filter.HiddenHttpMethodFilter"}]},{"type":"text","text":"。"}]},{"type":"heading","attrs":{"align":null,"level":5},"content":[{"type":"text","text":"Restful請求方式轉換"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong"}],"text":"html"}]},{"type":"codeblock","attrs":{"lang":"html"},"content":[{"type":"text","text":"\n

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modelAndView;\n}\n/*\n * restful delete /demo/handle/15\n */\n@RequestMapping(value = \"/handle/{id}\",method = {RequestMethod.DELETE})\npublic ModelAndView handleDelete(@PathVariable(\"id\") Integer id) {\n Date date = new Date();\n ModelAndView modelAndView = new ModelAndView();\n modelAndView.addObject(\"date\",date);\n modelAndView.setViewName(\"success\");\n return modelAndView;\n}\n"}]},{"type":"heading","attrs":{"align":null,"level":3},"content":[{"type":"text","text":"Ajax Json交互"}]},{"type":"heading","attrs":{"align":null,"level":4},"content":[{"type":"text","text":"什麼是Json"}]},{"type":"bulletedlist","content":[{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"JSON 指的是 JavaScript 對象表示法（"},{"type":"text","marks":[{"type":"strong"}],"text":"J"},{"type":"text","text":"ava"},{"type":"text","marks":[{"type":"strong"}],"text":"S"},{"type":"text","text":"cript "},{"type":"text","marks":[{"type":"strong"}],"text":"O"},{"type":"text","text":"bject "},{"type":"text","marks":[{"type":"strong"}],"text":"N"},{"type":"text","text":"otation）"}]}]},{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"JSON 是輕量級的文本數據交換格式"}]}]},{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"JSON 獨立於語言：JSON 使用 Javascript語法來描述數據對象，但是 JSON 仍然獨立於語言和平臺。JSON 解析器和 JSON 庫支持許多不同的編程語言。 目前非常多的動態（PHP，JSP，.NET）編程語言都支持JSON"}]}]}]},{"type":"heading","attrs":{"align":null,"level":4},"content":[{"type":"text","text":"Json的語法"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"JSON 語法是 JavaScript 對象表示語法的子集。"}]},{"type":"bulletedlist","content":[{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"數據在名稱/值對"}]}]},{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"數據由逗號分隔"}]}]},{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"大括號保存對象"}]}]},{"type":"listitem","content":[{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"中括號保存數組"}]}]}]},{"type":"heading","attrs":{"align":null,"level":4},"content":[{"type":"text","text":"@RequestBody註解"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"@ReqeustBody註解是Spring MVC對Json的支持，作用是將用戶請求的Json格式數據解析轉換爲對應的參數對象。這個註解解析的是Post請求的body區域參數。"}]},{"type":"heading","attrs":{"align":null,"level":4},"content":[{"type":"text","text":"@ResponseBody註解"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"@ResponseBody註解是Spring MVC對Json的支持，作用是將Controller返回的對象通過轉換器轉換爲指定的格式之後，寫入到reqsponse對象的body區域。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong"}],"text":"注意"},{"type":"text","text":" 使用這個註解後返回結果不走視圖處理器，而是直接將數據寫入到輸出流中響應給客戶端。"}]},{"type":"heading","attrs":{"align":null,"level":4},"content":[{"type":"text","text":"Spring MVC使用Json交互"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong"}],"text":"pom引入jar"}]},{"type":"codeblock","attrs":{"lang":"html"},"content":[{"type":"text","text":"\n\n com.fasterxml.jackson.core\n jackson-core\n 2.9.0\n\n\n com.fasterxml.jackson.core\n jackson-databind\n 2.9.0\n\n\n com.fasterxml.jackson.core\n jackson-annotations\n 2.9.0\n\n\n"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","marks":[{"type":"strong"}],"text":"html"}]},{"type":"codeblock","attrs":{"lang":"html"},"content":[{"type":"text","text":"

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Ajax json交互

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multipart 文件上傳，寫法一

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multipart 文件上傳，方式二

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