項目目錄
/springmvc-servlet.xml核心配置（自定義文件名）
注意：base-package要和controller層保持一致，涵蓋處理器映射器，處理器適配器，視圖解析器
其餘配置亙古不變，請放心使用
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:mvc="http://www.springframework.org/schema/mvc"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-4.3.xsd
http://www.springframework.org/schema/mvc
http://www.springframework.org/schema/mvc/spring-mvc-4.3.xsd">
//固定不變
<context:component-scan base-package="com.huang.controller" />
<mvc:default-servlet-handler />
<mvc:annotation-driven />
<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver" id="internalResourceViewResolver">
<property name="prefix" value="/WEB-INF/jsp/" />
<property name="suffix" value=".jsp" />
</bean>
</beans>
web.xml核心配置
org.springframework.web.servlet.DispatcherServlet和
org.springframework.web.filter.CharacterEncodingFilter是
springMVC提供的servlet調度器和編碼過濾器
注意的是前者匹配所有請求，後者匹配所有請求和所有jsp頁面
<servlet>
<servlet-name>springmvc</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<init-param>
<param-name>contextConfigLocation</param-name>
<param-value>classpath:springmvc-servlet.xml</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>springmvc</servlet-name>
<url-pattern>/</url-pattern>
</servlet-mapping>
<!-- <filter>-->
<!-- <filter-name>encoding</filter-name>-->
<!-- <filter-class>com.huang.filter.EncodingFilter</filter-class>-->
<!-- </filter>-->
<!-- <filter-mapping>-->
<!-- <filter-name>encoding</filter-name>-->
<!-- <url-pattern>/*</url-pattern>-->
<!-- </filter-mapping>-->
<filter>
<filter-name>encoding</filter-name>
<filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
<init-param>
<param-name>encoding</param-name>
<param-value>utf-8</param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name>encoding</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
controller示例
解析：
1.@Controller註解爲控制器
2.return "hello"會根據/springmvc-servlet.xml中視圖解析器的prefix和suffix來匹配url對應的前端頁面，如：url爲 ‘http://localhost:8080/hello/h1’則訪問項目目錄的/WEB-INF/jsp/hello.jsp
3.Model model；model.addAttribute(“msg”,“12121”);通常用來設置前端數據的回顯，下文jackson將詳細說明
@Controller
@RequestMapping("hello")
public class HelloController {
@RequestMapping("h1")
public String hello(Model model){
model.addAttribute("msg","12121");
return "hello";
}
@RequestMapping("h2")
public String hello1(Model model){
model.addAttribute("msg1","helloSpringMvc");
return "hello1";
}
}
/hello.jsp文件
${msg} 即對應 model.addAttribute(“msg”,“12121”);
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>Title</title>
</head>
<body>
${
msg}
</body>
</html>
controller層接受前端參數
前端代碼
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>Title</title>
</head>
<body>
<form action="/test1" method="post">
<input type="text" name="name">
<input type="submit">
</form>
</body>
</html>
controller層
@Controller
public class EncodingController {
@PostMapping("/test1")
public String test1(String name, Model model) {
System.out.println(name);
model.addAttribute("msg",name);
return "hello";
}
}
解析：
前端輸入框的name再沒使用jackson時，後臺拿到的就是name
@PostMapping("/test1") ：由於請求有多種方式，所以RequestMapping就對應有PostMapping/GetMapping/PutMapping等等，只要和前端的method="post"匹配即可，RequestMapping通配
public String test1(String name, Model model) {} 形參String name獲取到前端傳遞的參數
jackson使用
1.補充項目目錄
2.jar包
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-core</artifactId>
<version>2.10.0</version>
</dependency>
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-databind</artifactId>
<version>2.10.0</version>
</dependency>
3.工具類JsonUtils.getJson類
//抽取出公共的getJson類
public class JsonUtils {
public static String getJson(Object object,String dateFormat){
//jackson中有ObjectMapper對象
ObjectMapper mapper = new ObjectMapper();
// 不使用時間戳的方式
mapper.configure(SerializationFeature.WRITE_DATE_KEYS_AS_TIMESTAMPS,false);
// 自定義日期的格式
SimpleDateFormat sdf = new SimpleDateFormat(dateFormat);
mapper.setDateFormat(sdf);
try {
return mapper.writeValueAsString(object);
} catch (JsonProcessingException e) {
e.printStackTrace();
}
return null;
}
}
4.controller類示例
@Controller
public class JsonController {
@RequestMapping("j3")
@ResponseBody //不會執行任何視圖，只返回一個字符串
public String json3() throws JsonProcessingException {
List<User> userList = new ArrayList<User>();
userList.add(new User("黃傑1",20,"男"));
userList.add(new User("黃傑2",20,"男"));
userList.add(new User("黃傑3",20,"男"));
userList.add(new User("黃傑4",20,"男"));
return JsonUtils.getJson(userList,"");
}
}
5./springmvc-servlet.xml中配置解決json亂碼（都是寫死，可以存爲模板）
<mvc:annotation-driven>
<mvc:message-converters register-defaults="true">
<bean class="org.springframework.http.converter.StringHttpMessageConverter">
<property name="supportedMediaTypes" value="text/html;charset=UTF-8" />
</bean>
<bean id="jacksonMessageConverter" class="org.springframework.http.converter.json.MappingJackson2HttpMessageConverter">
<property name="supportedMediaTypes" value="application/json;charset=UTF-8" />
</bean>
</mvc:message-converters>
</mvc:annotation-driven>
6.\效果圖
到這裏恭喜你，你已經開始進入接口的編寫了
附錄：jar包依賴
這些依賴包，基本貫穿所有springMVC全過程，可以存爲模板
<dependencies>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-webmvc</artifactId>
<version>5.1.9.RELEASE</version>
</dependency>
<dependency>
<groupId>org.jetbrains</groupId>
<artifactId>annotations</artifactId>
<version>RELEASE</version>
<scope>compile</scope>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.11</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>servlet-api</artifactId>
<version>2.5</version>
<scope>provided</scope>
</dependency>
<!--jsp依賴-->
<dependency>
<groupId>javax.servlet.jsp</groupId>
<artifactId>jsp-api</artifactId>
<version>2.2</version>
</dependency>
<!--stl表達式的依賴-->
<dependency>
<groupId>javax.servlet.jsp.jstl</groupId>
<artifactId>jstl-api</artifactId>
<version>1.2</version>
</dependency>
<!--標準庫依賴-->
<dependency>
<groupId>taglibs</groupId>
<artifactId>standard</artifactId>
<version>1.1.2</version>
</dependency>
</dependencies>