一、整体流程（三大件：DispatcherServlet,HandlerMapping,HandlerAdapter）
二、具体步骤（对上图步骤做了精简化处理，便于理解）
第一步：浏览器付出请求
第二步：请求到达服务器（springmvc 对地址进行处理 ）前端控制器 （拿到地址）
第三步：前端控制器找处理器映射器 对地址进行处理 变成数据链 返回给前端控制器
第四步：去找适配器 适配根据数据链找到对应的处理器（就是我们自己写的那个controller类）
第五步：处理器进行业务处理 然后得到结果吧这个结果（把结果放到一个模型（modelandview）对象）给适配器 适配器中转给前端控制器
第六步：找视图解析器 把模型（modelandview）进行整理 整理后的结果有给前端控制器
第七步：把6步得到的结果进行页面的渲染得到一张页面同时响应回浏览器
三、开发步骤
1.导入依赖
2、配置前端控制器（配置在web.xml 参考servlet的配置方式）
3、在springMVC的核心配置文件里面配<mvc: 作用：相当于拥有了映射器和适配器
4、配视图解析器
5、使用的时候传入参数（模型（modelandview）对象）
四、代码演示
准备工作：导入依赖
1 <dependency>
2 <groupId>javax.servlet</groupId>
3 <artifactId>javax.servlet-api</artifactId>
4 <version>3.1.0</version>
5 <scope>provided</scope>
6 </dependency>
7 <dependency>
8 <groupId>javax.servlet.jsp</groupId>
9 <artifactId>javax.servlet.jsp-api</artifactId>
10 <version>2.3.3</version>
11 <scope>provided</scope>
12 </dependency>
13 <dependency>
14 <groupId>javax.servlet</groupId>
15 <artifactId>jstl</artifactId>
16 <version>1.2</version>
17 </dependency>
18 <!-- JSTL stop -->
19 <dependency>
20 <groupId>taglibs</groupId>
21 <artifactId>standard</artifactId>
22 <version>1.1.2</version>
23 </dependency>
24
25 <dependency>
26 <groupId>org.springframework</groupId>
27 <artifactId>spring-context</artifactId>
28 <version>5.1.8.RELEASE</version>
29 </dependency>
30 <dependency>
31 <groupId>org.springframework</groupId>
32 <artifactId>spring-webmvc</artifactId>
33 <version>5.1.8.RELEASE</version>
34 </dependency>
35 <dependency>
1、 创建 web.xml 文件
1 <?xml version="1.0" encoding="UTF-8"?>
2 <web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
3 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
4 xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd"
5 version="3.1">
6
7 <servlet>
8 <servlet-name>springmvc</servlet-name>
9 <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
10 <!--配置初始化参数，用于读取 SpringMVC 的配置文件
11 在springmvc配置文件中指定要扫描的controller所在的包的路径-->
12 <init-param>
13 <param-name>contextConfigLocation</param-name>
14 <param-value>classpath:springmvc.xml</param-value>
15 </init-param>
16
17 <!-- 配置 servlet 的对象的创建时间点：应用加载时创建。
18 取值只能是非 0 正整数，表示启动顺序 -->
19 <load-on-startup>1</load-on-startup>
20 </servlet>
21 <servlet-mapping>
22 <servlet-name>springmvc</servlet-name>
23 <!-- <url-pattern>*.do</url-pattern>-->
24 <url-pattern>/</url-pattern><!--接收所有请求-->
25 </servlet-mapping>
26
27 <filter>
28 <filter-name>encodingFilter</filter-name>
29 <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
30 <init-param>
31 <param-name>encoding</param-name>
32 <param-value>utf-8</param-value>
33 </init-param>
34 </filter>
35 <filter-mapping>
36 <filter-name>encodingFilter</filter-name>
37 <url-pattern>/*</url-pattern>
38 </filter-mapping>
39
40 </web-app>
2.创建springmvc.xml文件
1 <?xml version="1.0" encoding="UTF-8"?>
2 <beans xmlns="http://www.springframework.org/schema/beans"
3 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
4 xmlns:context="http://www.springframework.org/schema/context"
5 xmlns:mvc="http://www.springframework.org/schema/cache"
6
7 xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context https://www.springframework.org/schema/context/spring-context.xsd http://www.springframework.org/schema/cache http://www.springframework.org/schema/cache/spring-cache.xsd">
8 <!--指定要扫描的UserController所在的包的路径，这样就可以扫描类中的注解了，此时类中的注解才能正常被spring容器所操作-->
9 <context:component-scan base-package="com.heima.web"></context:component-scan>
10
11 <!--指明我就是要用requestMapping handler映射处理器
12 //两个原因：
13 版本原因 其实RequestMappingHandlerMapping在以前版本就已经有这个类了，但是5.0以前版本，默认并不是这个
14 其他的原因 转换 Jason转换 自定义格式转换 都需要他
15 -->
16 <!--<mvc:annotation-driven></mvc:annotation-driven>-->相当于有了映射器和适配器
17
18 <!--定制化内部视图解析器-->
19 <bean id="InternalResourceViewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver">
20
21 <property name="prefix" value="/WEB-INF/pages/"/>
22 <property name="suffix" value=".jsp"/>
23 </bean>
24 </beans>
3.创建UserController类
1 @Controller//1.把UserController这个类放进spring容器中
2 @RequestMapping("/user")
3 public class UserController {
4 @RequestMapping("/test1")//2.指定下面这个方法所映射的路径
5 public ModelAndView test1(ModelAndView modelAndView){
6 Date date = new Date();
7 String content = "当前时间："+date.toLocaleString();
8 //类似于request.setAttribute("属性名"，"属性值")
9 modelAndView.addObject("content",content);
10 //等同于request.getDispatcher("").forward(request,response)
11 modelAndView.setViewName("user/list");
12 return modelAndView;
13
14 }
15
16 @RequestMapping("/test2_1")
17 public ModelAndView test2(ModelAndView modelAndView,int id){
18 System.out.println(id);
19 Date date = new Date();
20 String content = "当前时间："+date.toLocaleString();
21 //类似于request.setAttribute("属性名"，"属性值")
22 modelAndView.addObject("content",content);
23 //等同于request.getDispatcher("").forward(request,response)
24 modelAndView.setViewName("hello/Hello");
25 return modelAndView;
26
27 }
28 @RequestMapping("/test2_2")
29 public ModelAndView test2_2(ModelAndView modelAndView,User user){
30 System.out.println(user);
31 Date date = new Date();
32 String content = "当前时间："+date.toLocaleString();
33 //类似于request.setAttribute("属性名"，"属性值")
34 modelAndView.addObject("content",content);
35 //等同于request.getDispatcher("").forward(request,response)
36 modelAndView.setViewName("hello/Hello");
37 return modelAndView;
38
39 }
40
41 @RequestMapping(value = "/test3",method = RequestMethod.POST)
42 public ModelAndView test3(ModelAndView modelAndView,User user){
43 System.out.println(user);
44 Date date = new Date();
45 String content = "当前时间："+date.toLocaleString();
46 //类似于request.setAttribute("属性名"，"属性值")
47 modelAndView.addObject("content",content);
48 //等同于request.getDispatcher("").forward(request,response)
49 modelAndView.setViewName("user/list");
50 return modelAndView;
51
52 }
53 /*params表示必须传的参数*/
54 @RequestMapping(value = "/test4",params = "username")
55 public ModelAndView test4(ModelAndView modelAndView,User user){
56 System.out.println(user);
57 Date date = new Date();
58 String content = "当前时间："+date.toLocaleString();
59 //类似于request.setAttribute("属性名"，"属性值")
60 modelAndView.addObject("content",content);
61 //等同于request.getDispatcher("").forward(request,response)
62 modelAndView.setViewName("user/list");
63 return modelAndView;
64
65 }
66
67 /*headers表示必须带"user-agent"请求头，这个默认带，换一个就报404了*/
68 @RequestMapping(value = "/test5",headers = "user-agent")//
69 public ModelAndView test5(ModelAndView modelAndView,User user){
70 System.out.println(user);
71 Date date = new Date();
72 String content = "当前时间："+date.toLocaleString();
73 //类似于request.setAttribute("属性名"，"属性值")
74 modelAndView.addObject("content",content);
75 //等同于request.getDispatcher("").forward(request,response)
76 modelAndView.setViewName("user/list");
77 return modelAndView;
78
79 }
80
81 /*@RequestParam 解决三个问题：1.大部分情况为了解决不传参问题，给定默认值
82 2.为了解决前后端参数名不同步问题，前后端参数名不一致
83 3.最后才是为了解决编译导致无参数名问题
84 */
85
86 @RequestMapping(value = "/test6")//@RequestParam(name = "id")可以防止setting-->java compiler-->generate debugging info没有被选中
87 //若没有被选中，程序只认识数据类型，却识别不出来数据名，@RequestParam(name = "id")可以强制指明数据名
88 public ModelAndView test6(ModelAndView modelAndView, @RequestParam(name = "id",defaultValue = "123") int id, @RequestParam(name = "username")String username,@RequestParam(name = "price")double price){
89 System.out.println(id+"---"+username+"---"+price);
90
91 Date date = new Date();
92 String content = "当前时间："+date.toLocaleString();
93 //类似于request.setAttribute("属性名"，"属性值")
94 modelAndView.addObject("content",content);
95 //等同于request.getDispatcher("").forward(request,response)
96 modelAndView.setViewName("user/list");
97 return modelAndView;
98
99 }
100
101 /*javaBean数据的绑定，注意参数名一定要与类里的属性名保持一致*/
102 @RequestMapping(value = "/test7")
103 public ModelAndView test7(ModelAndView modelAndView,User user){
104 System.out.println(user);
105
106 Date date = new Date();
107 String content = "当前时间："+date.toLocaleString();
108 //类似于request.setAttribute("属性名"，"属性值")
109 modelAndView.addObject("content",content);
110 //等同于request.getDispatcher("").forward(request,response)
111 modelAndView.setViewName("user/list");
112 return modelAndView;
113
114 }
115
116 /*javaBean数据的绑定，注意参数名一定要与类里的属性名保持一致*/
117 @RequestMapping(value = "/test8")
118 public ModelAndView test8(ModelAndView modelAndView,User user){
119 System.out.println(user);
120
121 Date date = new Date();
122 String content = "当前时间："+date.toLocaleString();
123 //类似于request.setAttribute("属性名"，"属性值")
124 modelAndView.addObject("content",content);
125 //等同于request.getDispatcher("").forward(request,response)
126 modelAndView.setViewName("user/list");
127 return modelAndView;
128
129 }
130
131
132 /*复合对象类型数组是参数数据的绑定，注意：前端name=user.username*/
133 @RequestMapping(value = "/test9")
134 public ModelAndView test9(ModelAndView modelAndView, QueryVo queryVo){
135 System.out.println(queryVo);
136
137 Date date = new Date();
138 String content = "当前时间："+date.toLocaleString();
139 //类似于request.setAttribute("属性名"，"属性值")
140 modelAndView.addObject("content",content);
141 //等同于request.getDispatcher("").forward(request,response)
142 modelAndView.setViewName("user/list");
143 return modelAndView;
144
145 }
146
147 /*复合对象类型map集合是对象数据的绑定，注意:前端name=smap['name'],定义map不能用map关键字*/
148 @RequestMapping(value = "/test10")
149 public ModelAndView test10(ModelAndView modelAndView, QueryVo queryVo){
150 System.out.println(queryVo);
151
152 Date date = new Date();
153 String content = "当前时间："+date.toLocaleString();
154 //类似于request.setAttribute("属性名"，"属性值")
155 modelAndView.addObject("content",content);
156 //等同于request.getDispatcher("").forward(request,response)
157 modelAndView.setViewName("user/list");
158 return modelAndView;
159 }
160
161 //练习11 演示复合对象类型list集合是对象参数绑定
162 @RequestMapping(value = "/test11")
163 public ModelAndView test11(ModelAndView modelAndView, QueryVo queryVo){
164 System.out.println(queryVo);
165
166 Date date = new Date();
167 String content = "当前时间："+date.toLocaleString();
168 //类似于request.setAttribute("属性名"，"属性值")
169 modelAndView.addObject("content",content);
170 //等同于request.getDispatcher("").forward(request,response)
171 modelAndView.setViewName("user/list");
172 return modelAndView;
173 }
174 }
4.创建User类，和QueryVo类
1 public class User {
2 private int id;
3 private String username;
4 private String desc;
5
6 @Override
7 public String toString() {
8 return "User{" +
9 "id=" + id +
10 ", username='" + username + '\'' +
11 ", desc='" + desc + '\'' +
12 '}';
13 }
14
15 public int getId() {
16 return id;
17 }
18
19 public void setId(int id) {
20 this.id = id;
21 }
22
23 public String getUsername() {
24 return username;
25 }
26
27 public void setUsername(String username) {
28 this.username = username;
29 }
30
31 public String getDesc() {
32 return desc;
33 }
34
35 public void setDesc(String desc) {
36 this.desc = desc;
37 }
38 }
1 public class QueryVo {
2 private User user;
3 private int age;
4 private String [] hobbies;
5 private Map smap;
6 private List<User> users;
7
8 public List<User> getUsers() {
9 return users;
10 }
11
12 public void setUsers(List<User> users) {
13 this.users = users;
14 }
15
16 public Map getSmap() {
17 return smap;
18 }
19
20 public void setSmap(Map smap) {
21 this.smap = smap;
22 }
23
24 public String[] getHobbies() {
25 return hobbies;
26 }
27
28 public void setHobbies(String[] hobbies) {
29 this.hobbies = hobbies;
30 }
31
32 public User getUser() {
33 return user;
34 }
35
36 public void setUser(User user) {
37 this.user = user;
38 }
39
40 public int getAge() {
41 return age;
42 }
43
44 public void setAge(int age) {
45 this.age = age;
46 }
47
48
49 @Override
50 public String toString() {
51 return "QueryVo{" +
52 "user=" + user +
53 ", age=" + age +
54 ", hobbies=" + Arrays.toString(hobbies) +
55 ", smap=" + smap +
56 ", users=" + users +
57 '}';
58 }
59 }5.创建前端页面list.jsp和index.jsp
list.jsp页面
1 <%@ page contentType="text/html;charset=UTF-8" language="java" %>
2 <html>
3 <head>
4 <title>Title</title>
5 </head>
6 <body>
7 <div style="text-align: center ;margin:100px 100px;color: blue;">
8 <font size="20px">${content}</font>
9 </div>
10 </body>
11 </html>
index.jsp页面
1 <%@ page contentType="text/html;charset=UTF-8" language="java" %>
2 <html>
3 <head>
4 <meta charset="UTF-8">
5 </head>
6 <body>
7 <h2>Hello World!</h2>
8 <div>
9 <fieldset>
10 <legend>练习1</legend>
11 <a href="/user/test1">常规使用1</a>
12 </fieldset>
13
14 <fieldset>
15 <legend>练习2</legend>
16 <a href="/user/test2_1">常规使用2</a>
17 </fieldset>
18
19 <fieldset>
20 <legend>练习3</legend>
21 <a href="/user/test3">指明请求必须是某类型</a>
22 <form action="/user/test3" method="post">
23 <input type="text" name="username"><br>
24 <input type="submit" value="点我提交">
25 </form>
26
27 </fieldset>
28
29 <fieldset>
30 <legend>练习4</legend>
31 <a href="/user/test4">演示RequestMapping必须传某某参数</a>
32 <form action="/user/test4" >
33 <input type="text" name="username"><br>
34 <input type="submit" value="点我提交">
35 </form>
36
37 </fieldset>
38
39 <fieldset>
40 <legend>练习5</legend>
41 <a href="/user/test5">演示带某某请求</a>
42 <form action="/user/test5" >
43 <input type="text" name="username"><br>
44 <input type="submit" value="点我提交">
45 </form>
46
47 </fieldset>
48
49 <fieldset>
50 <legend>练习6</legend>
51 <a href="/user/test6">演示简单类型的参数绑定</a>
52 <form action="/user/test6" >
53 id:<input type="text" name="id"><br>
54 username:<input type="text" name="username"><br>
55 price:<input type="text" name="price"><br>
56 <input type="submit" value="点我提交">
57 </form>
58
59 </fieldset>
60
61 <fieldset>
62 <legend>练习7</legend>
63 <a href="/user/test7">演示javaBean的参数绑定</a>
64 <form action="/user/test7" >
65 id:<input type="text" name="id"><br>
66 用户名:<input type="text" name="username"><br>
67 描述:<input type="text" name="desc"><br>
68 <input type="submit" value="点我提交">
69 </form>
70
71 </fieldset>
72
73 <fieldset>
74 <legend>练习8</legend>
75 <a href="/user/test8">演示复合对象的参数绑定</a>
76 <form action="/user/test8" >
77 id:<input type="text" name="user.id"><br>
78 age:<input type="text" name="age"><br>
79 用户名:<input type="text" name="user.username"><br>
80 描述:<input type="text" name="user.desc"><br>
81 <input type="submit" value="点我提交">
82 </form>
83
84 </fieldset>
85
86 <fieldset>
87 <legend>练习9</legend>
88 <a href="/user/test9">演示复合对象的数组参数的绑定</a>
89 <form action="/user/test9" >
90 id:<input type="text" name="user.id"><br>
91 age:<input type="text" name="age"><br>
92 用户名:<input type="text" name="user.username"><br>
93 描述:<input type="text" name="user.desc"><br>
94 爱好：<input type="checkbox" name="hobbies" value="抽烟">抽烟
95 <input type="checkbox" name="hobbies" value="喝酒">喝酒
96 <input type="checkbox" name="hobbies" value="烫头">烫头 <br>
97 <input type="submit" value="点我提交">
98 </form>
99 </fieldset>
100
101 <fieldset>
102 <legend>练习10</legend>
103 <a href="/user/test10">演示复合对象的map集合参数的绑定</a>
104 <form action="/user/test10" >
105 id:<input type="text" name="user.id"><br>
106 age:<input type="text" name="age"><br>
107 用户名:<input type="text" name="user.username"><br>
108 描述:<input type="text" name="user.desc"><br>
109 爱好：<input type="checkbox" name="hobbies" value="抽烟">抽烟
110 <input type="checkbox" name="hobbies" value="喝酒">喝酒
111 <input type="checkbox" name="hobbies" value="烫头">烫头 <br>
112 收款人：<input type="text" name="smap['name']">
113 电话：<input type="text" name="smap['tel']">
114 <input type="submit" value="点我提交">
115 </form>
116 </fieldset>
117
118 <fieldset>
119 <legend>练习11</legend>
120 <a href="/user/test11">演示复合对象类型list集合是对象的参数绑定</a>
121 <form action="/user/test11" >
122 用户名:<input type="text" name="user.username"><br>
123 爱好：<input type="checkbox" name="hobbies" value="抽烟">抽烟
124 <input type="checkbox" name="hobbies" value="喝酒">喝酒
125 <input type="checkbox" name="hobbies" value="烫头">烫头 <br>
126 收款人：<input type="text" name="smap['name']">
127 电话：<input type="text" name="smap['tel']">
128
129 收货人列表:<br>
130 收货人1:<input type="text" name="users[0].id"><input type="text" name="users[0].username"><br>
131 收货人2:<input type="text" name="users[1].id"><input type="text" name="users[1].username"><br>
132 收货人3:<input type="text" name="users[2].id"><input type="text" name="users[2].username"><br>
133 <input type="submit" value="点我提交">
134 </form>
135 </fieldset>
136 </div>
137 </body>
138 </html>
6.创建好的工程结构
