springMVC笔记
土豆 2022/12/14 springMVCjava
# 入门
配置web.xml
在WEB-INF目录下创建 web.xml
配置Spring MVC的入口 DispatcherServlet，把所有的请求都提交到该Servlet
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_4_0.xsd"
version="4.0">
<!-- 配置所有请求由spring管理 -->
<servlet>
<servlet-name>DispatcherServlet</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<!-- 启动顺序，数字越小，启动越早 -->
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>DispatcherServlet</servlet-name>
<url-pattern>/</url-pattern>
</servlet-mapping>
</web-app>
springMVC配置文件
在WEB-INF目录下创建和配置DispatcherServlet-servlet.xml
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:mvc="http://www.springframework.org/schema/mvc"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:aop="http://www.springframework.org/schema/aop" xmlns:tx="http://www.springframework.org/schema/tx"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.2.xsd
http://www.springframework.org/schema/mvc
http://www.springframework.org/schema/mvc/spring-mvc-3.2.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-3.2.xsd
http://www.springframework.org/schema/aop
http://www.springframework.org/schema/aop/spring-aop-3.2.xsd
http://www.springframework.org/schema/tx
http://www.springframework.org/schema/tx/spring-tx-3.2.xsd">
<!-- 1.配置url处理映射-->
<bean class="org.springframework.web.servlet.handler.BeanNameUrlHandlerMapping"></bean>
<!-- 2.配置控制器处理适配器-->
<bean class="org.springframework.web.servlet.mvc.SimpleControllerHandlerAdapter"></bean>
<!-- 3.配置控制器-相当于配置了访问路径
class 要访问的java路径
-->
<bean name="/user" class="com.zh.web.controller.UserController"></bean>
<!-- 4.配置资源视图解析器-->
<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<!--前缀-->
<property name="prefix" value="/WEB-INF/views/"></property>
<!--后缀-->
<property name="suffix" value=".jsp"></property>
</bean>
</beans>
创建Controller控制器
//实现controller接口mvc.Controller下的
public class UserController implements Controller{
@Override
public ModelAndView handleRequest(HttpServletRequest request, HttpServletResponse response) throws Exception {
//返回jsp视图前缀/WEB-INF/views/user/userlist后缀.jsp将拼接起来
ModelAndView mv = new ModelAndView("user/userlist");
//存入数据让jsp取
mv.addObject("name","张三");
return mv;
}
}
创建jsp页面
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>用户列表</title>
</head>
<body>
用户列表<br>
${name}
</body>
</html>
运行项目
# 视图定位
new ModelAndView("index");
<!-- 配置资源视图解析器-->
<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<!--前缀-->
<property name="prefix" value="/WEB-INF/views/"></property>
<!--后缀-->
<property name="suffix" value=".jsp"></property>
</bean>
controller
//实现controller接口mvc.Controller下的
public class UserController implements Controller{
@Override
public ModelAndView handleRequest(HttpServletRequest request, HttpServletResponse response) throws Exception {
//返回jsp视图前缀/WEB-INF/views/user/userlist后缀.jsp将拼接起来
ModelAndView mv = new ModelAndView("user/userlist");
//存入数据让jsp取
mv.addObject("name","张三");
return mv;
}
}
# 注解方式
配置文件
<!-- 注解配置控制器-->
<!-- 1.配置扫描包:配置要扫描的包-->
<context:component-scan base-package="com.zh.web.controller"/>
<!-- 2可省略处理映射和适配器的配置-->
<mvc:annotation-driven/>
<!-- 3.配置资源视图解析器-->
<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<!--前缀-->
<property name="prefix" value="/WEB-INF/views/"></property>
<!--后缀-->
<property name="suffix" value=".jsp"></property>
</bean>
controller修改
@Controller
public class UserController{
@RequestMapping("useradd")
public String userAdd(){
return "/user/useradd";
}
}
控制台
可访问useradd.jsp
http://localhost/springmvc/useradd
# RequestMapping详解
@RequestMapping(“list”)
@RequestMapping(“/list”)
@RequestMapping(value=”/list”)
@RequestMapping(value = "/list3",method=RequestMethod.POST) //只能使用POST方法
@RequestMapping(value = "/list3",method=RequestMethod.Get) //只能使用GET方法
# RestFul 风格
概念
Restful就是一个资源定位及资源操作的风格。不是标准也不是协议，只是一种风格。基于这个风格设计的软件可以更简洁，更有层次，更易于实现缓存等机制。
功能
资源：互联网所有的事物都可以被抽象为资源
资源操作：使用POST、DELETE、PUT、GET，使用不同方法对资源进行操作。
使用 @PathVariable 注解，让方法参数的值对应绑定到一个URI模板变量上
@Controller
public class UserController{
@RequestMapping("/add/{id}/{name}"。)
public String userAdd(@PathVariable("id") Integer id,@PathVariable("name") String name){
System.out.println("id:"+id+",name"+name)
return "success";
}
}
配置过滤器
- get请求不需要过滤器
- post,put,delete需要配置过滤器
<!-- 将POST请求转化为DELETE或者是PUT 要用_method指定真正的请求参数-->
<filter>
<filter-name>HiddenHttpMethodFilter</filter-name>
<filter-class>org.springframework.web.filter.HiddenHttpMethodFilter</filter-class>
</filter>
<filter-mapping>
<filter-name>HiddenHttpMethodFilter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
接受请求
@Controller
public class UserController{
// PUT GET POST DELETE
@RequestMapping(value = "/add/{id}/{name}",method=RequestMethod.PUT)
public String userAdd(@PathVariable("id") Integer id,@PathVariable("name") String name){
System.out.println("id:"+id+",name"+name)
return "success";
}
}
# 中文乱码问题
<filter>
<filter-name>CharacterEncodingFilter</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>CharacterEncodingFilter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
# 表单数据接收
# 基本类型
表单页
<!-- 注册页面 -->
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>注册</title>
</head>
<body>
<form action="${pageContext.request.contextPath}/user/register.do" method="post">
用户名:<input type="text" name="username"><br>
密码:<input type="text" name="password"><br>
性别:<input type="text" name="gender"><br>
年龄:<input type="text" name="age"><br>
生日:<input type="text" name="birthday"><br>
爱好:<input type="checkbox" name="hobbyIds" value="1">唱
<input type="checkbox" name="hobbyIds" value="2">跳
<input type="checkbox" name="hobbyIds" value="3">rap<br>
<input type="submit">
</form>
</body>
</html>
Controller
@Controller
@RequestMapping("/user")
public class UserController{
/**
* 第一种接收表单参数的方式:
* 默认日期格式 月/日/年 10/10/2016
* @return
*/
@RequestMapping("/register")
public String register(String username,String password, int age,String gender,Date birthday, String[] hobbyIds){
System.out.println(username);
System.out.println(password);
System.out.println(age);
System.out.println(gender);
System.out.println(birthday);
System.out.println(Arrays.toString(hobbyIds));
return "user/info";
}
}
控制台
张三
123
22
男
Sat Oct 10 00:00:00 CST 2020
[1, 2, 3]
# pojo类型
//模型
public class User {
private Integer id;
private String username;
private String password;
private int age;
private String gender;
private Date birthday;
private String[] hobbyIds;
}
controller
/**
* 第二种接收表单参数的方式:模型方式
* 默认日期格式 月/日/年 10/10/2016
* @return
*/
@RequestMapping("/register")
public String register(User user){
System.out.println(user);
return "user/info";
}
控制台
User{id=null, username='zhangsan', password='123', age=12, gender='男', birthday=Mon Oct 12 00:00:00 CST 2020, hobbyIds=[1, 2, 3]}
# 包装类型
//user的扩展类
public class UserExt {
private User user;
public User getUser() {
return user;
}
public void setUser(User user) {
this.user = user;
}
@Override
public String toString() {
return "UserExt{" +
"user=" + user +
'}';
}
}
jsp
<!-- 表单加上user.-->
<form action="${pageContext.request.contextPath}/user/register.do" method="post">
用户名:<input type="text" name="user.username"><br>
密码:<input type="text" name="user.password"><br>
性别:<input type="text" name="user.gender"><br>
年龄:<input type="text" name="user.age"><br>
生日:<input type="text" name="user.birthday"><br>
爱好:<input type="checkbox" name="user.hobbyIds" value="1">唱
<input type="checkbox" name="user.hobbyIds" value="2">跳
<input type="checkbox" name="user.hobbyIds" value="3">rap<br>
<input type="submit">
</form>
java
@RequestMapping("/register")
public String register(UserExt userExt){
System.out.println(userExt);
return "user/info";
}
控制台
UserExt{user=User{id=null, username='zhangsan', password='123', age=12, gender='男', birthday=Mon Oct 12 00:00:00 CST 2020, hobbyIds=[1, 2, 3]}}
# List类型
public class User {
private String username;
private String password;
}
//扩展类声明list集合
public class UserExt {
//集合类型
private List<User> users;
}
@RequestMapping("/register")
public String register(UserExt userExt){
System.out.println(userExt.getUsers());
return "user/info";
}
<form action="${pageContext.request.contextPath}/user/register.do" method="post">
<!-- private List<User> users -->
用户名1:<input type="text" name="users[0].username"><br>
密码1:<input type="text" name="users[0].password"><br>
=======================================================<br>
用户名2:<input type="text" name="users[1].username"><br>
密码2:<input type="text" name="users[1].password"><br>
<input type="submit">
</form>
控制台
[User{username='张三', password='123'}, User{username='李四', password='456'}]
# Map类型
public class UserExt {
//集合类型
private Map<String,Object> infos = new HashMap<>();
}
@RequestMapping("/register")
public String register(UserExt userExt){
System.out.println(userExt.getInfos());
return "user/info";
}
<form action="${pageContext.request.contextPath}/user/register.do" method="post">
<!-- private Map<String,Object> infos = new HashMap<>() -->
用户名:<input type="text" name="infos['username']"><br>
密码:<input type="text" name="infos['password']"><br>
性别:<input type="text" name="infos['gender']"><br>
年龄:<input type="text" name="infos['age']"><br>
<input type="submit">
</form>
控制台
{username=张三, age=22, gender=男, password=123}
# 数据传递
# 向jsp页面传参
设置数据
@RequestMapping("/list")
public String list(Model model){
//模拟数据库数据
List<User> list = new ArrayList<>();
list.add(new User(1,"张三",15,"男"));
list.add(new User(2,"李四",16,"男"));
list.add(new User(3,"王五",17,"男"));
model.addAttribute("userlist",list);
return "user/userlist";
}
接收数据
<!-- 需要用的el表达式-->
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<html>
<head>
<title>用户列表</title>
</head>
<body>
用户列表界面
<table border="1px">
<tr>
<td>姓名</td>
<td>年龄</td>
<td>性别</td>
<td>修改</td>
</tr>
<c:forEach items="${userlist}" var="user">
<tr>
<td>${user.username}</td>
<td>${user.age}</td>
<td>${user.gender}</td>
<td><a href="${pageContext.request.contextPath}/user/edit.do?id=${user.id}">修改</a></td>
</tr>
</c:forEach>
</table>
</body>
</html>
# parms传参
<a href="${pageContext.request.contextPath}/user/edit?id=${user.id}">
接收参数
@RequestMapping("/edit")
public String edit(Integer id,Model model){
//模拟从数据库取数据
User user = new User(id,"张三",15,"男");
//保存数据宫页面显示
model.addAttribute("user",user);
return "user/edit";
}
# URL传参
<a href="${pageContext.request.contextPath}/user/edit/${user.id}.do">
接收参数
//多个参数@RequestMapping("/edit/{id}/{a}")
//@PathVariable Integer id,@PathVariable Integer a
@RequestMapping("/edit/{id}")
public String edit(@PathVariable Integer id, Model model){
//模拟从数据库取数据
User user = new User(id,"张三",15,"男");
//保存数据宫页面显示
model.addAttribute("user",user);
return "user/edit";
}
# 转发和重定向
# 请求转发
1.转发到同一个控制器的方法
@Controller
@RequestMapping("/user")
public class UserController{
//转发到同一个控制器
@RequestMapping("test")
public String test(){
return "forward:list.do";
}
@RequestMapping("/list")
public String list(Model model){
//省略...
}
}
控制台
http://localhost/springmvc/user/test.do
2.转发到不同一个控制器的方法
//student控制器
@Controller
@RequestMapping("/student")
public class StudentController {
@RequestMapping("test")
public String test(){
return "forward:/user/list.do";
}
}
控制台
http://localhost/springmvc/student/test.do
# 重定向
1.重定向到同一个控制器的方法
@Controller
@RequestMapping("/user")
public class UserController{
//转发到同一个控制器
@RequestMapping("test")
public String test(){
return "redirect:list.do";
}
@RequestMapping("/list")
public String list(Model model){
//省略...
}
}
控制台
http://localhost/springmvc/user/test.do
http://localhost/springmvc/user/list.do
2.重定向到不同一个控制器的方法
//student控制器
@Controller
@RequestMapping("/student")
public class StudentController {
@RequestMapping("test")
public String test(){
return "redirect:/user/list.do";
}
}
控制台
http://localhost/springmvc/student/test.do
http://localhost/springmvc/user/list.do
# 返回json数据
1.导入jackson-core和jackson-mapper
2.在springMVC的配置文件中开启MVC驱动
3.在处理ajax请求的方法上加上注解@ResponseBody
4.将要转换为json且响应到客户端的数据，直接作为该方法返回值返回
实例
//@RequestBody 请求数据转成对象
//@ResponseBody 响应数据转成json
@RequestMapping("register")
@ResponseBody
public String Student save(){
return "你好";
}