springmvc概述和入门案例
创建工程
可能在网上下载了一些乱七八糟的东西，解决创建项目过慢的问题
~~~~
创建resources下的springmvc.xml
xmlns:mvc="http://www.springframework.org/schema/mvc"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="
http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/mvc
http://www.springframework.org/schema/mvc/spring-mvc.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context.xsd">
webapp下创建web.xml
"-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"
"http://java.sun.com/dtd/web-app_2_3.dtd" >
dispatcherServlet
org.springframework.web.servlet.DispatcherServlet
contextConfigLocation
classpath:springmvc.xml
1
dispatcherServlet
/
characterEncodingFilter
org.springframework.web.filter.CharacterEncodingFilter
encoding
UTF-8
characterEncodingFilter
/* RequestMapping注解
package org.springframework.web.bind.annotation;
import java.lang.annotation.Documented;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
import org.springframework.core.annotation.AliasFor;
@Target({ElementType.METHOD, ElementType.TYPE})
@Retention(RetentionPolicy.RUNTIME)
@Documented
@Mapping
public @interface RequestMapping {
String name() default "";
@AliasFor("path")
String[] value() default {};
@AliasFor("value")//别名
String[] path() default {};
RequestMethod[] method() default {};
String[] params() default {};
String[] headers() default {};
String[] consumes() default {};
String[] produces() default {};}
path和value是一样的
@RequestMapping(path="/user")
@RequestMapping(value="/user")
@RequestMapping("/user")
RequestMethod
public enum RequestMethod {
GET,
HEAD,
POST,
PUT,
PATCH,
DELETE,
OPTIONS,
TRACE;
private RequestMethod() {
}}
因为是枚举的类型,可以取的值
method={RequestMethod.POST,RequestMethod.GET}
params讲解
参数绑定和自定义类型转换
1 入门
<%--
Created by IntelliJ IDEA.
User: Administrator
Date: 2018/4/29
Time: 22:10
To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
Title <%--请求参数绑定--%>
<%--
请求参数绑定
把数据封装Account类中
--%>
<%--把数据封装Account类中，类中存在list和map的集合
--%>
<%--自定义类型转换器
--%>
Servlet原生的API
2 请求参数绑定实体类
3 解决中文乱码
"-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"
"http://java.sun.com/dtd/web-app_2_3.dtd" >
dispatcherServlet
org.springframework.web.servlet.DispatcherServlet
contextConfigLocation
classpath:springmvc.xml
1
dispatcherServlet
/
characterEncodingFilter
org.springframework.web.filter.CharacterEncodingFilter
encoding
UTF-8
characterEncodingFilter
/* 4 请求参数绑定集合类型
<%--请求参数绑定--%>
<%--
请求参数绑定
把数据封装Account类中
--%>
<%--把数据封装Account类中，类中存在list和map的集合
--%>表单提交后
package cn.itcast.controller;
import cn.itcast.domain.Account;
import cn.itcast.domain.User;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import javax.servlet.ServletContext;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
/**
- 请求参数绑定
*/
@Controller
@RequestMapping("/param")
public class ParamController {
/**
* 请求参数绑定入门
* @return
*/
@RequestMapping("/testParam")
public String testParam(String username,String password){
System.out.println("执行了...");
System.out.println("用户名："+username);
System.out.println("密码："+password);
return "success";
}
/**
* 请求参数绑定把数据封装到JavaBean的类中
* @return
*/
@RequestMapping("/saveAccount")
public String saveAccount(Account account){
System.out.println("执行了...");
System.out.println(account);
return "success";
}
/**
* 自定义类型转换器
* @param user
* @return
*/
@RequestMapping("/saveUser")
public String saveUser(User user){
System.out.println("执行了...");
System.out.println(user);
return "success";
}
/**
* 原生的API
* @return
*/
@RequestMapping("/testServlet")
public String testServlet(HttpServletRequest request, HttpServletResponse response){
System.out.println("执行了...");
System.out.println(request);
HttpSession session = request.getSession();
System.out.println(session);
ServletContext servletContext = session.getServletContext();
System.out.println(servletContext);
System.out.println(response);
return "success";
}
}
package cn.itcast.domain;
import java.io.Serializable;
import java.util.List;
import java.util.Map;
public class Account implements Serializable{
private String username;
private String password;
private Double money;
// private User user;
private List list;
private Map map;
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
public Double getMoney() {
return money;
}
public void setMoney(Double money) {
this.money = money;
}
public List getList() {
return list;
}
public void setList(List list) {
this.list = list;
}
public Map getMap() {
return map;
}
public void setMap(Map map) {
this.map = map;
}
/*
public User getUser() {
return user;
}
public void setUser(User user) {
this.user = user;
} */
@Override
public String toString() {
return "Account{" +
"username='" + username + '\'' +
", password='" + password + '\'' +
", money=" + money +
", list=" + list +
", map=" + map +
'}';
}}
package cn.itcast.domain;
import java.io.Serializable;
import java.util.Date;
public class User implements Serializable{
private String uname;
private Integer age;
private Date date;
public String getUname() {
return uname;
}
public void setUname(String uname) {
this.uname = uname;
}
public Integer getAge() {
return age;
}
public void setAge(Integer age) {
this.age = age;
}
public Date getDate() {
return date;
}
public void setDate(Date date) {
this.date = date;
}
@Override
public String toString() {
return "User{" +
"uname='" + uname + '\'' +
", age=" + age +
", date=" + date +
'}';
}}
5 自定义类型转换器演示异常
6 自定义转换器代码的编写
例如2019-11-11这样日期格式就不行,必须是2020/12/07这样的格式，所以需要自定义转换
必须实现Converter
ctrl键一直按找类或者接口的源码
springmvc.xml的配置文件
编写自定义转换的类
package cn.itcast.utils;
import org.springframework.core.convert.converter.Converter;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Date;
/**
- 把字符串转换日期
*/
public class StringToDateConverter implements Converter
/**
* String source 传入进来字符串
* @param source
* @return
*/
public Date convert(String source) {
// 判断
if(source == null){
throw new RuntimeException("请您传入数据");
}
DateFormat df = new SimpleDateFormat("yyyy-MM-dd");
try {
// 把字符串转换日期
//返回值java.util.Date的类型
return df.parse(source);
} catch (Exception e) {
throw new RuntimeException("数据类型转换出现错误");
}
}
}
表单提交
提交后控制台打印的数据
Student{username='李四', age=12, birthday=Sun Mar 22 00:00:00 CST 2020}
7 获取Servlet原生的API~~~~
@RequestMapping("/testServlet")
public String testServlet(HttpServletRequest request, HttpServletResponse response){
System.out.println("执行了...");
System.out.println(request);
HttpSession session = request.getSession();
System.out.println(session);
ServletContext servletContext = session.getServletContext();
System.out.println(servletContext);
System.out.println(response);
return "success";
}
Spring MVC的常用注解
1 RequestParam注解
2 RequestBody注解
3 PathVariable注解
4 HiddentHttpMethodFilter过滤器
5 RequestHeader注解
6 CookieValue注解
7 ModelAttribute注解
8 SessionAttributes注解
/**
* SessionAttributes的注解
* @return
*/
@RequestMapping(value="/testSessionAttributes")
public String testSessionAttributes(Model model){
System.out.println("testSessionAttributes...");
// 底层会存储到request域对象中
model.addAttribute("msg","美美");
return "success";
}
/**
* 获取值获取的时候必须填写Model的实现类ModelMap
* @param modelMap
* @return
*/
@RequestMapping(value="/getSessionAttributes")
public String getSessionAttributes(ModelMap modelMap){
System.out.println("getSessionAttributes...");
String msg = (String) modelMap.get("msg");
System.out.println(msg);
return "success";
}
/**
* 清除
* @param status
* @return
*/
@RequestMapping(value="/delSessionAttributes")
public String delSessionAttributes(SessionStatus status){
System.out.println("getSessionAttributes...");
status.setComplete();
return "success";
}