24_01SpringMVC

1.MVC模型

2.SpringMVC概述 

2.1SpringMVC是什么

2.2SpringMVC在三层架构的位置

2.3SpringMVC的优势

2.4SpringMVC和Struts2的优略分析

3.SpringMVC的入门程序

3.1需求

3.2创建WEB工程，引入开发的jar包

<?xml version="1.0" encoding="UTF-8"?>

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>cn.itcast</groupId>
    <artifactId>springmvc_day01_01start</artifactId>
    <version>1.0-SNAPSHOT</version>
    <packaging>war</packaging>

    <name>springmvc_day01_01start Maven Webapp</name>
    <!-- FIXME change it to the project's website -->
    <url>http://www.example.com</url>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <maven.compiler.source>1.8</maven.compiler.source>
        <maven.compiler.target>1.8</maven.compiler.target>
        <spring.version>5.0.2.RELEASE</spring.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>${spring.version}</version>
        </dependency>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-web</artifactId>
            <version>${spring.version}</version>
        </dependency>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>${spring.version}</version>
        </dependency>

        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>servlet-api</artifactId>
            <version>2.5</version>
            <scope>provided</scope>
        </dependency>

        <dependency>
            <groupId>javax.servlet.jsp</groupId>
            <artifactId>jsp-api</artifactId>
            <version>2.0</version>
            <scope>provided</scope>
        </dependency>

    </dependencies>

    <build>
        <finalName>springmvc_day01_01start</finalName>
        <pluginManagement><!-- lock down plugins versions to avoid using Maven defaults (may be moved to parent pom) -->
            <plugins>
                <plugin>
                    <artifactId>maven-clean-plugin</artifactId>
                    <version>3.1.0</version>
                </plugin>
                <!-- see http://maven.apache.org/ref/current/maven-core/default-bindings.html#Plugin_bindings_for_war_packaging -->
                <plugin>
                    <artifactId>maven-resources-plugin</artifactId>
                    <version>3.0.2</version>
                </plugin>
                <plugin>
                    <artifactId>maven-compiler-plugin</artifactId>
                    <version>3.8.0</version>
                </plugin>
                <plugin>
                    <artifactId>maven-surefire-plugin</artifactId>
                    <version>2.22.1</version>
                </plugin>
                <plugin>
                    <artifactId>maven-war-plugin</artifactId>
                    <version>3.2.2</version>
                </plugin>
                <plugin>
                    <artifactId>maven-install-plugin</artifactId>
                    <version>2.5.2</version>
                </plugin>
                <plugin>
                    <artifactId>maven-deploy-plugin</artifactId>
                    <version>2.8.2</version>
                </plugin>
            </plugins>
        </pluginManagement>
    </build>
</project>

3.3 配置核心的控制器（配置DispatcherServlet）

在web.xml配置文件中核心控制器DispatcherServlet

<!DOCTYPE web-app PUBLIC
 "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"
 "http://java.sun.com/dtd/web-app_2_3.dtd" >

<web-app>
  <display-name>Archetype Created Web Application</display-name>

  <!--配置前端控制器-->
  <servlet>
    <servlet-name>dispatcherServlet</servlet-name>
    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
    <init-param>
      <param-name>contextConfigLocation</param-name>
      <param-value>classpath:springmvc.xml</param-value>
    </init-param>
    <load-on-startup>1</load-on-startup>
  </servlet>
  <servlet-mapping>
    <servlet-name>dispatcherServlet</servlet-name>
    <url-pattern>/</url-pattern>
  </servlet-mapping>
</web-app>

3.4编写springmvc.xml的配置文件

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       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">

    <!-- 开启注解扫描 -->
    <context:component-scan base-package="cn.itcast"/>

    <!-- 视图解析器对象 -->
    <bean id="internalResourceViewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="prefix" value="/WEB-INF/pages/"/>
        <property name="suffix" value=".jsp"/>
    </bean>

    <!-- 开启SpringMVC框架注解的支持 -->
    <mvc:annotation-driven />
</beans>

3.5编写index.jsp和HelloController控制器类

<%--
  Created by IntelliJ IDEA.
  User: Administrator
  Date: 2019/12/31
  Time: 20:35
  To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>Title</title>
</head>
<body>

<h3>入门程序</h3>
<a href="hello">入门程序</a>
</body>
</html>

package cn.itcast.controller;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;

//控制器类
@Controller
public class HelloController {
    @RequestMapping(path="/hello")
    public String sayHello(){
        System.out.println("hello springMVC");
        return  "success";
    }
}

3.6在WEB-INF目录下创建pages文件夹，编写success.jsp的成功页面

<%--
  Created by IntelliJ IDEA.
  User: Administrator
  Date: 2019/12/31
  Time: 20:46
  To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>Title</title>
</head>
<body>
<h3>入门成功了</h3>
</body>
</html>

 

4.入门案例中涉及的组件

4.1DispatcherServlet：前端控制器

4.2HandlerMapping：处理器映射器

4.3Handler

4.4HandlAdapter：处理器适配器

4.5View Resolver：视图解析器

4.6View：视图

4.7<mvc:annotation-driven> 说明

5.RequestMapping 注解

5.1出现位置

1.方法上

2.类上

跳转路径必须是user/*，否则报错。

5.2属性

 

6.请求参数的绑定

6.1请求参数的机制

　　1. 表单提交的数据都是k=v格式的 username=haha&password=123
　　2. SpringMVC的参数绑定过程是把表单提交的请求参数，作为控制器中方法的参数进行绑定的
　　3. 要求：提交表单的name和参数的名称是相同的

<%--
  Created by IntelliJ IDEA.
  User: Administrator
  Date: 2020/1/2
  Time: 9:44
  To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>Title</title>
</head>
<body>
<%--请求参数绑定--%>
<a href="param/testParam?username=hehe&password=123">请求参数绑定</a>


</body>
</html>

package cn.itcast.controller;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;

/**
 * 请求参数绑定
 */
@Controller
@RequestMapping("/param")
public class ParamController {
    /**
     * 请求参数绑定的入门
     *
     * @return
     */
    @RequestMapping("/testParam")
    public String testParam(String username, String password) {
        System.out.println("执行了...");
        System.out.println("username:" + username);
        System.out.println("password:" + password);
        return "success";
    }
}

6.2 支持的数据类型

实体类型

<%--
  Created by IntelliJ IDEA.
  User: Administrator
  Date: 2020/1/2
  Time: 9:44
  To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>Title</title>
</head>
<body>

<%--把数据封装Account类中--%>
<form action="param/saveAccount" method="post">
    姓名：<input type="text" name="username" /><br/>
    密码：<input type="text" name="password" /><br/>
    金额：<input type="text" name="money" /><br/>
    <input type="submit" value="提交" />
</form>

</body>
</html>

package cn.itcast.controller;

import cn.itcast.domain.Account;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;

/**
 * 请求参数绑定
 */
@Controller
@RequestMapping("/param")
public class ParamController {
    /**
     * 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";
    }
}

实体类中包含引用类型

package cn.itcast.domain;

import java.io.Serializable;
import java.util.Date;

public class User implements Serializable {

    private String uname;
    private Integer age;


    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;
    }


    @Override
    public String toString() {
        return "User{" +
                "uname='" + uname + '\'' +
                ", age=" + age +
                '}';
    }
}

package cn.itcast.domain;

import java.io.Serializable;

public class Account implements Serializable{

    private String username;
    private String password;
    private Double money;

     private User user;


    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 User getUser() {
        return user;
    }

    public void setUser(User user) {
        this.user = user;
    }

    @Override
    public String toString() {
        return "Account{" +
                "username='" + username + '\'' +
                ", password='" + password + '\'' +
                ", money=" + money +
                ", user=" + user +
                '}';
    }
}

package cn.itcast.controller;

import cn.itcast.domain.Account;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;

/**
 * 请求参数绑定
 */
@Controller
@RequestMapping("/param")
public class ParamController {
    /**
     * 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";
    }
}

<%--
  Created by IntelliJ IDEA.
  User: Administrator
  Date: 2020/1/2
  Time: 9:44
  To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>Title</title>
</head>
<body>

<%--把数据封装Account类中--%>
<form action="param/saveAccount" method="post">
    姓名：<input type="text" name="username" /><br/>
    密码：<input type="text" name="password" /><br/>
    金额：<input type="text" name="money" /><br/>
    用户姓名：<input type="text" name="user.uname" /><br/>
    用户年龄：<input type="text" name="user.age" /><br/>
    <input type="submit" value="提交" />
</form>

</body>
</html>

 

请求参数中文乱码的解决

在web.xml中添加一个过滤器

<!DOCTYPE web-app PUBLIC
        "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"
        "http://java.sun.com/dtd/web-app_2_3.dtd" >

<web-app>
  <display-name>Archetype Created Web Application</display-name>

  <!--配置前端控制器-->
  <servlet>
    <servlet-name>dispatcherServlet</servlet-name>
    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
    <init-param>
      <param-name>contextConfigLocation</param-name>
      <param-value>classpath:springmvc.xml</param-value>
    </init-param>
    <load-on-startup>1</load-on-startup>
  </servlet>
  <servlet-mapping>
    <servlet-name>dispatcherServlet</servlet-name>
    <url-pattern>/</url-pattern>
  </servlet-mapping>

  <!--配置解决中文乱码的过滤器-->
  <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>

</web-app>

 

  

 实体类中包含集合数据类型

package cn.itcast.domain;

import java.io.Serializable;
import java.util.Date;

public class User implements Serializable {

    private String uname;
    private Integer age;


    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;
    }


    @Override
    public String toString() {
        return "User{" +
                "uname='" + uname + '\'' +
                ", age=" + age +
                '}';
    }
}

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 List<User> list;
    private Map<String, User> 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<User> getList() {
        return list;
    }

    public void setList(List<User> list) {
        this.list = list;
    }

    public Map<String, User> getMap() {
        return map;
    }

    public void setMap(Map<String, User> map) {
        this.map = map;
    }


    @Override
    public String toString() {
        return "Account{" +
                "username='" + username + '\'' +
                ", password='" + password + '\'' +
                ", money=" + money +
                ", list=" + list +
                ", map=" + map +
                '}';
    }
}

package cn.itcast.controller;

import cn.itcast.domain.Account;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;

/**
 * 请求参数绑定
 */
@Controller
@RequestMapping("/param")
public class ParamController {
    /**
     * 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";
    }
}

<%--
  Created by IntelliJ IDEA.
  User: Administrator
  Date: 2020/1/2
  Time: 9:44
  To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>Title</title>
</head>
<body>

<%--把数据封装Account类中,类中存在list和map集合--%>
<form action="param/saveAccount" method="post">
    姓名：<input type="text" name="username" /><br/>
    密码：<input type="text" name="password" /><br/>
    金额：<input type="text" name="money" /><br/>

    用户姓名：<input type="text" name="list[0].uname" /><br/>
    用户年龄：<input type="text" name="list[0].age" /><br/>

    用户姓名：<input type="text" name="map['one'].uname" /><br/>
    用户年龄：<input type="text" name="map['one'].age" /><br/>
    <input type="submit" value="提交" />
</form>

</body>
</html>

 

7.自定义类型转换器

7.1使用场景

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 +
                '}';
    }
}

<%--
  Created by IntelliJ IDEA.
  User: Administrator
  Date: 2020/1/2
  Time: 9:44
  To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>Title</title>
</head>
<body>

<%--自定义类型转换器--%>
<form action="/param/saveUser" method="post">

    用户姓名：<input type="text" name="uname" /><br/>
    用户年龄：<input type="text" name="age" /><br/>
    用户生日：<input type="text" name="date" /><br/>

    <input type="submit" value="提交" />
</form>

</body>
</html>

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;

/**
 * 请求参数绑定
 */
@Controller
@RequestMapping("/param")
public class ParamController {
    /**
     * 自定义类型转换器
     *
     * @return
     */
    @RequestMapping("/saveUser")
    public String saveUser(User user) {
        System.out.println("执行了...");
        System.out.println(user);
        return "success";
    }
}

 

 但是输入的日期格式如果是这样，则提示错误：

7.2解决方法

1.自定义类型转换器

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, Date> {

    /**
     *
     * @param source : 传入进来字符串
     * @return
     */
    @Override
    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
            return df.parse(source);
        } catch (Exception e) {
            throw new RuntimeException("数据类型转换出现错误");
        }
    }
}

2.在 springmvc.xml配置文件中配置类型转换器

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       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">

    <!-- 开启注解扫描 -->
    <context:component-scan base-package="cn.itcast"/>

    <!-- 视图解析器对象 -->
    <bean id="internalResourceViewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="prefix" value="/WEB-INF/pages/"/>
        <property name="suffix" value=".jsp"/>
    </bean>

    <!--配置自定义类型转换器-->
    <bean id="conversionService" class="org.springframework.context.support.ConversionServiceFactoryBean">
        <property name="converters">
            <set>
                <bean class="cn.itcast.utils.StringToDateConverter"/>
            </set>
        </property>
    </bean>
    <!-- 开启SpringMVC框架注解的支持 -->
    <mvc:annotation-driven conversion-service="conversionService"/> <!-- 在 annotation-driven  标签中引用配置的类型转换服务-->
</beans>

运行成功