SpringMVC学习笔记之---数据绑定

SpringMVC数据绑定

一.基础配置

（1）pom.xml

<dependencies>
  <dependency>
    <groupId>junit</groupId>
    <artifactId>junit</artifactId>
    <version>4.11</version>
  </dependency>
  <dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-webmvc</artifactId>
    <version>5.1.3.RELEASE</version>
  </dependency>
  <dependency>
    <groupId>javax.servlet</groupId>
    <artifactId>javax.servlet-api</artifactId>
    <version>3.1.0</version>
  </dependency>
  <!-- https://mvnrepository.com/artifact/javax.servlet/jstl -->
  <dependency>
    <groupId>javax.servlet</groupId>
    <artifactId>jstl</artifactId>
    <version>1.2</version>
  </dependency>
  </dependencies>

（2）web.xml

<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.xml</param-value>

  </init-param>

</servlet>

<servlet-mapping>

  <servlet-name>SpringMVC</servlet-name>

  <url-pattern>/</url-pattern>

</servlet-mapping>

（3）springmvc.xml

<?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.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd">

    <!--配置包扫描-->

    <context:component-scan base-package="controller,dao"></context:component-scan>

    <!--配置视图解析器-->

    <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">

        <!--配置前缀-->

        <property name="prefix" value="/"></property>

        <!--配置后缀-->

        <property name="suffix" value=".jsp"></property>

    </bean>

    <!--消息转换器-->

    <mvc:annotation-driven>

        <mvc:message-converters>

            <bean class="org.springframework.http.converter.json.MappingJackson2HttpMessageConverter"></bean>

        </mvc:message-converters>

    </mvc:annotation-driven>

</beans>

（4）Course.java（实体类）

package entity;



public class Course {

    private int id;

    private String name;

    private double price;

    private Author author;



    public int getId() {

        return id;

    }



    public void setId(int id) {

        this.id = id;

    }



    public String getName() {

        return name;

    }



    public void setName(String name) {

        this.name = name;

    }



    public double getPrice() {

        return price;

    }



    public void setPrice(double price) {

        this.price = price;

    }



    public Author getAuthor() {

        return author;

    }



    public void setAuthor(Author author) {

        this.author = author;

    }



    @Override

    public String toString() {

        return "Course{" +

                "id=" + id +

                ", name='" + name + '\'' +

                ", price=" + price +

                ", author=" + author +

                '}';

    }

}

（5）Author.java（实体类）

package entity;



public class Author {

    private int id;

    private String name;



    public int getId() {

        return id;

    }



    public void setId(int id) {

        this.id = id;

    }



    public String getName() {

        return name;

    }



    public void setName(String name) {

        this.name = name;

    }

}

（6）SaveDao.java（用于保存的dao）

package dao;



import entity.Course;

import org.springframework.stereotype.Repository;



import java.util.Collection;

import java.util.HashMap;

import java.util.Map;



@Repository

public class SaveDao {

   private Map<Integer,Course> map=new HashMap<Integer, Course>();

   public void save(Course course){

       map.put(course.getId(),course);

   }

   public Collection<Course> getall(){

       return map.values();

   }

}

（7）index.jsp（用于遍历显示）

<%@ page contentType="text/html;charset=UTF-8" language="java" %>

<%@page isELIgnored="false" %>

<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>

<html>

<head>

    <title>Title</title>

</head>

<body>

<table>

    <tr>

        <td>课程ID</td>

        <td>课程名</td>

        <td>课程价格</td>

        <td>讲师ID</td>

        <td>讲师名</td>

    </tr>

    <c:forEach items="${courses}" var="course">

        <tr>

            <td>${course.id}</td>

            <td>${course.name}</td>

            <td>${course.price}</td>

            <td>${course.author.id}</td>

            <td>${course.author.name}</td>

        </tr>

    </c:forEach>

</table>



</body>

</html>

二.数据绑定分类

（一）普通数据类型的数据绑定

（二）包装类的数据绑定

（三）数组类型的数据绑定

（四）对象类型的数据绑定

（五）List集合类型的数据绑定

（六）Map集合类型的数据绑定

（七）Set集合类型的数据绑定

 DataController.java

package controller;



import dao.SaveDao;

import entity.*;

import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.stereotype.Controller;

import org.springframework.web.bind.annotation.RequestBody;

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

import org.springframework.web.bind.annotation.RequestParam;

import org.springframework.web.bind.annotation.ResponseBody;

import org.springframework.web.servlet.ModelAndView;



@Controller

public class DataController {

    @Autowired

    private SaveDao saveDao;

    /**

     * 基本数据类型的数据绑定

     * @param id

     * @return

     */

    @RequestMapping("/one")

    @ResponseBody  //将返回值显示到页面

    public String one(@RequestParam(value="id") int id){

        return "id:"+id;

    }



    /**

     * 包装类的数据绑定

     * @param id

     * @return

     */

    @RequestMapping("/two")

    @ResponseBody

    public String two(@RequestParam(value="id")Integer id){

        return "id"+id;

    }



    /**

     * 数组类型的数据绑定

     * @param three

     * @return

     */

    @RequestMapping("/three")

    @ResponseBody

    public String three(String[] three){

       StringBuffer st=new StringBuffer();

       for(String s:three){

           st.append(s).append(" ");

       }

       return st.toString();

    }



    /**

     * 对象类型的数据绑定

     * 对象保存，在dao层进行

     * @param course

     * @return

     */

    @RequestMapping("/four")

    public ModelAndView four(Course course){

        saveDao.save(course);

        ModelAndView modelAndView=new ModelAndView();

        modelAndView.setViewName("index");

        modelAndView.addObject("courses",saveDao.getall());

        return modelAndView;

    }



    /**

     * List集合类型的数据绑定

     * 不能直接绑定集合，应该创建一个包装类

     * @param courceList

     * @return

     */

    @RequestMapping("/five")

    public ModelAndView five(CourceList courceList){

        for(Course course:courceList.getCourses()){

            saveDao.save(course);



        }

        ModelAndView modelAndView=new ModelAndView();

        modelAndView.setViewName("index");

        modelAndView.addObject("courses",saveDao.getall());

        return modelAndView;

    }



    /**

     * Map集合类型的数据绑定

     * @param courseMap

     * @return

     */

    @RequestMapping("/six")

    public ModelAndView six(CourseMap courseMap){

        for(Course course:courseMap.getMap().values()){

            System.out.println(course);

            saveDao.save(course);

        }

        ModelAndView modelAndView=new ModelAndView();

        modelAndView.setViewName("index");

        modelAndView.addObject("courses",saveDao.getall());

        return modelAndView;

    }



    /**

     * Set集合类型的数据绑定

     * @param courseSet

     * @return

     */

    @RequestMapping("/seven")

    public ModelAndView seven(CourseSet courseSet){

        for(Course course:courseSet.getSet()){

            saveDao.save(course);

        }

        ModelAndView modelAndView=new ModelAndView();

        modelAndView.setViewName("index");

        modelAndView.addObject("courses",saveDao.getall());

        return modelAndView;

    }

    @RequestMapping(value="/eight")

    @ResponseBody

    public String eight(@RequestBody User user){

        user.setName("成功");

        System.out.println("==========");

        return "aa";

    }



}

三.数据绑定所需的类和页面

（一）普通数据类型

（二）包装类

（三）数组类型

（四）对象类型

1.save.jsp

<%@ page contentType="text/html;charset=UTF-8" language="java" %>

<html>

<head>

    <title>Title</title>

</head>

<body>

<form action="/four" method="post">

    课程ID：<input type="text" name="id">

    课程名：<input type="text" name="name">

    课程价格：<input type="text" name="12.5">

    讲师ID：<input type="text" name="author.id">

    讲师名：<input type="text" name="author.name">

    <input type="submit">

</form>

</body>

</html>

（五）List集合

1.CourseList.java

package entity;



import java.util.List;



public class CourceList {

    private List<Course> courses;



    public List<Course> getCourses() {

        return courses;

    }



    public void setCourses(List<Course> courses) {

        this.courses = courses;

    }

}

2.saveList.jsp

<%@ page contentType="text/html;charset=UTF-8" language="java" %>

<html>

<head>

    <title>Title</title>

</head>

<body>

<form action="/five" method="post">

    课程1ID：<input type="text" name="courses[0].id">

    课程1名：<input type="text" name="courses[0].name">

    课程1价格：<input type="text" name="courses[0].price">

    讲师1ID：<input type="text" name="courses[0].author.id">

    讲师1名：<input type="text" name="courses[0].author.name">

    课程2ID：<input type="text" name="courses[1].id">

    课程2名：<input type="text" name="courses[1].name">

    课程2价格：<input type="text" name="courses[1].price">

    讲师2ID：<input type="text" name="courses[1].author.id">

    讲师2名：<input type="text" name="courses[1].author.name">

    <input type="submit">

</form>

</body>

</html>

（六）Map集合

1.CourseMap.java

package entity;



import java.util.Map;



public class CourseMap {

    private Map<String,Course> map;



    public Map<String, Course> getMap() {

        return map;

    }



    public void setMap(Map<String, Course> map) {

        this.map = map;

    }



    @Override

    public String toString() {

        return "CourseMap{" +

                "map=" + map +

                '}';

    }

}

2.saveMap.jsp

<%@ page contentType="text/html;charset=UTF-8" language="java" %>

<html>

<head>

    <title>Title</title>

</head>

<body>

<form action="/six" method="post">

    课程1ID：<input type="text" name="map['one'].id">

    课程1名：<input type="text" name="map['one'].name">

    课程1价格：<input type="text" name="map['one'].price">

    讲师1ID：<input type="text" name="map['one'].author.id">

    讲师1名：<input type="text" name="map['one'].author.name">

    课程2ID：<input type="text" name="map['two'].id">

    课程2名：<input type="text" name="map['two'].name">

    课程2价格：<input type="text" name="map['two'].price">

    讲师2ID：<input type="text" name="map['two'].author.id">

    讲师2名：<input type="text" name="map['two'].author.name">

    <input type="submit">

</form>

</body>

</html>

（七）Set集合

1.CourseSet.java

package entity;



import java.util.HashSet;

import java.util.Set;



public class CourseSet {

    private Set<Course> set=new HashSet<Course>();



    public Set<Course> getSet() {

        return set;

    }



    public void setSet(Set<Course> set) {

        this.set = set;

    }

    public CourseSet(){

        set.add(new Course());

        set.add(new Course());

    }

}

2.saveSet.jsp

<%@ page contentType="text/html;charset=UTF-8" language="java" %>

<html>

<head>

    <title>Title</title>

</head>

<body>

<form action="/seven" method="post">

    课程1ID：<input type="text" name="set[0].id">

    课程1名：<input type="text" name="set[0].name">

    课程1价格：<input type="text" name="set[0].price">

    讲师1ID：<input type="text" name="set[0].author.id">

    讲师1名：<input type="text" name="set[0].author.name">

    课程2ID：<input type="text" name="set[1].id">

    课程2名：<input type="text" name="set[1].name">

    课程2价格：<input type="text" name="set[1].price">

    讲师2ID：<input type="text" name="set[1].author.id">

    讲师2名：<input type="text" name="set[1].author.name">

    <input type="submit">

</form>

</body>

</html>

-----------------------------------demo12------------------------------------