SpringMVC 表单标签进行数据绑定(图书管理实战)

分手后的思念是犯贱 2022-05-23 03:53 162阅读 0赞

> 该篇博客主要通过一个项目Demo来演绎利用SpringMVC的表单标签进行数据绑定的过程

### 一、场景 ###

*  书籍的添加
 *  书籍信息的修改
 *  所有书籍的显示功能

--------------------

### 二、场景分析 ###

通过SpringMVC的表单标签进行数据绑定

##### 1、实体类 #####

Book类(书籍类)  
Category类(书籍类别类)

##### 2、控制器 #####

BookController：允许用户创建新书籍、修改书籍信息、并列出所有书籍

BookController依赖BookService进行一些后台处理

##### 3、Service类 #####

IBookService接口和其实现类

BookServiceImpl类包含一个Book对象的List和一个Category对象的List。这两个List都是在实例化类时生成的。这个类包含了获取所有书籍、获得单个书籍、添加和更新书籍方法

##### 4、配置文件 #####

*  web.xml配置DispatcherServlet
 *  springmvc配置文件配置(1.扫描包、2.配置视图解析器）

##### 5、view视图 #####

*  修改页面
 *  添加页面
 *  显示所有书籍页面

--------------------

### 三、解决方案 ###

#### 1、项目目录 ####

![这里写图片描述][70]

#### 2、实体类(Book、Category) ####

##### Book.java #####

package com.linjie.pojo;
    
    import java.io.Serializable;
    
    /**
    * @author 浅然    xulinjie0105@gmail.com
    * @version 创建时间：2018年5月31日 下午2:10:08
    * Book实体类
    */
    public class Book implements Serializable {
        private static final long serialVersionUID = 1L;
        private long id;            //书的id
        private String isbn;        //书的目录
        private String title;       //书的标题
        private Category category;  //书的类别
        private String author;      //书的作者
    
        public Book() {}
        public Book(long id, String isbn, String title, Category category, String author) {
            super();
            this.id = id;
            this.isbn = isbn;
            this.title = title;
            this.category = category;
            this.author = author;
        }
        /**
         * @return the id
         */
        public long getId() {
            return id;
        }
        /**
         * @param id the id to set
         */
        public void setId(long id) {
            this.id = id;
        }
        /**
         * @return the isbn
         */
        public String getIsbn() {
            return isbn;
        }
        /**
         * @param isbn the isbn to set
         */
        public void setIsbn(String isbn) {
            this.isbn = isbn;
        }
        /**
         * @return the title
         */
        public String getTitle() {
            return title;
        }
        /**
         * @param title the title to set
         */
        public void setTitle(String title) {
            this.title = title;
        }
        /**
         * @return the category
         */
        public Category getCategory() {
            return category;
        }
        /**
         * @param category the category to set
         */
        public void setCategory(Category category) {
            this.category = category;
        }
        /**
         * @return the author
         */
        public String getAuthor() {
            return author;
        }
        /**
         * @param author the author to set
         */
        public void setAuthor(String author) {
            this.author = author;
        }
        /**
         * @return the serialversionuid
         */
        public static long getSerialversionuid() {
            return serialVersionUID;
        }
    
        /* (non-Javadoc)
         * @see java.lang.Object#toString()
         */
        @Override
        public String toString() {
            return "Book [id=" + id + ", isbn=" + isbn + ", title=" + title + ", category=" + category + ", author="
                    + author + "]";
        }
    }

##### Category.java #####

package com.linjie.pojo;
    
    import java.io.Serializable;
    
    /**
    * @author 浅然    xulinjie0105@gmail.com
    * @version 创建时间：2018年5月31日 下午2:13:04
    * 类别实体类
    */
    public class Category implements Serializable{
        private static final long serialVersionUID = 1L;
        private int id;         //类别的id
        private String name;    //类别的名称
    
        public Category() {}
        public Category(int id, String name) {
            super();
            this.id = id;
            this.name = name;
        }
        /**
         * @return the id
         */
        public int getId() {
            return id;
        }
        /**
         * @param id the id to set
         */
        public void setId(int id) {
            this.id = id;
        }
        /**
         * @return the name
         */
        public String getName() {
            return name;
        }
        /**
         * @param name the name to set
         */
        public void setName(String name) {
            this.name = name;
        }
        /**
         * @return the serialversionuid
         */
        public static long getSerialversionuid() {
            return serialVersionUID;
        }
    
        /* (non-Javadoc)
         * @see java.lang.Object#toString()
         */
        @Override
        public String toString() {
            return "Category [id=" + id + ", name=" + name + "]";
        }
    }

#### 3、控制器(Controller) ####

##### BookController.java #####

> 注意：BookController依赖BookService进行一些后台处理,需要利用@Autowired标注用于给BookController注入一个IBookService实现
> 
> @Autowired(required=true)
> 
> private IBookService iBookService;

package com.linjie.controller;
    
    import java.util.List;
    
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.stereotype.Controller;
    import org.springframework.ui.Model;
    import org.springframework.web.bind.annotation.ModelAttribute;
    import org.springframework.web.bind.annotation.PathVariable;
    import org.springframework.web.bind.annotation.RequestMapping;
    
    import com.linjie.pojo.Book;
    import com.linjie.pojo.Category;
    import com.linjie.service.IBookService;
    
    /**
    * @author 浅然    xulinjie0105@gmail.com
    * @version 创建时间：2018年5月31日 下午2:20:33
    * 控制器
    * 添加书、修改书、保存书、更新书、列出所有书
    */
    @Controller
    public class BookController {
    
        @Autowired(required=true)
        private IBookService iBookService;
    
        //添加书
        @RequestMapping(value = "/book_input")
        public String inputBook(Model model) {
            List<Category> categories = iBookService.getAllCategories();
            model.addAttribute("categories", categories);
            model.addAttribute("book",new Book());
            return "BookAddForm";
        }
    
        //修改书
        @RequestMapping(value = "/book_edit/{id}")
        public String editBook(Model model,@PathVariable long id) {
            List<Category> categories = iBookService.getAllCategories();
            model.addAttribute("categories",categories);
            Book book = iBookService.get(id);
            model.addAttribute("book",book);
            return "BookEditForm";  
        }
    
        //保存书
        @RequestMapping(value = "/book_save")
        public String saveBook(@ModelAttribute Book book) {
            Category category = iBookService.getCategory(book.getCategory().getId());
            book.setCategory(category);
            iBookService.save(book);
            return "redirect:/book_list";
        }
    
        //更新书
        @RequestMapping(value = "/book_update")
        public String updateBook(@ModelAttribute Book book) {
            Category category = iBookService.getCategory(book.getCategory().getId());
            book.setCategory(category);
            iBookService.update(book);
            return "redirect:/book_list";
        }
    
        //列出所有书
        @RequestMapping(value = "/book_list")
        public String listBooks(Model model) {
            List<Book> books = iBookService.getAllBooks();
            model.addAttribute("books",books);
            return "BookList";
        }
    }

#### 4、Service类 ####

##### IBookService接口 #####

package com.linjie.service;
    /**
    * @author 浅然    xulinjie0105@gmail.com
    * @version 创建时间：2018年5月31日 下午2:21:56
    * 接口
    */
    
    import java.util.List;
    
    import com.linjie.pojo.Book;
    import com.linjie.pojo.Category;
    public interface IBookService {
        List<Category> getAllCategories();  //获取所有类别
        Category getCategory(int id);       //获取某个类别
        List<Book> getAllBooks();           //获取所有书
        Book save(Book book);               //保存某本书
        Book update(Book book);             //更新某本书
        Book get(long id);                  //获取某本书
        long getNextId();                   //添加书时获取id(获取到最后一本书的id+1)
    }

##### BookServiceImpl实现类 #####

package com.linjie.service;
    
    import java.util.ArrayList;
    import java.util.List;
    
    import org.springframework.stereotype.Service;
    
    import com.linjie.pojo.Book;
    import com.linjie.pojo.Category;
    
    /**
    * @author 浅然    xulinjie0105@gmail.com
    * @version 创建时间：2018年5月31日 下午2:40:58
    * IBookService接口实现类
    * 初始化数据、获取所有书的类别、获取某个类别、获取所有书、获取某书、保存书、更新书、添加书时获取id(获取到最后一本书的id+1)
    */
    @Service
    public class BookServiceImpl implements IBookService{
    
        private List<Category> categories;      //书类别集合
        private List<Book> books;               //书的集合
    
        //初始化数据
        public BookServiceImpl(){
            //类别初始化
            categories = new ArrayList<Category>();
            Category category1 = new Category(1,"Computing");
            Category category2 = new Category(2,"Travel");
            Category category3 = new Category(3,"Health");
            categories.add(category1);
            categories.add(category2);
            categories.add(category3);
    
            //书本初始化
            books = new ArrayList<Book>();
            books.add(new Book(1L,"9780232231123",
                    "Servlet & JSP:A Tutorial",
                    category1,"Budi Kurniawan"));
            books.add(new Book(2L,"9780232234456",
                    "Effective Java:A Tutorial",
                    category1,"Joshua Bolch"));
        }
    
        //获取所有书的类别
        @Override
        public List<Category> getAllCategories() {
            return categories;
        }
    
        //获取某个类别
        @Override
        public Category getCategory(int id) {
            for(Category category : categories) {
                if(id == category.getId()) {
                    return category;
                }
            }
            return null;
        }
    
        //获取所有书
        @Override
        public List<Book> getAllBooks() {
            return books;
        }
    
        //保存书
        @Override
        public Book save(Book book) {
            book.setId(getNextId());
            books.add(book);
            return book;
        }
    
        //获取某书
        @Override
        public Book get(long id) {
            for(Book book : books) {
                if(id == book.getId()) {
                    return book;
                }
            }
            return null;
        }
    
        //更新书
        @Override
        public Book update(Book book) {
            int bookCount = books.size();
            for(int i = 0; i < bookCount; i++) {
                Book savedBook = books.get(i);
                if(savedBook.getId() == book.getId()) {
                    books.set(i, book);
                    return book;
                }
            }
            return book;
        }   
    
        //添加书时获取id(获取到最后一本书的id+1)
        @Override
        public long getNextId() {
            long id = 0L;
            for(Book book : books) {
                long bookId = book.getId();
                if(bookId > id) {
                    id = bookId;
                }
            }
            return id + 1;
        }
    
    }

#### 5、配置文件 ####

##### web.xml(配置DispatcherServlet) #####

<?xml version="1.0" encoding="UTF-8"?>
    <web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" id="WebApp_ID" version="2.5">
        
        <servlet>
            <servlet-name>springmvc</servlet-name>
            <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
            <load-on-startup>1</load-on-startup>
        </servlet>
    
        
        <servlet-mapping>
            <servlet-name>springmvc</servlet-name>
            <url-pattern>/</url-pattern>
        </servlet-mapping>
    </web-app>

##### springmvc-servlet.xml(1.扫描包、2.配置视图解析器) #####

<?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:p="http://www.springframework.org/schema/p"
        xmlns:mvc="http://www.springframework.org/schema/mvc"
        xmlns:context="http://www.springframework.org/schema/context"
        xsi:schemaLocation="http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.3.xsd
            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-4.3.xsd">
        
        <context:component-scan base-package="com.linjie"></context:component-scan>
        
        <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
            <property name="prefix" value="/WEB-INF/views/"></property>
            <property name="suffix" value=".jsp"></property>
        </bean>
    </beans>

#### 6、视图 ####

注意：使用SpringMVC表单标签需要使用

<%@ taglib prefix="form" uri="http://www.springframework.org/tags/form"%>

##### BookList.jsp页面 #####

<%@ page language="java" contentType="text/html; charset=UTF-8"
        pageEncoding="UTF-8"%>
    <%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
    <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
    <html>
    <head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
    <title>Book List</title>
    </head>
    <body>
        <div>
            <h1>Book List</h1>
            <a href="<c:url value="/book_input"/>">Add Book</a>
            <table>
                <tr>
                    <th>Category</th>
                    <th>Title</th>
                    <th>ISBN</th>
                    <th>Author</th>
                    <th> </th>
                </tr>
                <c:forEach items="${books}" var="book">
                    <tr>
                        <td>${book.category.name}</td>
                        <td>${book.title}</td>
                        <td>${book.isbn}</td>
                        <td>${book.author}</td>
                        <td><a href="book_edit/${book.id}">Edit</a></td>
                    </tr>
                </c:forEach>
            </table>
        </div>
    </body>
    </html>

##### BookAddForm.jsp页面 #####

<%@ page language="java" contentType="text/html; charset=UTF-8"
        pageEncoding="UTF-8"%>
    <%@ taglib prefix="form" uri="http://www.springframework.org/tags/form"%>
    <%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
    <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
    <html>
    <head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
    <title>Add Book Form</title>
    </head>
    <body>
        <div>
            <form:form commandName="book" action="/Springmvc_Demo/book_save" method="post">
                <fieldset>
                    <legend>Add a book</legend>
                    <p>
                        <label for="category">Category:</label>
                        
                        <form:select path="category.id" id="category"
                            items="${categories}" itemLabel="name" itemValue="id">
                        </form:select>
                    </p>
                    <p>
                        <label for="title">Title:</label>
                        <form:input path="title" id="title"/>
                    </p>
                    <p>
                        <label for="author">Author:</label>
                        <form:input path="author" id="author"/>
                    </p>
                    <p>
                        <label for="isbn">ISBN:</label>
                        <form:input path="isbn" id="isbn"/>
                    </p>
                    <p>
                        <input id="reset" type="reset" tabindex="4">
                        <input id="submit" type="submit" tabindex="5" value="Add Book">
                    </p>
                </fieldset>
            </form:form>
        </div>
    </body>
    </html>

##### BookEditForm.jsp页面 #####

<%@ page language="java" contentType="text/html; charset=UTF-8"
        pageEncoding="UTF-8"%>
    <%@ taglib prefix="form" uri="http://www.springframework.org/tags/form"%>
    <%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
    <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
    <html>
    <head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
    <title>Edit Book Form</title>
    </head>
    <body>
        <div>
            <form:form commandName="book" action="/Springmvc_Demo/book_update" mathod="post">
                <fieldset>
                    <legend>Edit a book</legend>
                    <form:hidden path="id"/>
                    <p>
                        <label for="category">Category:</label>
                        <form:select path="category.id" id="category" items="${categories }"
                         itemLabel="name" itemValue="id"></form:select>
                    </p>
                    <p>
                        <label for="title">Title:</label>
                        <form:input path="title" id="title"/>
                    </p>
                    <p>
                        <label for="author">Author:</label>
                        <form:input path="author" id="author"/>
                    </p>
                    <p>
                        <label for="isbn">ISBN:</label>
                        <form:input path="isbn" id="isbn"/>
                    </p>
                    <p>
                        <input id="reset" type="reset" tabindex="4">
                        <input id="submit" type="submit" tabindex="5"
                            value="Upadate Book">
                    </p>
                </fieldset>
            </form:form>
        </div>
    </body>
    </html>

#### 7、jar包的话我将所有jar都导入了以备不时之需 ####

![这里写图片描述][70 1]

### 四、测试应用 ###

地址输入：[http://localhost:8080/Springmvc\_Demo/book\_list][http_localhost_8080_Springmvc_Demo_book_list]

如图为第一次启动应用列出所有书籍

![这里写图片描述][70 2]

点击Add Book，添加书籍  
![这里写图片描述][70 3]

点击Edit修改书籍信息

![这里写图片描述][70 4]

[工程下载][Link 1]

--------------------

#### 参考 ####

《Spring MVC学习指南》

[70]: /images/20220523/b778609adffa4d328a332709e676982d.png
[70 1]: /images/20220523/6df10e4c920845f0a5abbc91ce0e3797.png
[http_localhost_8080_Springmvc_Demo_book_list]: http://localhost:8080/Springmvc_Demo/book_list
[70 2]: /images/20220523/c6990cca9fcf4818a01ac70321d79558.png
[70 3]: /images/20220523/ae8451fb50b14b908ab72177eebe5864.png
[70 4]: /images/20220523/8987732e7b9d441cb1670775394cb564.png
[Link 1]: https://download.csdn.net/download/w_linux/10452279