1.有了数据绑定，类型总是为了String的HTTP请求参数，可用于填充不同的类型的对象属性

 

2.表单标签库

为了使用这些标签，必须在jsp页面开头处声明这个taglib指令

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

form,input,password,hidden,textarea,checkbox,checkboxs,radiobutton,radiobuttons

select,option,options,errors渲染元素

 

表单标签

1 
     
       2  3  4 commandName它定义了模型属性的名称，其属性用于填充所生成的表单 5  6 @RequestMapping("/book_input") 7 public String inputBook(Model model){ 8  9      model.addAttribute("book",new Book());       10 }11 12 如果没有Model属性，jsp会报错，无法找到commandName属性
     

 

input标签：

1 
     
       2 path:属性，它将这个输入的字段绑定到book的一个属性，绑定到book的isbn属性 5
     

 

数据绑定范例：

 

 

1.Domain

1 package app05a.domain; 2  3 import java.io.Serializable; 4  5 public class Book implements Serializable { 6      7     private static final long serialVersionUID = 1520961851058396786L; 8     private long id; 9     private String isbn;10     private String title;11     private Category category;12     private String author;13     14     public Book() {15     }16     17     public Book(long id, String isbn, String title, 18             Category category, String author) {19         this.id = id;20         this.isbn = isbn;21         this.title = title;22         this.category = category;23         this.author = author;24     }25 26     public long getId() {27         return id;28     }29     public void setId(long id) {30         this.id = id;31     }32     public String getIsbn() {33         return isbn;34     }35     public void setIsbn(String isbn) {36         this.isbn = isbn;37     }38     public String getTitle() {39         return title;40     }41     public void setTitle(String title) {42         this.title = title;43     }44     public Category getCategory() {45         return category;46     }47     public void setCategory(Category category) {48         this.category = category;49     }50     public String getAuthor() {51         return author;52     }53     public void setAuthor(String author) {54         this.author = author;55     }56 }

 

1 package app05a.domain; 2  3 import java.io.Serializable; 4  5 public class Category implements Serializable { 6     private static final long serialVersionUID = 5658716793957904104L; 7     private int id; 8     private String name; 9     10     public Category() {11     }12     13     public Category(int id, String name) {14         this.id = id;15         this.name = name;16     }17     18     public int getId() {19         return id;20     }21     public void setId(int id) {22         this.id = id;23     }24     public String getName() {25         return name;26     }27     public void setName(String name) {28         this.name = name;29     }30 }

 

3.Controller

1 package app05a.controller; 2  3 import java.util.List; 4  5 import org.apache.commons.logging.Log; 6 import org.apache.commons.logging.LogFactory; 7 import org.springframework.beans.factory.annotation.Autowired; 8 import org.springframework.stereotype.Controller; 9 import org.springframework.ui.Model;10 import org.springframework.web.bind.annotation.ModelAttribute;11 import org.springframework.web.bind.annotation.PathVariable;12 import org.springframework.web.bind.annotation.RequestMapping;13 14 import app05a.domain.Book;15 import app05a.domain.Category;16 import app05a.service.BookService;17 18 @Controller19 public class BookController {20 21     @Autowired22     private BookService bookService;23 24     private static final Log logger = LogFactory.getLog(BookController.class);25 26     @RequestMapping(value = "/book_input")27     public String inputBook(Model model) {28         List
     
       categories = bookService.getAllCategories();29         model.addAttribute("categories", categories);30         model.addAttribute("book", new Book());31         return "BookAddForm";32     }33 34     @RequestMapping(value = "/book_edit/{id}")35     public String editBook(Model model, @PathVariable long id) {36         List
      
        categories = bookService.getAllCategories();37         model.addAttribute("categories", categories);38         Book book = bookService.get(id);39         model.addAttribute("book", book);40         return "BookEditForm";41     }42 43     @RequestMapping(value = "/book_save")44     public String saveBook(@ModelAttribute Book book) {45         Category category = bookService.getCategory(book.getCategory().getId());46         book.setCategory(category);47         bookService.save(book);48         return "redirect:/book_list";49     }50 51     @RequestMapping(value = "/book_update")52     public String updateBook(@ModelAttribute Book book) {53         Category category = bookService.getCategory(book.getCategory().getId());54         book.setCategory(category);55         bookService.update(book);56         return "redirect:/book_list";57     }58 59     @RequestMapping(value = "/book_list")60     public String listBooks(Model model) {61         logger.info("book_list");62         List
       
         books = bookService.getAllBooks();63         model.addAttribute("books", books);64         return "BookList";65     }66 }
       
      
     

 

 

4.Service

1 package app05a.service; 2  3 import java.util.List; 4  5 import app05a.domain.Book; 6 import app05a.domain.Category; 7  8 public interface BookService { 9     10     List
     
       getAllCategories();11     Category getCategory(int id);12     List
      
        getAllBooks();13     Book save(Book book);14     Book update(Book book);15     Book get(long id);16     long getNextId();17 18 }
      
     

 

 

5.

1 package app05a.service;  2   3 import java.util.ArrayList;  4 import java.util.List;  5   6 import org.springframework.stereotype.Service;  7   8 import app05a.domain.Book;  9 import app05a.domain.Category; 10  11 @Service 12 public class BookServiceImpl implements BookService { 13      14     /* 15      * this implementation is not thread-safe 16      */ 17     private List
     
       categories; 18     private List
      
        books; 19      20     public BookServiceImpl() { 21         categories = new ArrayList
       
        (); 22         Category category1 = new Category(1, "Computing"); 23         Category category2 = new Category(2, "Travel"); 24         Category category3 = new Category(3, "Health"); 25         categories.add(category1); 26         categories.add(category2); 27         categories.add(category3); 28          29         books = new ArrayList
        
         (); 30         books.add(new Book(1L, "9780980839623",  31                 "Servlet & JSP: A Tutorial",  32                 category1, "Budi Kurniawan")); 33         books.add(new Book(2L, "9780980839630", 34                 "C#: A Beginner's Tutorial", 35                 category1, "Jayden Ky")); 36     } 37  38     @Override 39     public List
         
           getAllCategories() { 40         return categories; 41     } 42      43     @Override 44     public Category getCategory(int id) { 45         for (Category category : categories) { 46             if (id == category.getId()) { 47                 return category; 48             } 49         } 50         return null; 51     } 52  53     @Override 54     public List
          
            getAllBooks() { 55 return books; 56 } 57 58 @Override 59 public Book save(Book book) { 60 book.setId(getNextId()); 61 books.add(book); 62 return book; 63 } 64 65 @Override 66 public Book get(long id) { 67 for (Book book : books) { 68 if (id == book.getId()) { 69 return book; 70 } 71 } 72 return null; 73 } 74 75 @Override 76 public Book update(Book book) { 77 int bookCount = books.size(); 78 for (int i = 0; i < bookCount; i++) { 79 Book savedBook = books.get(i); 80 if (savedBook.getId() == book.getId()) { 81 books.set(i, book); 82 return book; 83 } 84 } 85 return book; 86 } 87 88 @Override 89 public long getNextId() { 90 // needs to be locked 91 long id = 0L; 92 for (Book book : books) { 93 long bookId = book.getId(); 94 if (bookId > id) { 95 id = bookId; 96 } 97 } 98 return id + 1; 99 }100 }
          
         
        
       
      
     

 

5.配置文件

1 
      2 
     
      14         15     
      16     
      17      18     
      19     
      20     
      21     22     
      
       23         
       24         
       25     
      26     27 
     

 

6.视图

1 <%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %> 2  3  4  5  6  7  8  9 10 
     
      11 
      
Book List
12 
      ">Add Book13 
      
       22     
      
      
       14 
         15     
16     
17     
18     
19     
20 
21 
         23         
24         
25         
26         
27         
28     
29 30 
       
        
         
Category
         
Title
         
ISBN
         
Author
         
 
        
        
         
${book.category.name}
         
${book.title}
         
${book.isbn}
         
${book.author}
         
Edit
        
       
      
31 
     
32 33 

 

1 <%@ taglib prefix="form" uri="http://www.springframework.org/tags/form" %> 2 <%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %> 3  4  5  6  7  8  9 10 11 
     
      12 
      
       13     
       
        14         
        
Add a book
15         
        
16             Category: 17              
         20         
21         
        
22             Title: 23             
         24         
25         
        
26             Author: 27             
         28         
29         
        
30             ISBN: 31             
         32         
33         34         
        
35             36             38         
39     
       
40 
      41 
     
42 43 

 

 

1 <%@ taglib prefix="form" uri="http://www.springframework.org/tags/form" %> 2 <%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %> 3  4  5  6  7  8  9 10 11 
     
      12 
      
       13     
       
        14         
        
Edit a book
15         
        16         
        
17             Category: 18              
         20         
21         
        
22             Title: 23             
         24         
25         
        
26             Author: 27             
         28         
29         
        
30             ISBN: 31             
         32         
33         34         
        
35             36             38         
39     
       
40 
      41 
     
42 43 

 

7.测试应用

http://localhost:8080/app05a/book_list