SSM整合框架之多对多查询

什么是SSM框架：
SSM框架就是Spring、SpringMVC、MyBatis三个框架的整合，是标准的MVC模式，将整个系统划分为表现层、Controller层、Service层、Dao层三层。使用SpringMVC负责请求的转发和视图管理，Spring实现业务对象管理，Mybatis作为数据对象的持久化引擎

简单介绍了下SSM，就直接上代码吧！

先引入jar包

pom.xml

     
          
        4.0.2.RELEASE  
          
        3.2.6  
          
        1.7.7  
        1.2.17  
     
    
    
        
            junit
            junit
            3.8.1
               
            test
        
        
        
           
          
            org.springframework  
            spring-core  
            ${spring.version}  
          
  
          
            org.springframework  
            spring-web  
            ${spring.version}  
          
          
            org.springframework  
            spring-oxm  
            ${spring.version}  
          
          
            org.springframework  
            spring-tx  
            ${spring.version}  
          
  
          
            org.springframework  
            spring-jdbc  
            ${spring.version}  
          
  
          
            org.springframework  
            spring-webmvc  
            ${spring.version}  
          
          
            org.springframework  
            spring-aop  
            ${spring.version}  
          
  
          
            org.springframework  
            spring-context-support  
            ${spring.version}  
          
  
          
            org.springframework  
            spring-test  
            ${spring.version}  
          
          
          
            org.mybatis  
            mybatis  
            ${mybatis.version}  
          
           
          
            org.mybatis  
            mybatis-spring  
            1.2.2  
          
        
           
          
            javax  
            javaee-api  
            7.0  
          
        
           
          
            mysql  
            mysql-connector-java  
            5.1.36  
          
          
          
            commons-dbcp  
            commons-dbcp  
            1.2.2  
          
        
          
          
            jstl  
            jstl  
            1.2  
          
          
          
          
            log4j  
            log4j  
            ${log4j.version}  
          
          
          
          
            com.alibaba  
            fastjson  
            1.1.41  
          
  
          
            org.slf4j  
            slf4j-api  
            ${slf4j.version}  
          
  
          
            org.slf4j  
            slf4j-log4j12  
            ${slf4j.version}  
          
          
          
          
            org.codehaus.jackson  
            jackson-mapper-asl  
            1.9.13  
          
          
          
            commons-fileupload  
            commons-fileupload  
            1.3.1  
          
          
            commons-io  
            commons-io  
            2.4  
          
          
            commons-codec  
            commons-codec  
            1.9  
          
    
    
    
        maven01
        
            
                org.eclipse.jetty
                jetty-maven-plugin
                9.2.8.v20150217
                
                    
                        80
                    
                    shutdown
                    9966
                
            
        
    

写配置文件

web.xml

  ssm_bookstore
  
    index.html
    index.htm
    index.jsp
    default.html
    default.htm
    default.jsp
  
  
    bookstore

org.springframework.web.servlet.DispatcherServlet

  contextConfigLocation
  classpath*:spring_MVC.xml

1
 
  
    bookstore
    /
  


    contextConfigLocation
    classpath*:application_Context.xml
  

  
    org.springframework.web.context.ContextLoaderListener
  

spring_MVC.xml

application_context.xml

spring_mybatis.xml

创建表

t_book

t_author

t_book_author 创建多对多的关系需要中间表

pojo实体类

书的实体类

package com.bs.admin.pojo;

    import java.io.Serializable;
    import java.util.HashSet;
    import java.util.Set;

/**
 * 
* 
Title: Book
  
* 
Description: Book实体类
  
* @author Jack.Hu
* 
 @date 2018年11月21日
 */
public class Book implements Serializable {

private static final long serialVersionUID = 597733879789573558L;
private Long primaryId;
private Long bookId;
private String bookName;
private Set authors = new HashSet(); // 作者与书，多对多
private String bookCategory;  // 书的种类
private Long bookPurchasePrice;  // 进价
private Long bookSalesPrice;  // 售价
private String bookProfile;  // 简介
private String bookCoverImage;  // 图片路径
private Long publisherId;  // 出版社id
private Long printId;  // 印刷id
private Set activity = new HashSet();  // 活动与书多对多

public Book(){
	
}
public Book(Long primaryId, Long bookId, String bookName, Set authors, String bookCategory, Long bookPurchasePrice,Long bookSalesPrice, String bookProfile, String bookCoverImage, Long publisherId, Long printId, Set activity) {
	this.primaryId = primaryId;
	this.bookId = bookId;
	this.bookName = bookName;
	this.authors = authors;
	this.bookCategory = bookCategory;
	this.bookPurchasePrice = bookPurchasePrice;
	this.bookSalesPrice = bookSalesPrice;
	this.bookProfile = bookProfile;
	this.bookCoverImage = bookCoverImage;
	this.publisherId = publisherId;
	this.printId = printId;
	this.activity = activity;
}
@Override
public String toString() {
	return "Book [主键：" + primaryId + ", 书号：" + bookId + ", 书名：" + bookName +", 作者："+ authors + ", 种类：" + bookCategory + ", 进价：" + bookPurchasePrice + ", 售价：" + bookSalesPrice
			+ ", 简介：" + bookProfile + ", 图片路径：" + bookCoverImage + ", 出版者id：" + publisherId + ", 印刷商id：" + printId +", 活动：" + activity + "]";
}
// .......忽略get set方法.......
}

作者的实体类

package com.bs.admin.pojo;

import java.io.Serializable;
import java.util.HashSet;
import java.util.Set;

/**
 * 
* 
Title: Author
  
* 
Description: 作者的实体类
  
* @author  jack.Hu
* 
 @date 2018年11月21日
 */
public class Author implements Serializable {

private static final long serialVersionUID = -2631951426846305889L;
private Integer authorId;
private String authorName;
private Set books = new HashSet();

public Author(){
	
}
public Author(Integer authorId, String authorName, Set books) {
	this.authorId = authorId;
	this.authorName = authorName;
	this.books = books;
}
@Override
public String toString() {
	return "Author [authorId=" + authorId + ", authorName=" + authorName + ", book：" + books +"]";
}
// .......忽略get set方法.......
}

Mapper层

BookMapper.xml

  
  		select ,
		from t_book b,t_author a,t_book_author ba 
		where ba.book_id = b.book_id 
		and ba.author_id = a.author_id 
		and b.book_id = #{bookId}
  


		
		
		



		primary_id, b.book_id,b.book_name,b.book_category,b.book_purchasePrice,b.book_salesPrice,
		b.book_profile,b.book_coverImage,b.publisher_id,b.print_id     



		a.author_id, a.author_name

BookMapper接口

package com.bs.admin.mapper;

import com.bs.admin.pojo.Book;

public interface BookMapper {

	Book getBookByBookId(Long bookId);
	
	Integer createBook(Book book); 
}

dao层

接口

package com.bs.admin.dao;

import org.springframework.stereotype.Repository;

import com.bs.admin.pojo.Book;

@Repository
public interface BookDao {

	Book retrieveBookByBookId(Long bookId); 
	
}

实现类

package com.bs.admin.dao.impl;

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

import com.bs.admin.dao.BookDao;
import com.bs.admin.mapper.BookMapper;
import com.bs.admin.pojo.Book;

@Repository
public class BookDaoImpl implements BookDao {

	@Autowired
	private BookMapper bm;
	
	@Override
	public Book retrieveBookByBookId(Long bookId) {
		Book book = bm.getBookByBookId(bookId);
		return book;
	}

}

service层

接口

package com.bs.admin.service;

import org.springframework.stereotype.Service;

import com.bs.admin.pojo.Book;

@Service
public interface  BookService {

	Book getBookByBookId(Long bookId);
}

实现类

package com.bs.admin.service.impl;

import java.util.Set;

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

import com.bs.admin.dao.BookDao;
import com.bs.admin.dao.impl.BookDaoImpl;
import com.bs.admin.pojo.Book;
import com.bs.admin.service.BookService;

@Service
public class BookServiceImpl implements BookService{

	@Autowired
	private BookDao bd; 
	
	@Override
	public Book getBookByBookId(Long bookId) {
		Book book = bd.retrieveBookByBookId(bookId);
		return book;
	}
}

controller层

BookstoreController

package com.bs.admin.controller;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.bind.annotation.RestController;

import com.bs.admin.pojo.Author;
import com.bs.admin.pojo.Book;
import com.bs.admin.service.AuthorService;
import com.bs.admin.service.BookService;

@RestController
@RequestMapping("bookstore")
public class BookstoreController {

	@Autowired
	private BookService bs;
	
	@Autowired
	private AuthorService as;
	
	@GetMapping("{bookId}/getBook")
	public @ResponseBody Book getBook(@PathVariable("bookId") Long bookId) {
		Book book = bs.getBookByBookId(bookId);
		System.out.println("book对象:   " + book);
		return book;
	}
}

浏览器

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