原创作品，可以转载，但是请标注出处地址：https://www.cnblogs.com/V1haoge/p/9971043.html
SpringBoot整合MyBatis分页插件PageHelper
步骤
第一步：首先整合MyBatis
参照之前SpringBoot整合系列-整合MyBatis
第二步：添加必要的依赖
<dependency><groupId>com.github.pagehelper</groupId><artifactId>pagehelper</artifactId><version>4.1.6</version>
</dependency>第三步：添加必要的配置
无
第四步：添加必要的配置类
@Configuration
public class PageHelperConfig {@Beanpublic PageHelper pageHelper(){PageHelper pageHelper = new PageHelper();Properties properties = new Properties();properties.setProperty("offsetAsPageNum","true");properties.setProperty("rowBoundsWithCount","true");properties.setProperty("reasonable","true");properties.setProperty("dialect","mysql"); //配置mysql数据库的方言pageHelper.setProperties(properties);return pageHelper;}
}第五步：使用插件
6-1 定义mapper，延用之前的mapper
BookRepository.xml
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.example.springbootdemo.mapper.BookRepository"><!--省略多余内容--><select id="getBooks" resultMap="bookResultMap">select * from BOOK WHERE 1=1<if test="bookId != null">and BOOK_ID = #{bookId}</if><if test="pageNum != null">and PAGE_NUM = #{pageNum}</if><if test="bookType != null">and BOOK_TYPE = #{bookType}</if><if test="bookDesc != null">and BOOK_DESC = #{bookDesc}</if><if test="bookPrice != null">and BOOK_PRICE = #{bookPrice}</if><if test="bookName != null">and BOOK_NAME = #{bookName}</if></select><select id="count" resultType="int">select count(1) from BOOK WHERE 1=1<if test="bookId != null">and BOOK_ID = #{bookId}</if><if test="pageNum != null">and PAGE_NUM = #{pageNum}</if><if test="bookType != null">and BOOK_TYPE = #{bookType}</if><if test="bookDesc != null">and BOOK_DESC = #{bookDesc}</if><if test="bookPrice != null">and BOOK_PRICE = #{bookPrice}</if><if test="bookName != null">and BOOK_NAME = #{bookName}</if></select><resultMap id="bookResultMap" type="Book"><id column="BOOK_ID" property="bookId"/><result column="PAGE_NUM" property="pageNum"/><result column="BOOK_NAME" property="bookName"/><result column="BOOK_TYPE" property="bookType"/><result column="BOOK_DESC" property="bookDesc"/><result column="BOOK_PRICE" property="bookPrice"/><result column="CREATE_TIME" property="createTime"/><result column="MODIFY_TIME" property="modifyTime"/></resultMap>
</mapper>BookRepository.java
public interface BookRepository {//省略多余内容List<Book> getBooks(Book book);int count(Book book);
}6-2 定义service
@Service
@Log4j2
public class BookService {@Autowiredprivate BookRepository bookRepository;// 省略多余内容public ResponseEntity<PageInfo<Book>> getBooksByPageHelper(int pageId, int pageSize) {PageHelper.startPage(pageId, pageSize);List<Book> books = bookRepository.getBooks(Book.builder().build());int totalNum = bookRepository.count(Book.builder().build());PageInfo<Book> page = new PageInfo<>();page.setPageNum(pageId);page.setPageSize(pageSize);page.setSize(totalNum);page.setList(books);return ResponseEntity.ok(page);}
}此处使用PageHelper提供的PageInfo来承载分页信息，你也可以自定义分页模型来进行承载，但一般情况下使用给定的完全能满足要求
6-3 定义controller
@RestController
@RequestMapping("/book")
@Api(description = "书籍接口")
@Log4j2
public class BookApi {@Autowiredprivate BookService bookService;// 省略多余内容@RequestMapping(value = "/getBooksByPageHelper", method = RequestMethod.GET)@ApiOperation(value = "分页获取书籍", notes = "通过PageHelper分页获取书籍", httpMethod = "GET")public ResponseEntity<PageInfo<Book>> getBooksByPageHelper(final int pageId, final int pageNum){return bookService.getBooksByPageHelper(pageId, pageNum);}}
