VIP31/novel-demo/src/main/java/com/sf/service/impl/BookChapterServiceImpl.java

package com.sf.service.impl;

import com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper;
import com.sf.dto.resp.BookChapterRespDto;
import com.sf.entity.BookChapter;
import com.sf.mapper.BookChapterMapper;
import com.sf.service.IBookChapterService;
import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import org.springframework.beans.BeanUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.util.ArrayList;
import java.util.List;

/**
 * <p>
 * 小说章节 服务实现类
 * </p>
 *
 * @author baomidou
 * @since 2024-05-25
 */
@Service
public class BookChapterServiceImpl extends ServiceImpl<BookChapterMapper, BookChapter> implements IBookChapterService {

    @Autowired
    private BookChapterMapper bookChapterMapper;

    @Override
    public List<BookChapterRespDto> getBookChapterByBookId(Long bookId) {
        // select * from book_chapter where book_id = '';
        LambdaQueryWrapper<BookChapter> queryWrapper = new LambdaQueryWrapper();
        queryWrapper.eq(BookChapter::getBookId, bookId);
        List<BookChapter> bookChapters = bookChapterMapper.selectList(queryWrapper);
        // 使用普通的方式转换成DTO
        List<BookChapterRespDto> chapterRespDtos = new ArrayList<>();
        bookChapters.forEach(bookChapter -> {
            BookChapterRespDto chapterRespDto = new BookChapterRespDto();
            BeanUtils.copyProperties(bookChapter, chapterRespDto);
            // 补充不同名的属性
            chapterRespDto.setChapterUpdateTime(bookChapter.getUpdateTime());
            chapterRespDtos.add(chapterRespDto);
        });
        // stream流的写法
        List<BookChapterRespDto> chapterRespDtos2 = bookChapters.stream().map(bookChapter -> {
            return BookChapterRespDto.builder()
                    .id(bookChapter.getId())
                    .bookId(bookChapter.getBookId())
                    .chapterName(bookChapter.getChapterName())
                    .chapterNum(bookChapter.getChapterNum())
                    .chapterWordCount(bookChapter.getWordCount())
                    .chapterUpdateTime(bookChapter.getUpdateTime())
                    .isVip(bookChapter.getIsVip().intValue())
                    .build();
        }).toList();
        return chapterRespDtos2;
    }
}