jxls2导入导出工具类，包含list拆分

矫情吗；* 2022-04-13 07:51 412阅读 0赞

最近项目用到 excel导入导出功能，找了很多插件，最后选择了jxls2 。相比jxls1有很大改变  
官方文档：[http://jxls.sourceforge.net/getting\_started.html][http_jxls.sourceforge.net_getting_started.html]  
maven依赖：  
注意其poi版本为4.0

<dependency>
                <groupId>org.apache.poi</groupId>
                <artifactId>poi</artifactId>
                <version>4.0.0</version>
            </dependency>
            <dependency>
                <groupId>org.jxls</groupId>
                <artifactId>jxls</artifactId>
                <version>2.4.7</version>
            </dependency>
            <dependency>
                <groupId>org.jxls</groupId>
                <artifactId>jxls-poi</artifactId>
                <version>1.0.16</version>
            </dependency>
            <dependency>
                <groupId>org.jxls</groupId>
                <artifactId>jxls-jexcel</artifactId>
                <version>1.0.7</version>
            </dependency>
            <dependency>
                <groupId>org.jxls</groupId>
                <artifactId>jxls-reader</artifactId>
                <version>2.0.5</version>
            </dependency>

import org.apache.poi.openxml4j.exceptions.InvalidFormatException;
    import org.jxls.common.Context;
    import org.jxls.reader.ReaderBuilder;
    import org.jxls.reader.XLSReader;
    import org.jxls.util.JxlsHelper;
    import org.slf4j.Logger;
    import org.slf4j.LoggerFactory;
    import org.springframework.core.io.ClassPathResource;
    import org.springframework.web.multipart.MultipartFile;
    import org.xml.sax.SAXException;
    
    import java.io.IOException;
    import java.io.InputStream;
    import java.io.OutputStream;
    import java.util.ArrayList;
    import java.util.List;
    import java.util.Map;
    
    
    public class JxlsUtil {
    
        private static final Logger logger = LoggerFactory.getLogger(JxlsUtil.class);
    
        public static void exportExcel(OutputStream outputStream,
                                       String templateFilePath,
                                       Map<String, Object> model) {
            Context context = new Context();
            if (model != null) {
                for (String key : model.keySet()) {
                    context.putVar(key, model.get(key));
                }
            } else {
                	//你的处理方式 
            }
            try {
                ClassPathResource classPathResource = new ClassPathResource(templateFilePath);
                try (InputStream is = classPathResource.getInputStream()) {
                    JxlsHelper jxlsHelper = JxlsHelper.getInstance();
                    jxlsHelper.setUseFastFormulaProcessor(false);
                    jxlsHelper.processTemplate(is, outputStream, context);
                }
            } catch (Exception e) {
                throw new CustomizeException(e.getMessage());
            }
        }
    
        /**
         * excel读取
         *
         * @param file    文件流
         * @param beans   需处理对象
         * @param xmlPath xml映射文件路径
         * @return 返回传入的bean
         */
        public static void importExcel(MultipartFile file,
                                       Map<String, Object> beans,
                                       String xmlPath) {
            try {
                ClassPathResource classPathResource = new ClassPathResource(xmlPath);
                try (InputStream xmlInputStream = classPathResource.getInputStream()) {
                    XLSReader reader = ReaderBuilder.buildFromXML(xmlInputStream);
                    try (InputStream xlsInputStream = file.getInputStream()) {
                        reader.read(xlsInputStream, beans);
                    }
                }
            } catch (IOException | SAXException | InvalidFormatException e) {
                throw new CustomizeException("处理失败，请检查上传文件格式");
            }
        }
    
        /**
         * list分批
         * @param batchCount 分批数
         * @param list  传入list
         * @param isNewList 是否返回新的list子对象（不使用引用）
         * @param <T> 类型
         * @return 子list集合
         */
        public static  <T> List<List<T>> listUtil(Integer batchCount, List<T> list, Boolean isNewList) {
    
            List<List<T>> lists = new ArrayList<>();
            if (list.size() < batchCount) {
                logger.info("===> 设定分批量大于集合数据量，设定分批量：{},集合数量:{}",batchCount,list.size());
                lists.add(list);
            } else {
                int size = list.size();
                int count = (size + batchCount - 1) / batchCount;
                logger.info("===>指定分批大小：{}, 集合大小：{},分批数：{}",batchCount,list.size(),count);
                for (int i = 0; i < count; i++) {
                    List<T> subList = list.subList(i * batchCount, ((i + 1) * batchCount > size ? size : batchCount * (i + 1)));
                    if (isNewList) {
                        lists.add(new ArrayList<T>(subList));
                    } else {
                        lists.add(subList);
                    }
                }
            }
            return lists;
        }
    
    }

[http_jxls.sourceforge.net_getting_started.html]: http://jxls.sourceforge.net/getting_started.html