通过自定义注解+反射的形式，使用POI实现excel的导入导出

自定义注解：

package com.example.demo.annotation;import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;/*** Created by linjiaming*/
@Target(ElementType.FIELD)
@Retention(RetentionPolicy.RUNTIME)
public @interface ExcelAnnotation {String headName();int order();String datePattern() default "yyyyMMdd HH:mm:ss";enum DataType {String,Number,Date,}/*** 数据类型，可以是String，Number(数字型)，Date等类型* @return*/DataType type() default DataType.String;}

实体类：

package com.example.demo.entity;import com.example.demo.annotation.ExcelAnnotation;
import com.example.demo.annotation.ExcelAnnotation.DataType;
import java.util.Date;
import lombok.Data;@Data
public class Student {private Long id;@ExcelAnnotation(headName = "学号", order =0)private String stuNo;@ExcelAnnotation(headName = "姓名", order =1)private String name;@ExcelAnnotation(headName = "学院", order =3)private String academy;@ExcelAnnotation(headName = "专业",order = 4)private String major;@ExcelAnnotation(headName = "年级", order = 5)private String grade;@ExcelAnnotation(headName = "班级", order = 6)private String classes;@ExcelAnnotation(headName = "年龄", order = 2)private String age;@ExcelAnnotation(headName = "入学日期", order = 7, datePattern ="yyyy/MM/dd HH:mm:ss",type = DataType.Date)private Date entryDate;}

excel导入导出工具类：

/*** Created by linjiaming*/
public class ExcelUtils {private static ExcelUtils instance;private ExcelUtils(){}/*** 单例模式* @return*/public static ExcelUtils getInstance() {if (instance == null) {instance = new ExcelUtils();}return instance;}/*** excel的导出* @param out* @param infos*/public void exportExcel (OutputStream out, List<?> infos) {try {XSSFWorkbook xssfWorkbook = new XSSFWorkbook();XSSFSheet sheet = xssfWorkbook.createSheet();sheet.createRow(0);Map<Field,Integer> map = new LinkedHashMap<>();for (Object o : infos ) {Field[] fields = o.getClass().getDeclaredFields();for (Field field : fields) {if (field.isAnnotationPresent(ExcelAnnotation.class)) {ExcelAnnotation annotation = field.getAnnotation(ExcelAnnotation.class);map.put(field, annotation.order());}}}List<Entry<Field,Integer>> list = new ArrayList<Entry<Field,Integer>>(map.entrySet());Collections.sort(list, (o1, o2) -> o1.getValue().compareTo(o2.getValue()));List<Field> excelFields = new ArrayList<>();for(Entry<Field,Integer> map1 : list){excelFields.add(map1.getKey());}List<ExcelAnnotation> annotations = new ArrayList<>();for (Field excelField : excelFields) {annotations.add(excelField.getAnnotation(ExcelAnnotation.class));}addDataToExcel(xssfWorkbook, infos, excelFields, annotations, sheet);xssfWorkbook.write(out);} catch (Exception e) {e.printStackTrace();}}private <T> void addDataToExcel(XSSFWorkbook wb, List<T> dataset,List<Field> excelFields, List<ExcelAnnotation> attributes,Sheet sheet)throws IllegalAccessException, NoSuchMethodException, InvocationTargetException, ParseException {XSSFCellStyle style = wb.createCellStyle();// 居中style.setAlignment(HorizontalAlignment.CENTER);style.setVerticalAlignment(VerticalAlignment.CENTER);// excel放入第一行列的名称Row row = sheet.createRow(0);for (int j = 0; j < excelFields.size(); j++) {Cell cell = row.createCell(j);ExcelAnnotation oneAttribute = attributes.get(j);cell.setCellValue(oneAttribute.headName());cell.setCellStyle(style);}// 添加数据到excelfor(int i=0;i<dataset.size();i++) {// 数据行号从1开始,因为第0行放的是列的名称row = sheet.createRow(i+1);for(int j=0;j<attributes.size();j++) {Cell cell = row.createCell(j);ExcelAnnotation annotation = attributes.get(j);style = wb.createCellStyle();// 居中style.setAlignment(HorizontalAlignment.CENTER);style.setVerticalAlignment(VerticalAlignment.CENTER);// 四个边框style.setBorderBottom(BorderStyle.THIN);style.setBorderLeft(BorderStyle.THIN);style.setBorderRight(BorderStyle.THIN);style.setBorderTop(BorderStyle.THIN);cell.setCellStyle(style);// 根据属性名获取属性值String cellValue = BeanUtils.getProperty( dataset.get(i), excelFields.get(j).getName());if (DataType.Date.equals(annotation.type())){String date = DateTimeUtil.getFormatDateFromGLWZString(cellValue, annotation.datePattern());cell.setCellValue(date);}else {cell.setCellValue(cellValue);}}}}/*** excel的导入* @param inputStream* @param clazz* @return* @throws IOException* @throws InstantiationException* @throws IllegalAccessException* @throws InvocationTargetException* @throws NoSuchMethodException*/public  List<?> importExcel(InputStream inputStream, Class<?> clazz)throws IOException, InstantiationException, IllegalAccessException, InvocationTargetException, NoSuchMethodException {Workbook workbook = WorkbookFactory.create(inputStream);Sheet sheet = workbook.getSheetAt(0);Row titleCell = sheet.getRow(0);List<Object> dataList = new ArrayList<>(sheet.getLastRowNum());Object datum;Map<String, Field> fieldMap = getFieldMap(clazz);for (int i = 1; i <= sheet.getLastRowNum(); i++) {Row row = sheet.getRow(i);datum = clazz.newInstance();int minCell = row.getFirstCellNum();int maxCell = row.getLastCellNum();for (int cellNum = minCell; cellNum <= maxCell; cellNum++) {Cell title = titleCell.getCell(cellNum);if (title == null) {continue;}String tag = title.getStringCellValue();Field field = fieldMap.get(tag);if (field == null) {continue;}Class<?> type = field.getType();Object value = null;Cell cell = row.getCell(cellNum);if (cell == null) {continue;}if (type.equals(Date.class)){value = cell.getDateCellValue();} else {value = cell.getStringCellValue();}PropertyUtils.setProperty(datum, field.getName(), value);}dataList.add(datum);}return dataList;}/*** key :headName  val:该名称对应的字段* @param clazz* @param <T>* @return*/private static <T> Map<String, Field> getFieldMap(Class<T> clazz) {Field[] fields = clazz.getDeclaredFields();Map<String, Field> fieldMap = new HashMap<>();for (Field field : fields) {if (field.isAnnotationPresent(ExcelAnnotation.class)) {ExcelAnnotation annotation = field.getAnnotation(ExcelAnnotation.class);fieldMap.put(annotation.headName(), field);}}return fieldMap;}

@Slf4j
public class DateTimeUtil {private static SimpleDateFormat simpleDateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");/*** 获得所需要的日期格式** @param date* @param format yyyy-MM-dd HH:mm:ss* @return*/public static Date getFormatDateFromString(String date, String format) {SimpleDateFormat formatter = new SimpleDateFormat(format);Date formatDate = null;try {formatDate = formatter.parse(date);} catch (ParseException e) {e.printStackTrace();}return formatDate;}public static String getFormatDateFromGLWZString(String strdate, String format)throws ParseException {DateFormat df = new SimpleDateFormat("EEE MMM dd HH:mm:ss zzz yyyy", Locale.US);Date date =df.parse(strdate);//     System.out.println(date.toString());SimpleDateFormat sdf=new SimpleDateFormat(format);return sdf.format(date);}
}

简单测试：

public static void main(String[] args)throws IOException, InvocationTargetException, NoSuchMethodException, InstantiationException, IllegalAccessException {ExcelUtils excelUtils = getInstance();String filepath = "D:\\学生信息表.xlsx";File file = new File(filepath);List<?> objects =  excelUtils.importExcel(new FileInputStream(file), Student.class);System.out.println(objects);}

通过自定义注解+反射的形式，使用POI实现excel的导入导出相关推荐

蓄力-利用POI进行excel的导入导出（包含图片）
这里写自定义目录标题利用POI进行excel的导入导出引入的jar包 excel导入主方法: 将excel里面的图片转成数据 xls格式 xlsx格式将图片数据转成字节流的方式传输到FTP服务 ...
手摸手教学-利用原生POI对excel的导入导出以及阿里的easyexcel的基本操作
文章目录原生POI对excel的导入导出以及阿里的easyexcel的基本操作首先是最原始的POI操作excel 其次是POI操作excel对数据库的导入导出最后是阿里的easyexcel的简单 ...
Poi的Excel的导入导出支持2007
需要导入 poi-3.7.jar commons-io-2.4.jar Excel2003导出 import java.io.File; import java.io.FileOutputStream ...
通过POI操作Excel的导入导出
项目地址https://github.com/zhuhaitao666/excel.git 这里罗列部分核心代码 1.引入依赖和配置 <dependency><groupId> ...
java自定义注解实现excel数据导入导出,设置单元格数据验证与生成省市区多列联动效果
本文通过自定义注解实现excel数据导入导出.以及设置excel文件中列数据验证,即用户在excel文件中输入数据时就可以对数据格式验证是否符合,节省了程序中过多的数据验证操作,注解还额外提供了一系列 ...
POI之excel固定模板导出
POI之excel固定模板导出一.简介二.excel模板三.项目中maven依赖四.Excel模板操作代码五.Controller层excel模板导出接口代码六.导出excel 一.简介 ...
POI读取Excel模板并导出大量数据
POI读取Excel模板并导出大量数据我在使用XSSFWorkbook读取Excel模板并导出大量数据(百万级)时,发现很长时间没有响应,debugger模式发现在读取第三四十万条数据时,程序直接停 ...
【开发随机】JAVA+POI+自定义注解+反射构建自定义工具类实现快捷简便的Excel模板化导出(附demo代码)
220907更新项目UAT期间,用户反映了一个问题,数据量稍大的情况下,会出现"从某一行开始,往下所有行设置的字体和字体大小不生效"的BUG. 经过排查,发现原因是:POI的XS ...
玩转POI、EasyExcel报表导入导出！
POI.EasyExcel报表导出前言一.POI操作Excel 1.1 导入依赖包 1.2 编写测试代码: 1.3 03和07版本的区别二.大文件写入 2.1 大文件写HSSF 2.2 大文件写 ...
java使用POI实现Excel批量导入数据。
1.背景项目中有使用easypoi,处理常规excel问题,但是现在有个需求,需要动态生成导出的报表字段.同时,根据导入的excel,增加数据信息.(有可能会出现,导入的报表是几天前下载的,不会最新 ...

通过自定义注解+反射的形式，使用POI实现excel的导入导出

自定义注解：

实体类：

excel导入导出工具类：

简单测试：

通过自定义注解+反射的形式，使用POI实现excel的导入导出相关推荐

最新文章

热门文章