自定义导出Excel
需求背景:对象集合,某些字段无需添加到excel表格中,我们只需要给实体类字段添加特定注解实现,尽可能充满灵活性;
具体代码实现:
第一个注解的作用是更好实现Excel表格第一行属性
实体类
具体实现代码
package org.pt.excelutil;
import org.apache.poi.hssf.usermodel.HSSFRow;
import org.apache.poi.hssf.usermodel.HSSFSheet;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.ss.usermodel.Cell;
import org.pt.annotation.ExcludeFromExcel;
import org.pt.annotation.FiledName;
import java.io.FileOutputStream;
import java.io.IOException;
import java.lang.reflect.Field;
import java.util.List;
/*
Excel导出
*/
public class ExcelExport {
public static void writeToExcel(List<?> object,String path) {
HSSFWorkbook workbook = new HSSFWorkbook();
HSSFSheet sheet = workbook.createSheet();
// 第一行写入自定义的属性名
HSSFRow headerRow = sheet.createRow(0);
Field[] fields = object.get(0).getClass().getDeclaredFields();
// 遍历并访问每个字段
for (int i = 0; i < fields.length; i++) {
Field field = fields[i];
field.setAccessible(true);
if (field.isAnnotationPresent(FiledName.class) && !field.isAnnotationPresent(ExcludeFromExcel.class)) {
FiledName annotation = field.getAnnotation(FiledName.class);
Cell cell = headerRow.createCell(i);
cell.setCellValue(annotation.value());
}
}
// 从第二行开始写入属性值
for (int rowNum = 1; rowNum <= object.size(); rowNum++) {
HSSFRow row = sheet.createRow(rowNum);
for (int i = 0; i < fields.length; i++) {
Field field = fields[i];
field.setAccessible(true);
// 判断这个字段是否有注解
if (field.isAnnotationPresent(FiledName.class) && !field.isAnnotationPresent(ExcludeFromExcel.class)) {
Cell cell = row.createCell(i);
Object value = null;
try {
value = field.get(object.get(rowNum - 1));
if (value != null) {
cell.setCellValue(value.toString());
} else {
cell.setCellValue(""); // 或者设置为其他默认值
}
} catch (IllegalAccessException e) {
throw new RuntimeException(e);
}
}
}
}
try (FileOutputStream fileOut = new FileOutputStream(path)) {
workbook.write(fileOut);
System.out.println("Excel file written successfully.");
} catch (IOException e) {
throw new RuntimeException(e);
}
}
}
效果图