JAVA语言POI导出EXCEL设置首行标题合并单元格再加上标题居中, 加粗,并且所有单元格加上边框,请给出完整示例

好的，以下是一个完整的示例代码，实现了首行标题合并单元格、标题居中、加粗和单元格边框的要求： ```java import java.io.FileOutputStream; import java.io.IOException; import org.apache.poi.ss.usermodel.BorderStyle; import org.apache.poi.ss.usermodel.CellStyle; import org.apache.poi.ss.usermodel.Font; import org.apache.poi.ss.usermodel.HorizontalAlignment; import org.apache.poi.ss.usermodel.IndexedColors; import org.apache.poi.ss.usermodel.Row; import org.apache.poi.ss.usermodel.Sheet; import org.apache.poi.ss.usermodel.VerticalAlignment; import org.apache.poi.xssf.usermodel.XSSFWorkbook; public class ExcelExportExample { public static void main(String[] args) { // 创建工作簿和活动表 XSSFWorkbook workbook = new XSSFWorkbook(); Sheet sheet = workbook.createSheet("学生成绩单"); // 设置标题 Row titleRow = sheet.createRow(0); titleRow.createCell(0).setCellValue("学生成绩单"); sheet.addMergedRegion(CellRangeAddress.valueOf("A1:C1")); CellStyle titleStyle = workbook.createCellStyle(); titleStyle.setAlignment(HorizontalAlignment.CENTER); Font titleFont = workbook.createFont(); titleFont.setBold(true); titleStyle.setFont(titleFont); titleRow.getCell(0).setCellStyle(titleStyle); // 设置表头 Row headerRow = sheet.createRow(1); headerRow.createCell(0).setCellValue("姓名"); headerRow.createCell(1).setCellValue("语文"); headerRow.createCell(2).setCellValue("数学"); CellStyle headerStyle = workbook.createCellStyle(); headerStyle.setAlignment(HorizontalAlignment.CENTER); headerStyle.setVerticalAlignment(VerticalAlignment.CENTER); headerStyle.setBorderTop(BorderStyle.THIN); headerStyle.setBorderRight(BorderStyle.THIN); headerStyle.setBorderBottom(BorderStyle.THIN); headerStyle.setBorderLeft(BorderStyle.THIN); headerStyle.setFillForegroundColor(IndexedColors.GREY_25_PERCENT.getIndex()); headerStyle.setFillPattern(FillPatternType.SOLID_FOREGROUND); Font headerFont = workbook.createFont(); headerFont.setBold(true); headerStyle.setFont(headerFont); for (int i = 0; i < headerRow.getLastCellNum(); i++) { headerRow.getCell(i).setCellStyle(headerStyle); } // 设置学生成绩 Row dataRow1 = sheet.createRow(2); dataRow1.createCell(0).setCellValue("张三"); dataRow1.createCell(1).setCellValue(90); dataRow1.createCell(2).setCellValue(80); Row dataRow2 = sheet.createRow(3); dataRow2.createCell(0).setCellValue("李四"); dataRow2.createCell(1).setCellValue(85); dataRow2.createCell(2).setCellValue(92); Row dataRow3 = sheet.createRow(4); dataRow3.createCell(0).setCellValue("王五"); dataRow3.createCell(1).setCellValue(88); dataRow3.createCell(2).setCellValue(87); // 设置单元格边框 CellStyle dataStyle = workbook.createCellStyle(); dataStyle.setAlignment(HorizontalAlignment.CENTER); dataStyle.setVerticalAlignment(VerticalAlignment.CENTER); dataStyle.setBorderTop(BorderStyle.THIN); dataStyle.setBorderRight(BorderStyle.THIN); dataStyle.setBorderBottom(BorderStyle.THIN); dataStyle.setBorderLeft(BorderStyle.THIN); for (int i = 2; i <= sheet.getLastRowNum(); i++) { Row row = sheet.getRow(i); for (int j = 0; j < row.getLastCellNum(); j++) { row.getCell(j).setCellStyle(dataStyle); } } // 保存文件 try (FileOutputStream outputStream = new FileOutputStream("example.xlsx")) { workbook.write(outputStream); } catch (IOException e) { e.printStackTrace(); } } } ``` 在上面的代码中，我们首先创建工作簿和活动表，然后使用 `sheet.addMergedRegion()` 将 A1 到 C1 的单元格合并成一个单元格，并使用 `CellStyle` 和 `Font` 分别设置居中和加粗样式。接着，我们设置了表头和学生成绩，并使用循环为表头和学生成绩的单元格设置了边框和填充颜色样式。最后，我们使用 `workbook.write()` 将工作簿保存到本地。