org.apache.poi      poi      5.2.2                  org.apache.poi      poi-ooxml      5.2.2    

部分需要注意的问题，通过注释的方式写在代码里面了，看代码的时候需要注意下注释

1、excel Cell单元格背景色+颜色名称对照关系

        public static void setBackgroundColorCellStyle() throws ioException {        HSSFWorkbook workbook = new HSSFWorkbook();        HSSFSheet sheet = workbook.createSheet("excel样式设置");        int rowIndex = 0;        for (IndexedColors color : IndexedColors.values()) {            short colorIndex = color.getIndex();            HSSFCellStyle cell1Style = workbook.createCellStyle();            // 设置的背景颜色            cell1Style.setFillForegroundColor(colorIndex);            // 填充效果（全景填充）            cell1Style.setFillPattern(FillPatternType.SOLID_FOREGROUND);            cell1Style.setAlignment(HorizontalAlignment.CENTER);            cell1Style.setVerticalAlignment(VerticalAlignment.CENTER);            HSSFRow row = sheet.createRow(rowIndex++);            row.setHeight((short) (25 * 20));            // 第一列            HSSFCell cell1 = row.createCell(0);            cell1.setCellStyle(cell1Style);            cell1.setCellValue("X:" + colorIndex);            // 第二列            HSSFCellStyle cell2Style = workbook.createCellStyle();            cell2Style.setAlignment(HorizontalAlignment.CENTER);            cell2Style.setVerticalAlignment(VerticalAlignment.CENTER);            HSSFCell cell2 = row.createCell(1);            cell2.setCellStyle(cell2Style);            cell2.setCellValue(color.name());            // 设置列宽            sheet.setColumnWidth(0, 10 * 256 + 185);            sheet.setColumnWidth(1, 35 * 256 + 185);        }        FileOutputStream outputStream = new FileOutputStream("D:/temp/Excel背景颜色列表.xlsx");        workbook.write(outputStream);        outputStream.close();        workbook.close();    }

2、Excel Cell单元格背景填充样式+颜色填充对照关系

        public static void setFillBackgroundColor() throws IOException {        HSSFWorkbook workbook = new HSSFWorkbook();        HSSFSheet sheet = workbook.createSheet("excel填充设置");        int rowIndex = 0;        short colorIndex = IndexedColors.RED.getIndex(); // 选择红色（可参照上图背景色色号） --> 10        // 填充样式        for (FillPatternType patternType : FillPatternType.values()) {            HSSFCellStyle cell1Style = workbook.createCellStyle();            // 设置的背景颜色            cell1Style.setFillForegroundColor(colorIndex);            // 填充效果（全景填充）            cell1Style.setFillPattern(patternType);            // 设置垂直居中            cell1Style.setAlignment(HorizontalAlignment.CENTER);            cell1Style.setVerticalAlignment(VerticalAlignment.CENTER);            // 设置字体            HSSFFont font = workbook.createFont();            // 加粗            font.setBold(true);            cell1Style.setFont(font);            HSSFRow row = sheet.createRow(rowIndex++);            // 设置行高：height = 磅 * 20 （1磅=0.353毫米=20缇）-> POI中行高是"缇(twips)"            row.setHeight((short) (25 * 20));            // 第一列            HSSFCell cell1 = row.createCell(0);            cell1.setCellStyle(cell1Style);            cell1.setCellValue("code:" + patternType.getCode());            HSSFCellStyle cell2Style = workbook.createCellStyle();            // 设置垂直居中            cell2Style.setAlignment(HorizontalAlignment.CENTER);            cell2Style.setVerticalAlignment(VerticalAlignment.CENTER);            // 第二列            HSSFCell cell2 = row.createCell(1);            cell2.setCellStyle(cell2Style);            cell2.setCellValue(patternType.name());            // 设置列宽: width = 256*磅 + 185            sheet.setColumnWidth(0, 10 * 256 + 185);            sheet.setColumnWidth(1, 24 * 256 + 185);        }        FileOutputStream outputStream = new FileOutputStream("D:/temp/Excel背景填充效果.xlsx");        workbook.write(outputStream);        outputStream.close();        workbook.close();    }

3、Excel Cell字体样式设置+对照图

        public static void setCellFontStyle() throws IOException {        HSSFWorkbook workbook = new HSSFWorkbook();        HSSFSheet sheet = workbook.createSheet("excel字体样式");        HSSFCellStyle cellStyle = workbook.createCellStyle();        HSSFFont font = workbook.createFont();        // 字体加粗        font.setBold(true);        // 字体倾斜        font.setItalic(true);        // 字体删除线        font.setStrikeout(true);        // 字体颜色        font.setColor(IndexedColors.YELLOW.getIndex());        // 字体大小:字号        font.setFontHeightInPoints((short) 14);        // 设置行高        // font.setFontHeight((short) 14);        // 字体        font.setFontName("宋体");        cellStyle.setFont(font);        // 设置文字垂直居中        cellStyle.setAlignment(HorizontalAlignment.CENTER);        cellStyle.setVerticalAlignment(VerticalAlignment.CENTER);        // 设置单元格内容自动换行（文字超出列宽自动换行）        cellStyle.setWrapText(true);        HSSFRow row = sheet.createRow(0);        HSSFCell cell = row.createCell(0);        cell.setCellStyle(cellStyle);        cell.setCellValue("字体");        row.setHeight((short) (30 * 20));        sheet.setColumnWidth(0, 30 * 256 + 185);        FileOutputStream outputStream = new FileOutputStream("D:/temp/Excel字体样式.xlsx");        workbook.write(outputStream);        outputStream.close();        workbook.close();    }

4、Excel 行高、列宽设置

        public static void setRowHeightAndCellWidth() throws IOException {        HSSFWorkbook workbook = new HSSFWorkbook();        HSSFSheet sheet = workbook.createSheet("excel行高、列宽");        // 定义一个5行、5列的数据        int[][] data = {{1, 2, 3, 4, 5}, {6, 7, 8, 9, 10}, {11, 12, 13, 14, 15}, {16, 17, 18, 19, 20}, {21, 22, 23, 24, 25}};        for (int rowIndex = 0; rowIndex < data.length; rowIndex++) {            int[] cellData = data[rowIndex];            HSSFRow row = sheet.createRow(rowIndex);            // 行高计算方式：缇(twips) = 磅 * 20 ==> 换算 1磅=20缇            row.setHeight((short) (25 * 20));            for (int cellIndex = 0; cellIndex < cellData.length; cellIndex++) {                HSSFCell cell = row.createCell(cellIndex);                // 列宽计算方式：8磅 * 256 + 185                sheet.setColumnWidth(cellIndex, 8 * 256 + 185);                cell.setCellValue(cellData[cellIndex]);            }        }        FileOutputStream outputStream = new FileOutputStream("D:/temp/Excel行高、列宽.xlsx");        workbook.write(outputStream);        outputStream.close();        workbook.close();    }

5、Excel单元格边框设置+边框类型图片对比

        public static void setAllBorderStyle() throws IOException {        HSSFWorkbook workbook = new HSSFWorkbook();        HSSFSheet sheet = workbook.createSheet("excel单元格边框样式");        // ======================= 设置边框        int rowIndex = 0;        for (BorderStyle borderStyle : BorderStyle.values()) {            int cellIndex = 0;            HSSFRow row = sheet.createRow(rowIndex++);            row.setHeight((short) (35 * 20));            // 第一列            HSSFCell cell = row.createCell(cellIndex);            HSSFCellStyle topBorderStyle = workbook.createCellStyle();            // 上边框样式            topBorderStyle.setBorderTop(borderStyle);            cell.setCellValue("设置上边框(" + borderStyle.name() + ")");            cell.setCellStyle(topBorderStyle);            sheet.setColumnWidth(cellIndex, 35 * 256 + 185);            cellIndex += 2;            // 第三列            HSSFCell cell2 = row.createCell(cellIndex);            HSSFCellStyle bottomBorderStyle = workbook.createCellStyle();            // 下边框样式            bottomBorderStyle.setBorderBottom(borderStyle);            cell2.setCellValue("设置下边框(" + borderStyle.name() + ")");            cell2.setCellStyle(bottomBorderStyle);            sheet.setColumnWidth(cellIndex, 35 * 256 + 185);            cellIndex += 2;            // 第五列            HSSFCell cell3 = row.createCell(cellIndex);            HSSFCellStyle leftBorderStyle = workbook.createCellStyle();            // 左边框样式            leftBorderStyle.setBorderLeft(borderStyle);            cell3.setCellValue("设置左边框(" + borderStyle.name() + ")");            cell3.setCellStyle(leftBorderStyle);            sheet.setColumnWidth(cellIndex, 35 * 256 + 185);            cellIndex += 2;            // 第七列            HSSFCell cell4 = row.createCell(cellIndex);            HSSFCellStyle rightBorderStyle = workbook.createCellStyle();            // 左边框样式            rightBorderStyle.setBorderRight(borderStyle);            cell4.setCellValue("设置右边框(" + borderStyle.name() + ")");            cell4.setCellStyle(rightBorderStyle);            sheet.setColumnWidth(cellIndex, 35 * 256 + 185);        }        // ================= 设置边框并设置颜色        rowIndex += 2;        for (BorderStyle borderStyle : BorderStyle.values()) {            int cellIndex = 0;            HSSFRow row = sheet.createRow(rowIndex++);            row.setHeight((short) (35 * 20));            // 第一列            HSSFCell cell = row.createCell(cellIndex);            HSSFCellStyle topBorderStyle = workbook.createCellStyle();            // 上边框样式            topBorderStyle.setBorderTop(borderStyle);            // 上边框颜色            topBorderStyle.setTopBorderColor(IndexedColors.RED.getIndex());            cell.setCellValue("设置上边框(" + borderStyle.name() + ")");            cell.setCellStyle(topBorderStyle);            sheet.setColumnWidth(cellIndex, 35 * 256 + 185);            cellIndex += 2;            // 第三列            HSSFCell cell2 = row.createCell(cellIndex);            HSSFCellStyle bottomBorderStyle = workbook.createCellStyle();            // 下边框样式            bottomBorderStyle.setBorderBottom(borderStyle);            // 下边框颜色            bottomBorderStyle.setBottomBorderColor(IndexedColors.GREEN.getIndex());            cell2.setCellValue("设置下边框(" + borderStyle.name() + ")");            cell2.setCellStyle(bottomBorderStyle);            sheet.setColumnWidth(cellIndex, 35 * 256 + 185);            cellIndex += 2;            // 第五列            HSSFCell cell3 = row.createCell(cellIndex);            HSSFCellStyle leftBorderStyle = workbook.createCellStyle();            // 左边框样式            leftBorderStyle.setBorderLeft(borderStyle);            // 左边框颜色            leftBorderStyle.setLeftBorderColor(IndexedColors.YELLOW.getIndex());            cell3.setCellValue("设置左边框(" + borderStyle.name() + ")");            cell3.setCellStyle(leftBorderStyle);            sheet.setColumnWidth(cellIndex, 35 * 256 + 185);            cellIndex += 2;            // 第七列            HSSFCell cell4 = row.createCell(cellIndex);            HSSFCellStyle rightBorderStyle = workbook.createCellStyle();            // 左边框样式            rightBorderStyle.setBorderRight(borderStyle);            // 右边框颜色            rightBorderStyle.setRightBorderColor(IndexedColors.ORANGE.getIndex());            cell4.setCellValue("设置右边框(" + borderStyle.name() + ")");            cell4.setCellStyle(rightBorderStyle);            sheet.setColumnWidth(cellIndex, 35 * 256 + 185);        }        FileOutputStream outputStream = new FileOutputStream("D:/temp/Excel单元格边框样式.xlsx");        workbook.write(outputStream);        outputStream.close();        workbook.close();    }

边框样式对照表，括号内为BorderStyle枚举对象

附一：一些问题

1、关于列宽使用磅*20的计算方式

2、关于行高使用磅*256+185的计算方式

3、关于sheet.getLastRowNum()最终行数不正确问题

如果整个Excel中存在空行（整行空），当时若干空行下面存在其他数据，这时候获取到的最终行号就不对了，尤其是存在合并单元格的情况最容易出现这类问题。

很明显10、11、13、14全都是空行了，这时候的lastNum就是不正确的，这种情况要尤为注意。

避免这种情况的出现最直接的一种方式就是，预先知道数据存在多少行，先把所有行都生成sheet.createRow(0)。

同样地，空白的单元格也会出现这种情况，如果单元格不存在或没有样式，获取到的最后一个单元格列数也是不正确的。

4、idea中按住快捷键（Shift）+鼠标悬浮到对应单词可以查看颜色

附二：参考链接

像素、磅、点、缇等各种单位换算_点和像素换算_tanghuan的博客-CSDN博客
JAVA对excle创建、读取、设置单元格颜色、背景色、跨行跨列_java设置excel背景色_谷同学的博客-CSDN博客
POI4颜色名称，颜色汉语名称，颜色对应关系_软件工程师文艺的博客-CSDN博客
POI设置Excel单元格背景色（setFillForegroundColor与setFillPattern的使用） - 大墨垂杨 - 博客园
java用POI设置Excel的列宽_sheet.setcolumnwidth_duqian42707的博客-CSDN博客
Java POI 设置Excel单元格的宽度和高度_java poi 设置单元格宽度_aosica的博客-CSDN博客

来源地址：https://blog.csdn.net/dongzi_yu/article/details/131577857