Java实现Excel样式设置的详细方法

import org.apache.poi.ss.usermodel.*;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
import org.apache.poi.xssf.usermodel.IndexedColorMap;
import org.apache.poi.xssf.usermodel.XSSFColor;
import java.io.FileOutputStream;
import java.io.IOException;

public class ExcelStyleDemo {

    public static void main(String[] args) {
        try (Workbook workbook = new XSSFWorkbook()) {
            Sheet sheet = workbook.createSheet("样式示例");

            // 创建一个单元格
            Row row = sheet.createRow(0);
            Cell cell = row.createCell(0);
            cell.setCellValue("Hello Styled Cell!");

            // 创建一个样式对象
            CellStyle style = workbook.createCellStyle();

            // 设置字体
            Font font = workbook.createFont();
            font.setFontHeightInPoints((short) 14); // 字号
            font.setColor(IndexedColors.RED.getIndex()); // 字体颜色
            font.setBold(true); // 加粗
            style.setFont(font);

            // 设置背景色
            style.setFillForegroundColor(IndexedColors.LIGHT_YELLOW.getIndex()); // 前景色
            style.setFillPattern(FillPatternType.SOLID_FOREGROUND); // 填充模式

            // 应用样式到单元格
            cell.setCellStyle(style);

            // 另一个单元格，演示对齐
            Cell cell2 = row.createCell(1);
            cell2.setCellValue("居中对齐");
            CellStyle style2 = workbook.createCellStyle();
            style2.setAlignment(HorizontalAlignment.CENTER); // 水平居中
            style2.setVerticalAlignment(VerticalAlignment.CENTER); // 垂直居中
            style2.setWrapText(true); // 自动换行
            cell2.setCellStyle(style2);

            // 写入文件
            try (FileOutputStream fileOut = new FileOutputStream("styled_excel.xlsx")) {
                workbook.write(fileOut);
                System.out.println("Excel文件已生成：styled_excel.xlsx");
            }

        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

// 获取或创建字体对象
Font headerFont = workbook.createFont();
headerFont.setFontName("Arial"); // 字体名称
headerFont.setFontHeightInPoints((short) 12); // 字号
headerFont.setColor(IndexedColors.BLUE.getIndex()); // 字体颜色，例如蓝色
headerFont.setBold(true); // 加粗
headerFont.setItalic(true); // 斜体

// 将字体应用到样式
CellStyle headerStyle = workbook.createCellStyle();
headerStyle.setFont(headerFont);

CellStyle backgroundStyle = workbook.createCellStyle();
backgroundStyle.setFillForegroundColor(IndexedColors.PALE_BLUE.getIndex()); // 浅蓝色背景
backgroundStyle.setFillPattern(FillPatternType.SOLID_FOREGROUND);

CellStyle alignmentStyle = workbook.createCellStyle();
alignmentStyle.setAlignment(HorizontalAlignment.LEFT); // 水平左对齐
alignmentStyle.setVerticalAlignment(VerticalAlignment.TOP); // 垂直顶部对齐
alignmentStyle.setWrapText(true); // 自动换行

CellStyle borderStyle = workbook.createCellStyle();

// 设置所有边框为细线
borderStyle.setBorderTop(BorderStyle.THIN);
borderStyle.setBorderBottom(BorderStyle.THIN);
borderStyle.setBorderLeft(BorderStyle.THIN);
borderStyle.setBorderRight(BorderStyle.THIN);

// 设置边框颜色为黑色
borderStyle.setTopBorderColor(IndexedColors.BLACK.getIndex());
borderStyle.setBottomBorderColor(IndexedColors.BLACK.getIndex());
borderStyle.setLeftBorderColor(IndexedColors.BLACK.getIndex());
borderStyle.setRightBorderColor(IndexedColors.BLACK.getIndex());

// 示例：一个带有边框和深色背景的单元格
CellStyle specialCellStyle = workbook.createCellStyle();

// 边框
specialCellStyle.setBorderTop(BorderStyle.MEDIUM);
specialCellStyle.setBorderBottom(BorderStyle.MEDIUM);
specialCellStyle.setBorderLeft(BorderStyle.MEDIUM);
specialCellStyle.setBorderRight(BorderStyle.MEDIUM);
specialCellStyle.setTopBorderColor(IndexedColors.DARK_BLUE.getIndex());
specialCellStyle.setBottomBorderColor(IndexedColors.DARK_BLUE.getIndex());
specialCellStyle.setLeftBorderColor(IndexedColors.DARK_BLUE.getIndex());
specialCellStyle.setRightBorderColor(IndexedColors.DARK_BLUE.getIndex());

// 背景色
specialCellStyle.setFillForegroundColor(IndexedColors.GREY_25_PERCENT.getIndex()); // 25%灰色
specialCellStyle.setFillPattern(FillPatternType.SOLID_FOREGROUND);

// 字体（通常背景色深，字体要亮）
Font whiteFont = workbook.createFont();
whiteFont.setColor(IndexedColors.WHITE.getIndex());
whiteFont.setBold(true);
specialCellStyle.setFont(whiteFont);

// 假设有一个方法来获取或创建样式
public CellStyle getOrCreateCellStyle(Workbook workbook, String styleKey, CellStyleCreator creator) {
    if (styleCache.containsKey(styleKey)) {
        return styleCache.get(styleKey);
    }
    CellStyle newStyle = creator.create(workbook);
    styleCache.put(styleKey, newStyle);
    return newStyle;
}

// 示例用法：
// 定义一个接口来创建样式
interface CellStyleCreator {
    CellStyle create(Workbook workbook);
}

// 在使用时，根据需要定义不同的creator
CellStyle headerStyle = getOrCreateCellStyle(workbook, "headerStyle", wb -> {
    CellStyle s = wb.createCellStyle();
    Font f = wb.createFont();
    f.setBold(true);
    f.setFontHeightInPoints((short) 12);
    s.setFont(f);
    s.setAlignment(HorizontalAlignment.CENTER);
    return s;
});