[移动开发]Android poi工具类 只关注数据，抽象出写入细节

Android poi工具类 只关注数据，抽象出写入细节

使用poi excel类库

添加依赖
//poi excel
implementation ‘org.apache.poi:poi-scratchpad:3.15-beta2’

ExcelUtil

import org.apache.poi.hssf.usermodel.HSSFBorderFormatting;
import org.apache.poi.hssf.usermodel.HSSFCell;
import org.apache.poi.hssf.usermodel.HSSFCellStyle;
import org.apache.poi.hssf.usermodel.HSSFFont;
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.hssf.util.HSSFColor;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.List;
import java.util.Map;
import java.util.Set;

public class ReortFormUtil {

    private ExcelUtil() {

    }

    private static ExcelUtil instance = new ExcelUtil();

    public static ExcelUtil getInstance() {

        return instance;

    }

    /**
     * @param heads    标题数据
     * @param logs     本体数据
     * @param fileName 文件名
     */
    public void makeExcel(List<String> heads, Map<Integer, Map<Integer, String>> logs, String path,String fileName) {

        HSSFWorkbook wb = new HSSFWorkbook();

        HSSFSheet sheet = wb.createSheet();

        createExcelHead(wb, sheet, heads);

        createBody(wb, sheet, heads.size(), logs);

        createFile(wb,path,fileName);
    }

    /**
     * @param wb    工作簿
     * @param sheet sheet表
     * @param heads 标题数据
     * @apiNote 创建excel标题数据
     */
    private void createExcelHead(HSSFWorkbook wb, HSSFSheet sheet, List<String> heads) {

        HSSFRow row = sheet.createRow(0);

        //设置单元格样式
        HSSFCellStyle titleStyle = wb.createCellStyle(); //标题

        HSSFFont titleFont = wb.createFont(); //标题字体

        titleFont.setFontHeightInPoints((short) 12); //字号

        titleStyle.setFont(titleFont);

        titleStyle.setAlignment(HSSFCellStyle.ALIGN_CENTER);

        titleStyle.setFillPattern(HSSFCellStyle.SOLID_FOREGROUND);

        titleStyle.setFillForegroundColor(HSSFColor.GOLD.index);

        titleStyle.setBorderBottom(HSSFBorderFormatting.BORDER_THIN);

        titleStyle.setBorderTop(HSSFBorderFormatting.BORDER_THIN);

        titleStyle.setBorderLeft(HSSFBorderFormatting.BORDER_THIN);

        titleStyle.setBorderRight(HSSFBorderFormatting.BORDER_THIN);

        for (int i = 0; i < heads.size(); i++) {

            HSSFCell cell = row.createCell(i);

            cell.setCellStyle(titleStyle);

            cell.setCellValue(heads.get(i));

        }
    }

    /**
     * @param wb        工作簿
     * @param sheet     sheet表
     * @param titleSize 标题数量
     * @param logs      第一个key 代表每一行  第二个key代表一行中的每列  最后的String为填入的数据
     * @apiNote 生成excel本体数据
     */
    private void createBody(HSSFWorkbook wb, HSSFSheet sheet, int titleSize, Map<Integer, Map<Integer, String>> logs) {

        HSSFCellStyle bodyStyle = wb.createCellStyle();

        HSSFFont bodyFont = wb.createFont();

        bodyFont.setFontHeightInPoints((short) 10);

        bodyStyle.setFont(bodyFont);

        bodyStyle.setAlignment(HSSFCellStyle.ALIGN_CENTER);

        bodyStyle.setFillPattern(HSSFCellStyle.SOLID_FOREGROUND);

        bodyStyle.setFillForegroundColor(HSSFColor.GREY_25_PERCENT.index);

        bodyStyle.setBorderBottom(HSSFBorderFormatting.BORDER_THIN);

        bodyStyle.setBorderTop(HSSFBorderFormatting.BORDER_THIN);

        bodyStyle.setBorderLeft(HSSFBorderFormatting.BORDER_THIN);

        bodyStyle.setBorderRight(HSSFBorderFormatting.BORDER_THIN);

        for (int i = 0; i < logs.size(); i++) {

            HSSFRow hssfRow = sheet.createRow(i+1);

            Map<Integer, String> maps = logs.get(i);

            Set<Integer> cells = maps.keySet();

            for (Integer key : cells) {

                HSSFCell cell = hssfRow.createCell(key);

                String data = maps.get(key);

                cell.setCellStyle(bodyStyle);

                cell.setCellValue(data);

                sheet.setColumnWidth(key,(data.getBytes().length+8)* 256 );
            }
        }
    }

    /**
     * @param wb       工作簿
     * @param fileName 文件名
     * @apiNote 写入文件到本地存储
     */
    private void createFile(HSSFWorkbook wb, String path,String fileName) {

        FileOutputStream output = null;

        File file = new File(path);

        if (!file.exists()) {

            System.out.println("createNewExcel: 文件夹不存在，开始创建");

            file.mkdir();

        } else {

            System.out.println("createNewExcel: 文件夹已存在");

        }
        try {

            output = new FileOutputStream(path+"/"+fileName);

            wb.write(output);

        } catch (Exception e) {

            e.printStackTrace();

        } finally {

            try {

                output.flush();

                output.close();

            } catch (IOException e) {

                e.printStackTrace();

            }
        }
    }
}

注意事项
1：文件读写权限
2：标题中的list数据顺序与body的map相互对应
3：poi库各版本间api存在差异，如修改依赖库版本，会出现不兼容问题