easypoi exports Excel report (the report is stored in Aliyun OSS and returns to the front-end path)

1. Import dependencies

<!-- easypoi -->
<dependency>
	<groupId>cn.afterturn</groupId>
	<artifactId>easypoi-base</artifactId>
	<version>4.4.0</version>
</dependency>
<dependency>
    <groupId>cn.afterturn</groupId>
	<artifactId>easypoi-annotation</artifactId>
	<version>4.4.0</version>
</dependency>

2. Single header Excel

1. controller layer

@GetMapping("/export/studentExcel")
public ResponseEntity exportStudentExcel(){
    return ResponseEntity.ok(studentService.exportStudentExcel());
}

2. service layer

public String exportDataDownload() {
        // Excel表的参数——title、sheetName、ExcelType
        ExportParams exportParams = new ExportParams("学生表", "学生表", ExcelType.XSSF);

        // Excel表的样式，可实现IExcelExportStyler接口自定义
        exportParams.setStyle(ExcelStyleUtil.class);

        // 表头ExcelExportEntity(name,key,width)的集合
        List<ExcelExportEntity> entityList = new ArrayList<>();
        ExcelExportEntity stuNumEntity = new ExcelExportEntity("学号", "stuNum", 10);
        entityList.add(stuNumEntity);
        ExcelExportEntity stuNameEntity = new ExcelExportEntity("姓名", "stuName", 30);
        entityList.add(stuNameEntity);
        ExcelExportEntity gradeEntity = new ExcelExportEntity("年级", "grade", 20);
        // 列的合并
        // gradeEntity.setMergeVertical(true);
        entityList.add(gradeEntity);

        // 表体-Map集合，Map的key要和表头中的key对应
        List<Map<String, Object>> dataList = new ArrayList<>();
        Map<String, Object> stu1 = new HashMap<>();
        stu1.put("stuNum", "4184002223");
        stu1.put("stuName", "酉曲豆");
        stu1.put("grade", 3);
        dataList.add(stu1);
        Map<String, Object> stu2 = new HashMap<>();
        stu2.put("stuNum", "4184002222");
        stu2.put("stuName", "夏禾");
        stu2.put("grade", 6);
        dataList.add(stu2);

        // 生成Workbook对象
        Workbook workbook = ExcelExportUtil.exportExcel(exportParams, entityList, dataList);
        return fileService.getFilePath("学生表.xlsx", workbook);
    }

3.ExcelStyleUtil (style example) and fileService.getFilePath() method

 ExcelStyleUtil：

public class ExcelStyleUtil implements IExcelExportStyler {
	private static final short STRING_FORMAT = (short) BuiltinFormats.getBuiltinFormat("TEXT");
	private static final short FONT_SIZE_TEN = 9;
	private static final short FONT_SIZE_ELEVEN = 10;
	private static final short FONT_SIZE_TWELVE = 10;
	/**
	 * 大标题样式
	 */
	private CellStyle headerStyle;
	/**
	 * 每列标题样式
	 */
	private CellStyle titleStyle;
	/**
	 * 数据行样式
	 */
	private CellStyle styles;

	public ExcelStyleUtil(Workbook workbook) {
		this.init(workbook);
	}

	/**
	 * 初始化样式
	 *
	 * @param workbook
	 */
	private void init(Workbook workbook) {
		this.headerStyle = initHeaderStyle(workbook);
		this.titleStyle = initTitleStyle(workbook);
		this.styles = initStyles(workbook);
	}

	/**
	 * 大标题样式
	 *
	 * @param color
	 * @return
	 */
	@Override
	public CellStyle getHeaderStyle(short color) {
		return headerStyle;
	}

	/**
	 * 每列标题样式
	 *
	 * @param color
	 * @return
	 */
	@Override
	public CellStyle getTitleStyle(short color) {
		return titleStyle;
	}

	/**
	 * 数据行样式
	 *
	 * @param parity 可以用来表示奇偶行
	 * @param entity 数据内容
	 * @return 样式
	 */
	@Override
	public CellStyle getStyles(boolean parity, ExcelExportEntity entity) {
		return styles;
	}

	/**
	 * 获取样式方法
	 *
	 * @param dataRow 数据行
	 * @param obj     对象
	 * @param data    数据
	 */
	@Override
	public CellStyle getStyles(Cell cell, int dataRow, ExcelExportEntity entity, Object obj, Object data) {
		return getStyles(true, entity);
	}

	/**
	 * 模板使用的样式设置
	 */
	@Override
	public CellStyle getTemplateStyles(boolean isSingle, ExcelForEachParams excelForEachParams) {
		return null;
	}

	/**
	 * 初始化--大标题样式
	 *
	 * @param workbook
	 * @return
	 */
	private CellStyle initHeaderStyle(Workbook workbook) {
		CellStyle style = getBaseCellStyle(workbook);
		style.setFont(getFont(workbook, FONT_SIZE_TWELVE, true));
		return style;
	}

	/**
	 * 初始化--每列标题样式
	 *
	 * @param workbook
	 * @return
	 */
	private CellStyle initTitleStyle(Workbook workbook) {
		CellStyle style = getBaseCellStyle(workbook);
		style.setFont(getFont(workbook, FONT_SIZE_ELEVEN, false));
		//背景色
		style.setFillForegroundColor(IndexedColors.GREY_25_PERCENT.getIndex());
		style.setFillPattern(FillPatternType.SOLID_FOREGROUND);
		return style;
	}

	/**
	 * 初始化--数据行样式
	 *
	 * @param workbook
	 * @return
	 */
	private CellStyle initStyles(Workbook workbook) {
		CellStyle style = getBaseCellStyle(workbook);
		style.setFont(getFont(workbook, FONT_SIZE_TEN, false));
		style.setDataFormat(STRING_FORMAT);
		return style;
	}

	/**
	 * 基础样式
	 *
	 * @return
	 */
	private CellStyle getBaseCellStyle(Workbook workbook) {
		CellStyle style = workbook.createCellStyle();
		//下边框
		style.setBorderBottom(BorderStyle.THIN);
		//左边框
		style.setBorderLeft(BorderStyle.THIN);
		//上边框
		style.setBorderTop(BorderStyle.THIN);
		//右边框
		style.setBorderRight(BorderStyle.THIN);
		//水平居中
		style.setAlignment(HorizontalAlignment.CENTER);
		//上下居中
		style.setVerticalAlignment(VerticalAlignment.CENTER);
		//设置自动换行
		style.setWrapText(true);
		return style;
	}

	/**
	 * 字体样式
	 *
	 * @param size   字体大小
	 * @param isBold 是否加粗
	 * @return
	 */
	private Font getFont(Workbook workbook, short size, boolean isBold) {
		Font font = workbook.createFont();
		//字体样式
		font.setFontName("宋体");
		//是否加粗
		font.setBold(isBold);
		//字体大小
		font.setFontHeightInPoints(size);
		return font;
	}
}

fileService.getFilePath()：

@Service
public class FileService {
    // aliyunoss的配置
    @Value("${oss.access_id}")
    private String accessID;
    @Value("${oss.access_key}")
    private String accessKey;
    @Value("${oss.endpoint}")
    private String endPoint;
    @Value("${oss.bucket}")
    protected String bucket;
    @Value("${oss.path}")
    protected String path;

    private OSSClient ossClient;

    public OSSClient getOssClient() {
        if (ossClient == null) {
            ossClient = new OSSClient(endPoint, accessID, accessKey);
        }
        return ossClient;
    }


    public String getFilePath(String fileName, Workbook workbook) {
        InputStream excelStream = null;
        String key = LocalDate.now().toString().replace("-", "") + "/" + fileName;
        String localPath = path + key;
        try {
            ByteArrayOutputStream out = new ByteArrayOutputStream();
            workbook.write(out);
            workbook.close();
            excelStream = new ByteArrayInputStream(out.toByteArray());
            this.getOssClient().putObject(bucket, key, excelStream);
            out.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return localPath;
    }
}

3. Generate Excel according to the Excel template (can meet many specific needs)

The commands supported by EasyPoi are mainly the usage of various fe

• fe: traverse data, create row
• !fe: traverse data without creating row
• $fe: Move down and insert, move the current line and the following lines down. size() line, and then insert
• #fe: Horizontal traversal
• v_fe: horizontal traversal value

The overall style is similar to the el expression, and everyone should be familiar with the way of writing { {}} to represent the expression, and then take the value according to the data in the expression

Regarding the style problem, easypoi will not change the original style of excel. If it is traversal, easypoi will copy it according to the style of the row in the template

For more detailed information, please refer to the official documentation: https://easypoi.mydoc.io/

Use the following picture:

@Test
public void fe_map() throws Exception {
    TemplateExportParams params = new TemplateExportParams(
                "D:\\xxx学校学生模板.xlsx");
    Map<String, Object> map = new HashMap<String, Object>();
    map.put("schoolName", "天神书院");
    map.put("schoolAddress", "九重天");
    map.put("schoolTel", "88888");
    map.put("startDate", "2021-01-01");
    map.put("endDate", "至今");
    List<Map<String, String>> listMap = new ArrayList<Map<String, String>>();
    for (int i = 0; i < 4; i++) {
        Map<String, String> lm = new HashMap<String, String>();
        lm.put("stuNum", "10000" + i);
        lm.put("stuName", "有趣的" + i);
        lm.put("sex", i%2==0 ? "女" : "男");
        lm.put("stuGrade", i);
    }
    map.put("maplist", listMap);

    Workbook workbook = ExcelExportUtil.exportExcel(params, map);
    File savefile = new File("D:/excel/");
    if (!savefile.exists()) {
        savefile.mkdirs();
    }
    FileOutputStream fos = new FileOutputStream("D:/excel/xxx学校学生表.xlsx");
    workbook.write(fos);
    fos.close();
}

4. Generate a multi-sheet Excel based on a single Excel template

        // 引入模板
        // TemplateExportParams templateExportParams = new TemplateExportParams("D:\\门店缺货率测试.xlsx");
        
        // 将所有sheet使用得map进行包装
        Map<Integer, List<Map<String, Object>>> sheetMap = new HashMap<>();

        for (int i = 0;i < 10;i++) {
            List<Map<String, Object>> allMapList = new ArrayList<>();
            Map<String, Object> map = new HashMap<>();
            // 设置sheetName，若不设置该参数，则使用得原本的sheet名称
            map.put("sheetName", "大药店" + i + "号");// 此处填sheet页名称
            // 需与模板文件中字段对应
            map.put("storeName", i + "号店" );
            map.put("saNum", i * 2);
            map.put("sbNum", i * 3);
            map.put("saLackNum", i * 4);
            map.put("sbLackNum", i * 5);
            map.put("saLackRate", i * 0.2);
            map.put("sbLackRate", i * 0.3);
            List<Map<String, String>> mapList = new ArrayList<>();
            for(int j = 1; j <= 5; j++){
                // 创建商品数据
                Map<String,String> skuMap = new HashMap<>();
                skuMap.put("skuNumber", j + "11");
                skuMap.put("sku", j + "22");
                skuMap.put("unit", j + "33");
                skuMap.put("returnFlag", j + "44");
                skuMap.put("level", j + "55");
                skuMap.put("averageSale", j + "66");
                skuMap.put("max", j + "77");
                skuMap.put("mini", j + "88");
                skuMap.put("mouthSale", j + "99");
                skuMap.put("stock", j + "00");
                skuMap.put("turnDays", j + "12");
                skuMap.put("lackStr", j + "13");
                skuMap.put("category", j + "14");
                skuMap.put("replenishmentNum", j + "15");
                mapList.add(skuMap);
            }
            map.put("mapList", mapList);

            allMapList.add(map);
            // 一个sheet页
            sheetMap.put(i, allMapList);
        }
        // 导出excel
        Workbook workbook = ExcelExportUtil.exportExcelClone(sheetMap, templateExportParams);
        return fileService.getFilePath("批量导出门店缺货测试.xlsx",workbook);