多sheet的Excel工具类（通过注解类生成Excel文件）

ExportExcelUtil类

package com.ml.support.excel;

import com.google.common.base.Strings;
import com.google.common.collect.Lists;
import com.google.common.collect.Maps;
import com.google.common.collect.Sets;
import com.ml.support.core.BusinessException;
import com.ml.support.core.ErrorCode;
import com.ml.support.utils.Reflections;
import lombok.Getter;
import lombok.extern.slf4j.Slf4j;
import org.apache.commons.lang3.StringUtils;
import org.apache.poi.ss.usermodel.*;
import org.apache.poi.ss.util.CellRangeAddress;
import org.apache.poi.xssf.streaming.SXSSFWorkbook;
import org.apache.poi.xssf.usermodel.XSSFClientAnchor;
import org.apache.poi.xssf.usermodel.XSSFRichTextString;

import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.lang.reflect.Field;
import java.lang.reflect.Method;
import java.math.BigDecimal;
import java.util.*;

import static org.apache.poi.ss.usermodel.HorizontalAlignment.*;


@Slf4j @Getter
public class ExcelMoreSheetUtil {
    /**
     * 工作薄对象
     */
    private Workbook wb;

    /**
     * 样式列表
     */
    private Map styles;

    Map rownumMap = new LinkedHashMap<>();

    /**
     * 拥有合并单元格的行
     */
    private Set mergedRows = Sets.newHashSet();

    /**
     * key 为sheetName
     * value 为表头标题
     */
    Map> headerMap = new HashMap<>();
    /**
     * key 为sheetName
     * value 为数据集
     */
    Map> annotationMap = new LinkedHashMap<>();

    /**
     * @param isAutoCreateHeader 只能创建单行标题
     */
    public ExcelMoreSheetUtil(Map> clsMap, int type, boolean isAutoCreateHeader, int... groups) {
        //遍历多个sheet
        for (Map.Entry> entry : clsMap.entrySet()) {
            List annotationList = Lists.newArrayList();
            String sheetName = entry.getKey();
            Class cls = entry.getValue();
            // Get annotation statisfield
            Field[] fs = cls.getDeclaredFields();
            for (Field f : fs) {
                ExcelField ef = f.getAnnotation(ExcelField.class);
                if (ef != null && (ef.type() == 0 || ef.type() == type)) {
                    if (groups != null && groups.length > 0) {
                        boolean inGroup = false;
                        for (int g : groups) {
                            if (inGroup) {
                                break;
                            }
                            for (int efg : ef.groups()) {
                                if (g == efg) {
                                    inGroup = true;
                                    annotationList.add(new Object[]{ef, f});
                                    break;
                                }
                            }
                        }
                    } else {
                        annotationList.add(new Object[]{ef, f});
                    }
                }
            }
            // Get annotation method
            Method[] ms = cls.getDeclaredMethods();
            for (Method m : ms) {
                ExcelField ef = m.getAnnotation(ExcelField.class);
                if (ef != null && (ef.type() == 0 || ef.type() == type)) {
                    if (groups != null && groups.length > 0) {
                        boolean inGroup = false;
                        for (int g : groups) {
                            if (inGroup) {
                                break;
                            }
                            for (int efg : ef.groups()) {
                                if (g == efg) {
                                    inGroup = true;
                                    annotationList.add(new Object[]{ef, m});
                                    break;
                                }
                            }
                        }
                    } else {
                        annotationList.add(new Object[]{ef, m});
                    }
                }
            }
            // Field sorting
            Collections.sort(annotationList, new Comparator() {
                public int compare(Object[] o1, Object[] o2) {
                    return new Integer(((ExcelField) o1[0]).sort()).compareTo(
                        new Integer(((ExcelField) o2[0]).sort()));
                }
            });
            // Initialize
            List headerList = Lists.newArrayList();
            for (Object[] os : annotationList) {
                String t = ((ExcelField) os[0]).title();
                // 如果是导出，则去掉注释
                if (type == 1) {
                    String[] ss = StringUtils.split(t, "**", 2);
                    if (ss.length == 2) {
                        t = ss[0];
                    }
                }
                headerList.add(t);
            }

            // 能否在此处理数据
            headerMap.put(sheetName, headerList);
            annotationMap.put(sheetName, annotationList);
        }

        if (isAutoCreateHeader) createHeader();
    }

    /**
     * 创建头部
     */
    public void createHeader() {
        if (this.wb == null) {
            this.wb = new SXSSFWorkbook(500);
        }
        //遍历map创建响应的sheet
        for (Map.Entry> entry : headerMap.entrySet()) {
            int rownum = 0;
            String key = entry.getKey();
            List headerList = entry.getValue();
            Sheet sheet = wb.getSheet(key);
            if (sheet == null) {
                sheet = wb.createSheet(key);
            }
            this.styles = createStyles(wb);
            // add title
            if (StringUtils.isNotBlank(key)) {
                Row titleRow = sheet.createRow(rownum++);
                titleRow.setHeightInPoints(30);
                Cell titleCell = titleRow.createCell(0);
                titleCell.setCellStyle(styles.get("title"));
                titleCell.setCellValue(key);
                sheet.addMergedRegion(new CellRangeAddress(titleRow.getRowNum(),
                    titleRow.getRowNum(), titleRow.getRowNum(), headerList.size() - 1));
            }
            // Create header
            if (headerList == null) {
                throw new BusinessException(ErrorCode.ERR_20604);
            }
            Row headerRow = sheet.createRow(rownum++);
            headerRow.setHeightInPoints(16);
            for (int i = 0; i < headerList.size(); i++) {
                Cell cell = headerRow.createCell(i);
                cell.setCellStyle(styles.get("header"));
                String[] ss = StringUtils.split(headerList.get(i), "**", 2);
                if (ss.length == 2) {
                    cell.setCellValue(ss[0]);
                    Comment comment = sheet.createDrawingPatriarch().createCellComment(
                        new XSSFClientAnchor(0, 0, 0, 0, (short) 3, 3, (short) 5, 6));
                    comment.setString(new XSSFRichTextString(ss[1]));
                    cell.setCellComment(comment);
                } else {
                    cell.setCellValue(headerList.get(i));
                }
//                sheet.autoSizeColumn(i);
            }
            for (int i = 0; i < headerList.size(); i++) {
                int colWidth = sheet.getColumnWidth(i) * 2;
                sheet.setColumnWidth(i, colWidth < 3000 ? 3000 : colWidth);
            }
            rownumMap.put(key, rownum);
        }
    }

    /**
     * 添加数据（通过annotation.ExportField添加数据）
     *
     * @return dataMap 数据列表,用于注解解析
     */
    public  ExcelMoreSheetUtil setDataSource(Map> dataMap) {
        int rownum;
        for (Map.Entry> entry : dataMap.entrySet()) {
            String sheetName = entry.getKey();//sheet名称
            rownum = rownumMap.get(sheetName);//获取本sheet的row行数
            //根据sheet名称获取sheet对象
            Sheet fileSheet = getSheet(sheetName);
            List list = entry.getValue();
            for (E e : list) {
                int colunm = 0;
                Row row = fileSheet.createRow(rownum++);
                StringBuilder sb = new StringBuilder();
                List annotationList = annotationMap.get(sheetName);
                for (Object[] os : annotationList) {
                    ExcelField ef = (ExcelField) os[0];
                    Object val = null;
                    // Get entity value
                    try {
                        if (StringUtils.isNotBlank(ef.value())) {
                            val = Reflections.invokeGetter(e, ef.value());
                        } else {
                            if (os[1] instanceof Field) {
                                val = Reflections.invokeGetter(e, ((Field) os[1]).getName());
                            } else if (os[1] instanceof Method) {
                                val = Reflections.invokeMethod(e, ((Method) os[1]).getName(), new Class[]{}, new Object[]{});
                            }
                        }
                        // If is dict, get dict label
                        if (StringUtils.isNotBlank(ef.dictType())) {
                            //val = DictUtils.getDictLabel(val == null ? "" : val.toString(), ef.dictType(), "");
                        }
                    } catch (Exception ex) {
                        // Failure to ignore
                        val = "";
                    }
                    this.addCell(row, colunm++, val, ef.align(), ef.fieldType());
                    sb.append(val + ", ");
                }
            }
        }
        return this;
    }

    /**
     * 创建表格样式
     *
     * @param wb 工作薄对象
     * @return 样式列表
     */
    private Map createStyles(Workbook wb) {
        Map styles = Maps.newHashMap();

        CellStyle style = wb.createCellStyle();
        style.setAlignment(CENTER);
        style.setVerticalAlignment(VerticalAlignment.CENTER);
        Font titleFont = wb.createFont();
        titleFont.setFontName("Arial");
        titleFont.setFontHeightInPoints((short) 16);
        titleFont.setBold(true);
        style.setFont(titleFont);
        styles.put("title", style);

        style = wb.createCellStyle();
        style.setVerticalAlignment(VerticalAlignment.CENTER);
        style.setBorderRight(BorderStyle.THIN);
        style.setRightBorderColor(IndexedColors.GREY_50_PERCENT.getIndex());
        style.setBorderLeft(BorderStyle.THIN);
        style.setLeftBorderColor(IndexedColors.GREY_50_PERCENT.getIndex());
        style.setBorderTop(BorderStyle.THIN);
        style.setTopBorderColor(IndexedColors.GREY_50_PERCENT.getIndex());
        style.setBorderBottom(BorderStyle.THIN);
        style.setBottomBorderColor(IndexedColors.GREY_50_PERCENT.getIndex());
        Font dataFont = wb.createFont();
        dataFont.setFontName("Arial");
        dataFont.setFontHeightInPoints((short) 10);
        style.setFont(dataFont);
        styles.put("data", style);

        style = wb.createCellStyle();
        style.cloneStyleFrom(styles.get("data"));
        style.setAlignment(LEFT);
        styles.put("data1", style);

        style = wb.createCellStyle();
        style.cloneStyleFrom(styles.get("data"));
        style.setAlignment(CENTER);
        styles.put("data2", style);

        style = wb.createCellStyle();
        style.cloneStyleFrom(styles.get("data"));
        style.setAlignment(RIGHT);
        styles.put("data3", style);

        style = wb.createCellStyle();
        style.cloneStyleFrom(styles.get("data"));
//        style.setWrapText(true);
        style.setAlignment(CENTER);
        style.setFillForegroundColor(IndexedColors.WHITE.getIndex());//单元格背景颜色
        style.setFillPattern(FillPatternType.SOLID_FOREGROUND);
        Font headerFont = wb.createFont();
        headerFont.setFontName("Arial");
        headerFont.setFontHeightInPoints((short) 10);
        headerFont.setBold(true);//单元格内字体颜色
        headerFont.setColor(IndexedColors.BLACK.getIndex());
        style.setFont(headerFont);
        styles.put("header", style);

        return styles;
    }

    /**
     * 添加一个单元格
     *
     * @param row    添加的行
     * @param column 添加列号
     * @param val    添加值
     * @param align  对齐方式（1：靠左；2：居中；3：靠右）
     * @return 单元格对象
     */
    public Cell addCell(Row row, int column, Object val, int align, Class fieldType) {
        Cell cell = row.createCell(column);
        String cellFormatString = "@";
        try {
            if (val == null) {
                val = "";
            } else if (fieldType != Class.class) {
                cell.setCellValue((String) fieldType.getMethod("setValue", Object.class).invoke(null, val));
            } else {
                if (val instanceof String) {
                    cell.setCellValue((String) val);
                } else if (val instanceof Integer) {
                    cell.setCellValue((Integer) val);
                    cellFormatString = "0";
                } else if (val instanceof Long) {
                    cell.setCellValue((Long) val);
                    cellFormatString = "0";
                } else if (val instanceof Double) {
                    cell.setCellValue((Double) val);
                    cellFormatString = "0.00";
                } else if (val instanceof BigDecimal) {
                    cell.setCellValue(((BigDecimal) val).doubleValue());
                } else if (val instanceof Float) {
                    cell.setCellValue((Float) val);
                    cellFormatString = "0.00";
                } else if (val instanceof Date) {
                    cell.setCellValue((Date) val);
                    cellFormatString = "yyyy-MM-dd HH:mm";
                } else {
                    cell.setCellValue((String) Class.forName(this.getClass().getName().replaceAll(this.getClass().getSimpleName(),
                        "fieldtype." + val.getClass().getSimpleName() + "Type")).getMethod("setValue", Object.class).invoke(null, val));
                }
            }
            if (val != null) {
                if (styles == null) this.styles = createStyles(wb);
                CellStyle style = styles.get("data_column_" + column);
                if (style == null) {
                    style = wb.createCellStyle();
                    style.cloneStyleFrom(styles.get("data" + (align >= 1 && align <= 3 ? align : "")));
                    if (!Strings.isNullOrEmpty(cellFormatString)) {
                        style.setDataFormat(wb.createDataFormat().getFormat(cellFormatString));
                    }
                    styles.put("data_column_" + column, style);
                }
                cell.setCellStyle(style);
            }
        } catch (Exception ex) {
            cell.setCellValue(val.toString());
        }
        return cell;
    }

    /**
     * 根据sheet名称获取sheet
     */
    public Sheet getSheet(String sheetName) {
        Sheet sheet = wb.getSheet(sheetName);
        return sheet;
    }

    /**
     * 输出数据流
     *
     * @param os 输出数据流
     */
    public ExcelMoreSheetUtil write(OutputStream os) throws IOException {
        wb.write(os);
        return this;
    }

    /**
     * 输出到文件
     */
    public ExcelMoreSheetUtil writeFile(String name) throws IOException {
        FileOutputStream os = new FileOutputStream(name);
        this.write(os);
        return this;
    }
}

注解类：

@Target({ElementType.METHOD, ElementType.FIELD, ElementType.TYPE})
@Retention(RetentionPolicy.RUNTIME)
public @interface ExcelField {

   /**
    * 导出字段名（默认调用当前字段的“get”方法，如指定导出字段为对象，请填写“对象名.对象属性”，例：“area.name”、“office.name”）
    */
   String value() default "";
   
   /**
    * 导出字段标题（需要添加批注请用“**”分隔，标题**批注，仅对导出模板有效）
    */
   String title();
   
   /**
    * 字段类型（0：导出导入；1：仅导出；2：仅导入）
    */
   int type() default 0;

   /**
    * 导出字段对齐方式（0：自动；1：靠左；2：居中；3：靠右）
    */
   int align() default 0;
   
   /**
    * 导出字段字段排序（升序）
    */
   int sort() default 0;

   /**
    * 如果是字典类型，请设置字典的type值
    */
   String dictType() default "";
   
   /**
    * 反射类型
    */
   Class fieldType() default Class.class;
   
   /**
    * 字段归属组（根据分组导出导入）
    */
   int[] groups() default {};
}

测试例子：

Map> clsMap = new LinkedHashMap>();
clsMap.put("sheetName1", BaseAdmissionsStudentsInput.class);
clsMap.put("sheetName2", BaseAdmissionsStudentsInput.class);

Map> dataSource = new LinkedHashMap>();
//sheet1数据
List cusAccount = Lists.newArrayList();
BaseAdmissionsStudentsInput input = new BaseAdmissionsStudentsInput();
input.setUnitName("单位1");
cusAccount.add(input);
dataSource.put("sheetName1", cusAccount);

//sheet2数据
List cusRatio = Lists.newArrayList();
BaseAdmissionsStudentsInput input2 = new BaseAdmissionsStudentsInput();
input2.setUnitName("单位2");
cusRatio.add(input2);
dataSource.put("sheetName2", cusRatio);

ExcelMoreSheetUtil excelUtil = new ExcelMoreSheetUtil(clsMap, 1, true).setDataSource(dataSource);
try {
    excelUtil.writeFile("C:/file/template/测试sheet模板.xlsx");
} catch (IOException e) {
    e.printStackTrace();
}