Java使用POI导出Excel(一):单sheet

Hanna ·
更新时间:2024-11-13
· 1835 次阅读

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Java使用POI导出Excel(一):单sheet

Java使用POI导出Excel(二):多个sheet

相信在大部分的web项目中都会有导出导入Excel的需求,今天我们就来看看如何用Java代码去实现 用POI导出Excel表格。

一、pom引用

pom文件中,添加以下依赖

 <!--Excel工具--> <dependency> <groupId>org.apache.poi</groupId> <artifactId>poi</artifactId> <version>5.2.2</version> <scope>compile</scope> </dependency> <dependency> <groupId>org.apache.poi</groupId> <artifactId>poi-ooxml</artifactId> <version>5.2.2</version> <scope>compile</scope> </dependency> 二、工具类util 1.ExcelClassField

查看代码

 package com.***; import lombok.Data; import java.util.LinkedHashMap; /** * @description: excel字段 * @author: *** * @date: 2022/6/21 */ @Data public class ExcelClassField { /** * 字段名称 */ private String fieldName; /** * 表头名称 */ private String name; /** * 映射关系 */ private LinkedHashMap<String, String> kvMap; /** * 示例值 */ private Object example; /** * 排序 */ private int sort; /** * 是否为注解字段:0-否,1-是 */ private int hasAnnotation; }  2.ExcelExport(导出Excel用)  package com.***; import java.lang.annotation.ElementType; import java.lang.annotation.Retention; import java.lang.annotation.RetentionPolicy; import java.lang.annotation.Target; /** * @description: excel导出 * @author: *** * @date: 2022/6/21 */ @Target(ElementType.FIELD) @Retention(RetentionPolicy.RUNTIME) public @interface ExcelExport { /** * 字段名称 */ String value(); /** * 导出排序先后: 数字越小越靠前(默认按Java类字段顺序导出) */ int sort() default 0; /** * 导出映射,格式如:0-未知;1-男;2-女 */ String kv() default ""; /** * 导出模板示例值(有值的话,直接取该值,不做映射) */ String example() default ""; } 3.ExcelImport(导入Excel用)  package com.***; import java.lang.annotation.ElementType; import java.lang.annotation.Retention; import java.lang.annotation.RetentionPolicy; import java.lang.annotation.Target; /** * @description: excel导入 * @author: *** * @date: 2022/6/21 */ @Target(ElementType.FIELD) @Retention(RetentionPolicy.RUNTIME) public @interface ExcelImport { /** * 字段名称 */ String value(); /** * 导出映射,格式如:0-未知;1-男;2-女 */ String kv() default ""; /** * 是否为必填字段(默认为非必填) */ boolean required() default false; /** * 最大长度(默认255) */ int maxLength() default 255; /** * 导入唯一性验证(多个字段则取联合验证) */ boolean unique() default false; } 4.ExcelUtils  package com.***; import com.***.utils.DateUtil; import com.alibaba.fastjson.JSONArray; import com.alibaba.fastjson.JSONObject; import com.***.uitl.StringUtils; import org.apache.poi.hssf.usermodel.HSSFDataValidation; import org.apache.poi.hssf.usermodel.HSSFWorkbook; import org.apache.poi.poifs.filesystem.POIFSFileSystem; import org.apache.poi.ss.usermodel.*; import org.apache.poi.ss.usermodel.ClientAnchor.AnchorType; import org.apache.poi.ss.util.CellRangeAddress; import org.apache.poi.ss.util.CellRangeAddressList; import org.apache.poi.xssf.streaming.SXSSFWorkbook; import org.apache.poi.xssf.usermodel.XSSFClientAnchor; import org.apache.poi.xssf.usermodel.XSSFWorkbook; import org.springframework.web.context.request.RequestContextHolder; import org.springframework.web.context.request.ServletRequestAttributes; import org.springframework.web.multipart.MultipartFile; import javax.servlet.ServletOutputStream; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import java.io.*; import java.lang.reflect.Field; import java.math.BigDecimal; import java.math.RoundingMode; import java.net.URL; import java.net.URLEncoder; import java.text.NumberFormat; import java.text.SimpleDateFormat; import java.util.*; import java.util.Map.Entry; import java.util.regex.Pattern; /** * @description: 导出报表util * @author: *** * @date: 2022/6/21 */ public class ExcelUtils { public static final String ROW_MERGE = "row_merge"; public static final String COLUMN_MERGE = "column_merge"; private static final String XLSX = ".xlsx"; private static final String XLS = ".xls"; private static final String DATE_FORMAT = "yyyy-MM-dd HH:mm:ss"; private static final String ROW_NUM = "rowNum"; private static final String ROW_DATA = "rowData"; private static final String ROW_TIPS = "rowTips"; private static final int CELL_OTHER = 0; private static final int CELL_ROW_MERGE = 1; private static final int CELL_COLUMN_MERGE = 2; private static final int IMG_HEIGHT = 30; private static final int IMG_WIDTH = 30; private static final char LEAN_LINE = '/'; private static final int BYTES_DEFAULT_LENGTH = 10240; private static final NumberFormat NUMBER_FORMAT = NumberFormat.getNumberInstance(); public static <T> List<T> readFile(File file, Class<T> clazz) throws Exception { JSONArray array = readFile(file); return getBeanList(array, clazz); } public static <T> List<T> readMultipartFile(MultipartFile mFile, Class<T> clazz) throws Exception { JSONArray array = readMultipartFile(mFile); return getBeanList(array, clazz); } public static JSONArray readFile(File file) throws Exception { return readExcel(null, file); } public static JSONArray readMultipartFile(MultipartFile mFile) throws Exception { return readExcel(mFile, null); } public static Map<String, JSONArray> readFileManySheet(File file) throws Exception { return readExcelManySheet(null, file); } public static Map<String, JSONArray> readFileManySheet(MultipartFile file) throws Exception { return readExcelManySheet(file, null); } private static <T> List<T> getBeanList(JSONArray array, Class<T> clazz) throws Exception { List<T> list = new ArrayList<>(); Map<Integer, String> uniqueMap = new HashMap<>(16); for (int i = 0; i < array.size(); i++) { list.add(getBean(clazz, array.getJSONObject(i), uniqueMap)); } return list; } /** * 获取每个对象的数据 */ private static <T> T getBean(Class<T> c, JSONObject obj, Map<Integer, String> uniqueMap) throws Exception { T t = c.newInstance(); Field[] fields = c.getDeclaredFields(); List<String> errMsgList = new ArrayList<>(); boolean hasRowTipsField = false; StringBuilder uniqueBuilder = new StringBuilder(); int rowNum = 0; for (Field field : fields) { // 行号 if (field.getName().equals(ROW_NUM)) { rowNum = obj.getInteger(ROW_NUM); field.setAccessible(true); field.set(t, rowNum); continue; } // 是否需要设置异常信息 if (field.getName().equals(ROW_TIPS)) { hasRowTipsField = true; continue; } // 原始数据 if (field.getName().equals(ROW_DATA)) { field.setAccessible(true); field.set(t, obj.toString()); continue; } // 设置对应属性值 setFieldValue(t, field, obj, uniqueBuilder, errMsgList); } // 数据唯一性校验 if (uniqueBuilder.length() > 0) { if (uniqueMap.containsValue(uniqueBuilder.toString())) { Set<Integer> rowNumKeys = uniqueMap.keySet(); for (Integer num : rowNumKeys) { if (uniqueMap.get(num).equals(uniqueBuilder.toString())) { errMsgList.add(String.format("数据唯一性校验失败,(%s)与第%s行重复)", uniqueBuilder, num)); } } } else { uniqueMap.put(rowNum, uniqueBuilder.toString()); } } // 失败处理 if (errMsgList.isEmpty() && !hasRowTipsField) { return t; } StringBuilder sb = new StringBuilder(); int size = errMsgList.size(); for (int i = 0; i < size; i++) { if (i == size - 1) { sb.append(errMsgList.get(i)); } else { sb.append(errMsgList.get(i)).append(";"); } } // 设置错误信息 for (Field field : fields) { if (field.getName().equals(ROW_TIPS)) { field.setAccessible(true); field.set(t, sb.toString()); } } return t; } private static <T> void setFieldValue(T t, Field field, JSONObject obj, StringBuilder uniqueBuilder, List<String> errMsgList) { // 获取 ExcelImport 注解属性 ExcelImport annotation = field.getAnnotation(ExcelImport.class); if (annotation == null) { return; } String cname = annotation.value(); if (cname.trim().length() == 0) { return; } // 获取具体值 String val = null; if (obj.containsKey(cname)) { val = getString(obj.getString(cname)); } if (val == null) { return; } field.setAccessible(true); // 判断是否必填 boolean require = annotation.required(); if (require && val.isEmpty()) { errMsgList.add(String.format("[%s]不能为空", cname)); return; } // 数据唯一性获取 boolean unique = annotation.unique(); if (unique) { if (uniqueBuilder.length() > 0) { uniqueBuilder.append("--").append(val); } else { uniqueBuilder.append(val); } } // 判断是否超过最大长度 int maxLength = annotation.maxLength(); if (maxLength > 0 && val.length() > maxLength) { errMsgList.add(String.format("[%s]长度不能超过%s个字符(当前%s个字符)", cname, maxLength, val.length())); } // 判断当前属性是否有映射关系 LinkedHashMap<String, String> kvMap = getKvMap(annotation.kv()); if (!kvMap.isEmpty()) { boolean isMatch = false; for (String key : kvMap.keySet()) { if (kvMap.get(key).equals(val)) { val = key; isMatch = true; break; } } if (!isMatch) { errMsgList.add(String.format("[%s]的值不正确(当前值为%s)", cname, val)); return; } } // 其余情况根据类型赋值 String fieldClassName = field.getType().getSimpleName(); try { if ("String".equalsIgnoreCase(fieldClassName)) { field.set(t, val); } else if ("boolean".equalsIgnoreCase(fieldClassName)) { field.set(t, Boolean.valueOf(val)); } else if ("int".equalsIgnoreCase(fieldClassName) || "Integer".equals(fieldClassName)) { try { field.set(t, Integer.valueOf(val)); } catch (NumberFormatException e) { errMsgList.add(String.format("[%s]的值格式不正确(当前值为%s)", cname, val)); } } else if ("double".equalsIgnoreCase(fieldClassName)) { field.set(t, Double.valueOf(val)); } else if ("long".equalsIgnoreCase(fieldClassName)) { field.set(t, Long.valueOf(val)); } else if ("BigDecimal".equalsIgnoreCase(fieldClassName)) { if (StringUtils.isEmpty(val)) { field.set(t, new BigDecimal(0)); } else { field.set(t, new BigDecimal(val)); } } else if ("Date".equalsIgnoreCase(fieldClassName)) { field.set(t, DateUtil.getDate(val, DateUtil.YYYYMMDDHHMMSS)); } else { field.set(t, val); } } catch (Exception e) { e.printStackTrace(); } } private static Map<String, JSONArray> readExcelManySheet(MultipartFile mFile, File file) throws IOException { Workbook book = getWorkbook(mFile, file); if (book == null) { return Collections.emptyMap(); } Map<String, JSONArray> map = new LinkedHashMap<>(); for (int i = 0; i < book.getNumberOfSheets(); i++) { Sheet sheet = book.getSheetAt(i); JSONArray arr = readSheet(sheet); map.put(sheet.getSheetName(), arr); } book.close(); return map; } private static JSONArray readExcel(MultipartFile mFile, File file) throws IOException { Workbook book = getWorkbook(mFile, file); if (book == null) { return new JSONArray(); } JSONArray array = readSheet(book.getSheetAt(0)); book.close(); return array; } private static Workbook getWorkbook(MultipartFile mFile, File file) throws IOException { boolean fileNotExist = (file == null || !file.exists()); if (mFile == null && fileNotExist) { return null; } // 解析表格数据 InputStream in; String fileName; if (mFile != null) { // 上传文件解析 in = mFile.getInputStream(); fileName = getString(mFile.getOriginalFilename()).toLowerCase(); } else { // 本地文件解析 in = new FileInputStream(file); fileName = file.getName().toLowerCase(); } Workbook book; if (fileName.endsWith(XLSX)) { book = new XSSFWorkbook(in); } else if (fileName.endsWith(XLS)) { POIFSFileSystem poifsFileSystem = new POIFSFileSystem(in); book = new HSSFWorkbook(poifsFileSystem); } else { return null; } in.close(); return book; } private static JSONArray readSheet(Sheet sheet) { // 首行下标 int rowStart = sheet.getFirstRowNum(); // 尾行下标 int rowEnd = sheet.getLastRowNum(); // 获取表头行 Row headRow = sheet.getRow(rowStart); if (headRow == null) { return new JSONArray(); } int cellStart = headRow.getFirstCellNum(); int cellEnd = headRow.getLastCellNum(); Map<Integer, String> keyMap = new HashMap<>(); for (int j = cellStart; j < cellEnd; j++) { // 获取表头数据 String val = getCellValue(headRow.getCell(j)); if (val != null && val.trim().length() != 0) { keyMap.put(j, val); } } // 如果表头没有数据则不进行解析 if (keyMap.isEmpty()) { return (JSONArray) Collections.emptyList(); } // 获取每行JSON对象的值 JSONArray array = new JSONArray(); // 如果首行与尾行相同,表明只有一行,返回表头数据 if (rowStart == rowEnd) { JSONObject obj = new JSONObject(); // 添加行号 obj.put(ROW_NUM, 1); for (int i : keyMap.keySet()) { obj.put(keyMap.get(i), ""); } array.add(obj); return array; } for (int i = rowStart + 1; i <= rowEnd; i++) { Row eachRow = sheet.getRow(i); JSONObject obj = new JSONObject(); // 添加行号 obj.put(ROW_NUM, i + 1); StringBuilder sb = new StringBuilder(); for (int k = cellStart; k < cellEnd; k++) { if (eachRow != null) { String val = getCellValue(eachRow.getCell(k)); // 所有数据添加到里面,用于判断该行是否为空 sb.append(val); obj.put(keyMap.get(k), val); } } if (sb.length() > 0) { array.add(obj); } } return array; } private static String getCellValue(Cell cell) { // 空白或空 if (cell == null || cell.getCellType() == CellType.BLANK) { return ""; } // String类型 if (cell.getCellType() == CellType.STRING) { String val = cell.getStringCellValue(); if (val == null || val.trim().length() == 0) { return ""; } return val.trim(); } // 数字类型 if (cell.getCellType() == CellType.NUMERIC) { String s = cell.getNumericCellValue() + ""; // 去掉尾巴上的小数点0 if (Pattern.matches(".*\\.0*", s)) { return s.split("\\.")[0]; } else { return s.trim(); } } // 布尔值类型 if (cell.getCellType() == CellType.BOOLEAN) { return cell.getBooleanCellValue() + ""; } // 错误类型 return cell.getCellFormula(); } public static <T> void exportTemplate(HttpServletResponse response, String fileName, Class<T> clazz, String dateFormat) { exportTemplate(response, fileName, fileName, clazz, false, dateFormat); } public static <T> void exportTemplate(HttpServletResponse response, String fileName, String sheetName, Class<T> clazz, String dateFormat) { exportTemplate(response, fileName, sheetName, clazz, false, dateFormat); } public static <T> void exportTemplate(HttpServletResponse response, String fileName, Class<T> clazz, boolean isContainExample, String dateFormat) { exportTemplate(response, fileName, fileName, clazz, isContainExample, dateFormat); } public static <T> void exportTemplate(HttpServletResponse response, String fileName, String sheetName, Class<T> clazz, boolean isContainExample, String dateFormat) { // 获取表头字段 List<ExcelClassField> headFieldList = getExcelClassFieldList(clazz); // 获取表头数据和示例数据 List<List<Object>> sheetDataList = new ArrayList<>(); List<Object> headList = new ArrayList<>(); List<Object> exampleList = new ArrayList<>(); Map<Integer, List<String>> selectMap = new LinkedHashMap<>(); for (int i = 0; i < headFieldList.size(); i++) { ExcelClassField each = headFieldList.get(i); headList.add(each.getName()); exampleList.add(each.getExample()); LinkedHashMap<String, String> kvMap = each.getKvMap(); if (kvMap != null && kvMap.size() > 0) { selectMap.put(i, new ArrayList<>(kvMap.values())); } } sheetDataList.add(headList); if (isContainExample) { sheetDataList.add(exampleList); } // 导出数据 export(response, fileName, sheetName, sheetDataList, selectMap, dateFormat); } private static <T> List<ExcelClassField> getExcelClassFieldList(Class<T> clazz) { // 解析所有字段 Field[] fields = clazz.getDeclaredFields(); boolean hasExportAnnotation = false; Map<Integer, List<ExcelClassField>> map = new LinkedHashMap<>(); List<Integer> sortList = new ArrayList<>(); for (Field field : fields) { ExcelClassField cf = getExcelClassField(field); if (cf.getHasAnnotation() == 1) { hasExportAnnotation = true; } int sort = cf.getSort(); if (map.containsKey(sort)) { map.get(sort).add(cf); } else { List<ExcelClassField> list = new ArrayList<>(); list.add(cf); sortList.add(sort); map.put(sort, list); } } Collections.sort(sortList); // 获取表头 List<ExcelClassField> headFieldList = new ArrayList<>(); if (hasExportAnnotation) { for (Integer sort : sortList) { for (ExcelClassField cf : map.get(sort)) { if (cf.getHasAnnotation() == 1) { headFieldList.add(cf); } } } } else { headFieldList.addAll(map.get(0)); } return headFieldList; } private static ExcelClassField getExcelClassField(Field field) { ExcelClassField cf = new ExcelClassField(); String fieldName = field.getName(); cf.setFieldName(fieldName); ExcelExport annotation = field.getAnnotation(ExcelExport.class); // 无 ExcelExport 注解情况 if (annotation == null) { cf.setHasAnnotation(0); cf.setName(fieldName); cf.setSort(0); return cf; } // 有 ExcelExport 注解情况 cf.setHasAnnotation(1); cf.setName(annotation.value()); String example = getString(annotation.example()); if (!example.isEmpty()) { if (isNumeric(example)) { cf.setExample(Double.valueOf(example)); } else { cf.setExample(example); } } else { cf.setExample(""); } cf.setSort(annotation.sort()); // 解析映射 String kv = getString(annotation.kv()); cf.setKvMap(getKvMap(kv)); return cf; } private static LinkedHashMap<String, String> getKvMap(String kv) { LinkedHashMap<String, String> kvMap = new LinkedHashMap<>(); if (kv.isEmpty()) { return kvMap; } String[] kvs = kv.split(";"); if (kvs.length == 0) { return kvMap; } for (String each : kvs) { String[] eachKv = getString(each).split("-"); if (eachKv.length != 2) { continue; } String k = eachKv[0]; String v = eachKv[1]; if (k.isEmpty() || v.isEmpty()) { continue; } kvMap.put(k, v); } return kvMap; } /** * 导出表格到本地 * * @param file 本地文件对象 * @param sheetData 导出数据 */ public static void exportFile(File file, List<List<Object>> sheetData, String dateFormat) { if (file == null) { System.out.println("文件创建失败"); return; } if (sheetData == null) { sheetData = new ArrayList<>(); } Map<String, List<List<Object>>> map = new HashMap<>(); map.put(file.getName(), sheetData); export(null, file, file.getName(), map, null, dateFormat); } /** * 导出表格到本地 * * @param <T> 导出数据类似,和K类型保持一致 * @param filePath 文件父路径(如:D:/doc/excel/) * @param fileName 文件名称(不带尾缀,如:学生表) * @param list 导出数据 * @throws IOException IO异常 */ public static <T> File exportFile(String filePath, String fileName, List<T> list, String dateFormat) throws IOException { File file = getFile(filePath, fileName); List<List<Object>> sheetData = getSheetData(list); exportFile(file, sheetData, dateFormat); return file; } /** * 获取文件 * * @param filePath filePath 文件父路径(如:D:/doc/excel/) * @param fileName 文件名称(不带尾缀,如:用户表) * @return 本地File文件对象 */ private static File getFile(String filePath, String fileName) throws IOException { String dirPath = getString(filePath); String fileFullPath; if (dirPath.isEmpty()) { fileFullPath = fileName; } else { // 判定文件夹是否存在,如果不存在,则级联创建 File dirFile = new File(dirPath); if (!dirFile.exists()) { dirFile.mkdirs(); } // 获取文件夹全名 if (dirPath.endsWith(String.valueOf(LEAN_LINE))) { fileFullPath = dirPath + fileName + XLSX; } else { fileFullPath = dirPath + LEAN_LINE + fileName + XLSX; } } System.out.println(fileFullPath); File file = new File(fileFullPath); if (!file.exists()) { file.createNewFile(); } return file; } private static <T> List<List<Object>> getSheetData(List<T> list) { // 获取表头字段 List<ExcelClassField> excelClassFieldList = getExcelClassFieldList(list.get(0).getClass()); List<String> headFieldList = new ArrayList<>(); List<Object> headList = new ArrayList<>(); Map<String, ExcelClassField> headFieldMap = new HashMap<>(); for (ExcelClassField each : excelClassFieldList) { String fieldName = each.getFieldName(); headFieldList.add(fieldName); headFieldMap.put(fieldName, each); headList.add(each.getName()); } // 添加表头名称 List<List<Object>> sheetDataList = new ArrayList<>(); sheetDataList.add(headList); // 获取表数据 for (T t : list) { Map<String, Object> fieldDataMap = getFieldDataMap(t); Set<String> fieldDataKeys = fieldDataMap.keySet(); List<Object> rowList = new ArrayList<>(); for (String headField : headFieldList) { if (!fieldDataKeys.contains(headField)) { continue; } Object data = fieldDataMap.get(headField); if (data == null) { rowList.add(""); continue; } // 超防止过11位的数字自动转换为科学计数法 String string = data.toString(); if (isNumeric(string) && string.length() > 11) { data = new BigDecimal(string).toPlainString(); } ExcelClassField cf = headFieldMap.get(headField); // 判断是否有映射关系 LinkedHashMap<String, String> kvMap = cf.getKvMap(); if (kvMap == null || kvMap.isEmpty()) { rowList.add(data); continue; } String val = kvMap.get(data.toString()); if (val == null) { rowList.add(data); continue; } if (isNumeric(val)) { rowList.add(Double.valueOf(val)); } else { rowList.add(val); } } sheetDataList.add(rowList); } return sheetDataList; } private static <T> Map<String, Object> getFieldDataMap(T t) { Map<String, Object> map = new HashMap<>(); Field[] fields = t.getClass().getDeclaredFields(); try { for (Field field : fields) { String fieldName = field.getName(); field.setAccessible(true); Object object = field.get(t); map.put(fieldName, object); } } catch (IllegalArgumentException | IllegalAccessException e) { e.printStackTrace(); } return map; } public static void exportEmpty(HttpServletResponse response, String fileName, String dateFormat) { List<List<Object>> sheetDataList = new ArrayList<>(); List<Object> headList = new ArrayList<>(); headList.add("导出无数据"); sheetDataList.add(headList); export(response, fileName, sheetDataList, dateFormat); } public static void export(HttpServletResponse response, String fileName, List<List<Object>> sheetDataList, String dateFormat) { export(response, fileName, fileName, sheetDataList, null, dateFormat); } public static void exportManySheet(HttpServletResponse response, String fileName, Map<String, List<List<Object>>> sheetMap, String dateFormat) { export(response, null, fileName, sheetMap, null, dateFormat); } public static void export(HttpServletResponse response, String fileName, String sheetName, List<List<Object>> sheetDataList, String dateFormat) { export(response, fileName, sheetName, sheetDataList, null, dateFormat); } public static void export(HttpServletResponse response, String fileName, String sheetName, List<List<Object>> sheetDataList, Map<Integer, List<String>> selectMap, String dateFormat) { Map<String, List<List<Object>>> map = new HashMap<>(); map.put(sheetName, sheetDataList); export(response, null, fileName, map, selectMap, dateFormat); } public static <T, K> void export(HttpServletResponse response, String fileName, List<T> list, Class<K> template) { String dateFormat = DATE_FORMAT; // list 是否为空 boolean lisIsEmpty = list == null || list.isEmpty(); // 如果模板数据为空,且导入的数据为空,则导出空文件 if (template == null && lisIsEmpty) { exportEmpty(response, fileName, dateFormat); return; } // 如果 list 数据,则导出模板数据 if (lisIsEmpty) { exportTemplate(response, fileName, template, dateFormat); return; } // 导出数据 List<List<Object>> sheetDataList = getSheetData(list); export(response, fileName, sheetDataList, dateFormat); } public static <T, K> void export(HttpServletResponse response, String fileName, List<T> list, Class<K> template, String dateFormat) { // list 是否为空 boolean lisIsEmpty = list == null || list.isEmpty(); // 如果模板数据为空,且导入的数据为空,则导出空文件 if (template == null && lisIsEmpty) { exportEmpty(response, fileName, dateFormat); return; } // 如果 list 数据,则导出模板数据 if (lisIsEmpty) { exportTemplate(response, fileName, template, dateFormat); return; } // 导出数据 List<List<Object>> sheetDataList = getSheetData(list); export(response, fileName, sheetDataList, dateFormat); } public static void export(HttpServletResponse response, String fileName, List<List<Object>> sheetDataList, Map<Integer, List<String>> selectMap, String dateFormat) { export(response, fileName, fileName, sheetDataList, selectMap, dateFormat); } private static void export(HttpServletResponse response, File file, String fileName, Map<String, List<List<Object>>> sheetMap, Map<Integer, List<String>> selectMap, String dateFormat) { // 整个 Excel 表格 book 对象 SXSSFWorkbook book = new SXSSFWorkbook(); // 每个 Sheet 页 Set<Entry<String, List<List<Object>>>> entries = sheetMap.entrySet(); for (Entry<String, List<List<Object>>> entry : entries) { List<List<Object>> sheetDataList = entry.getValue(); Sheet sheet = book.createSheet(entry.getKey()); Drawing<?> patriarch = sheet.createDrawingPatriarch(); // 设置表头背景色(灰色) CellStyle headStyle = book.createCellStyle(); headStyle.setFillForegroundColor(IndexedColors.GREY_80_PERCENT.index); headStyle.setFillPattern(FillPatternType.SOLID_FOREGROUND); headStyle.setAlignment(HorizontalAlignment.CENTER); headStyle.setFillForegroundColor(IndexedColors.GREY_25_PERCENT.index); // 设置表身背景色(默认色) CellStyle rowStyle = book.createCellStyle(); rowStyle.setAlignment(HorizontalAlignment.CENTER); rowStyle.setVerticalAlignment(VerticalAlignment.CENTER); //创建一个DataFormat对象 DataFormat format = book.createDataFormat(); rowStyle.setDataFormat(format.getFormat("@")); // 设置表格列宽度(默认为15个字节) sheet.setDefaultColumnWidth(15); // 创建合并算法数组 int rowLength = sheetDataList.size(); int columnLength = sheetDataList.get(0).size(); int[][] mergeArray = new int[rowLength][columnLength]; for (int i = 0; i < sheetDataList.size(); i++) { // 每个 Sheet 页中的行数据 Row row = sheet.createRow(i); List<Object> rowList = sheetDataList.get(i); for (int j = 0; j < rowList.size(); j++) { // 每个行数据中的单元格数据 Object o = rowList.get(j); int v = 0; if (o instanceof URL) { // 如果要导出图片的话, 链接需要传递 URL 对象 setCellPicture(book, row, patriarch, i, j, (URL) o); } else { Cell cell = row.createCell(j); if (i == 0) { // 第一行为表头行,采用灰色底背景 v = setCellValue(cell, o, headStyle, dateFormat); } else { // 其他行为数据行,默认白底色 v = setCellValue(cell, o, rowStyle, dateFormat); } } mergeArray[i][j] = v; } } // 合并单元格 mergeCells(sheet, mergeArray); // 设置下拉列表 setSelect(sheet, selectMap); } // 写数据 if (response != null) { // 前端导出 try { write(response, book, fileName); } catch (IOException e) { e.printStackTrace(); } } else { // 本地导出 FileOutputStream fos; try { fos = new FileOutputStream(file); ByteArrayOutputStream ops = new ByteArrayOutputStream(); book.write(ops); fos.write(ops.toByteArray()); fos.close(); } catch (Exception e) { e.printStackTrace(); } } } /** * 合并当前Sheet页的单元格 * * @param sheet 当前 sheet 页 * @param mergeArray 合并单元格算法 */ private static void mergeCells(Sheet sheet, int[][] mergeArray) { // 横向合并 for (int x = 0; x < mergeArray.length; x++) { int[] arr = mergeArray[x]; boolean merge = false; int y1 = 0; int y2 = 0; for (int y = 0; y < arr.length; y++) { int value = arr[y]; if (value == CELL_COLUMN_MERGE) { if (!merge) { y1 = y; } y2 = y; merge = true; } else { merge = false; if (y1 > 0) { sheet.addMergedRegion(new CellRangeAddress(x, x, (y1 - 1), y2)); } y1 = 0; y2 = 0; } } if (y1 > 0) { sheet.addMergedRegion(new CellRangeAddress(x, x, (y1 - 1), y2)); } } // 纵向合并 int xLen = mergeArray.length; int yLen = mergeArray[0].length; for (int y = 0; y < yLen; y++) { boolean merge = false; int x1 = 0; int x2 = 0; for (int x = 0; x < xLen; x++) { int value = mergeArray[x][y]; if (value == CELL_ROW_MERGE) { if (!merge) { x1 = x; } x2 = x; merge = true; } else { merge = false; if (x1 > 0) { sheet.addMergedRegion(new CellRangeAddress((x1 - 1), x2, y, y)); } x1 = 0; x2 = 0; } } if (x1 > 0) { sheet.addMergedRegion(new CellRangeAddress((x1 - 1), x2, y, y)); } } } private static void write(HttpServletResponse response, SXSSFWorkbook book, String fileName) throws IOException { /*response.setContentType("application/vnd.openxmlformats-officedocument.spreadsheetml.sheet"); response.setCharacterEncoding("utf-8"); String name = new String(fileName.getBytes("GBK"), "ISO8859_1") + XLSX; response.addHeader("Content-Disposition", "attachment;filename=" + name);*/ /*String formFileName = new String(fileName.getBytes(StandardCharsets.UTF_8), StandardCharsets.ISO_8859_1); response.setHeader("Content-Disposition", String.format("attachment; filename=\"%s\";", formFileName)); response.setContentType("multipart/form-data"); response.setCharacterEncoding("UTF-8");*/ ServletRequestAttributes attributes = (ServletRequestAttributes) RequestContextHolder.getRequestAttributes(); assert attributes != null; HttpServletRequest request = attributes.getRequest(); response.setContentType("multipart/form-data;charset=UTF-8"); String userAgent = request.getHeader("USER-AGENT"); try { if (userAgent.contains("MSIE") || userAgent.contains("Edge")) {// IE浏览器 fileName = URLEncoder.encode(fileName, "UTF8"); } else if (userAgent.contains("Mozilla")) {// google,火狐浏览器 fileName = new String(fileName.getBytes(), "ISO8859-1"); } else { fileName = URLEncoder.encode(fileName, "UTF8");// 其他浏览器 } response.setHeader("Content-disposition", "attachment; filename=" + fileName); } catch (UnsupportedEncodingException e) { e.printStackTrace(); } ServletOutputStream out = response.getOutputStream(); book.write(out); out.flush(); out.close(); } private static int setCellValue(Cell cell, Object o, CellStyle style, String dateFormat) { // 设置样式 cell.setCellStyle(style); // 数据为空时 if (o == null) { cell.setCellType(CellType.STRING); cell.setCellValue(""); return CELL_OTHER; } // 是否为字符串 if (o instanceof String) { String s = o.toString(); if (isNumeric(s)) { if (s.length() > 11) { cell.setCellType(CellType.STRING); cell.setCellValue(s); return CELL_OTHER; } else { cell.setCellType(CellType.NUMERIC); cell.setCellValue(Double.parseDouble(s)); return CELL_OTHER; } } else { cell.setCellType(CellType.STRING); cell.setCellValue(s); } if (s.equals(ROW_MERGE)) { return CELL_ROW_MERGE; } else if (s.equals(COLUMN_MERGE)) { return CELL_COLUMN_MERGE; } else { return CELL_OTHER; } } // 是否为字符串 if (o instanceof Integer || o instanceof Long || o instanceof Double || o instanceof Float) { cell.setCellType(CellType.NUMERIC); cell.setCellValue(Double.parseDouble(o.toString())); return CELL_OTHER; } // 是否为Boolean if (o instanceof Boolean) { cell.setCellType(CellType.BOOLEAN); cell.setCellValue((Boolean) o); return CELL_OTHER; } // 如果是BigDecimal,则默认3位小数 if (o instanceof BigDecimal) { cell.setCellType(CellType.NUMERIC); cell.setCellValue(((BigDecimal) o).setScale(3, RoundingMode.HALF_UP).doubleValue()); return CELL_OTHER; } // 如果是Date数据,则显示格式化数据 if (o instanceof Date) { cell.setCellType(CellType.STRING); cell.setCellValue(formatDate((Date) o, dateFormat)); return CELL_OTHER; } // 如果是其他,则默认字符串类型 cell.setCellType(CellType.STRING); cell.setCellValue(o.toString()); return CELL_OTHER; } private static void setCellPicture(SXSSFWorkbook wb, Row sr, Drawing<?> patriarch, int x, int y, URL url) { // 设置图片宽高 sr.setHeight((short) (IMG_WIDTH * IMG_HEIGHT)); // (jdk1.7版本try中定义流可自动关闭) try (InputStream is = url.openStream(); ByteArrayOutputStream outputStream = new ByteArrayOutputStream()) { byte[] buff = new byte[BYTES_DEFAULT_LENGTH]; int rc; while ((rc = is.read(buff, 0, BYTES_DEFAULT_LENGTH)) > 0) { outputStream.write(buff, 0, rc); } // 设置图片位置 XSSFClientAnchor anchor = new XSSFClientAnchor(0, 0, 0, 0, y, x, y + 1, x + 1); // 设置这个,图片会自动填满单元格的长宽 anchor.setAnchorType(AnchorType.MOVE_AND_RESIZE); patriarch.createPicture(anchor, wb.addPicture(outputStream.toByteArray(), HSSFWorkbook.PICTURE_TYPE_JPEG)); } catch (Exception e) { e.printStackTrace(); } } private static String formatDate(Date date, String dateFormat) { if (date == null) { return ""; } if (dateFormat == null) { dateFormat = DATE_FORMAT; } SimpleDateFormat format = new SimpleDateFormat(dateFormat); return format.format(date); } private static void setSelect(Sheet sheet, Map<Integer, List<String>> selectMap) { if (selectMap == null || selectMap.isEmpty()) { return; } Set<Entry<Integer, List<String>>> entrySet = selectMap.entrySet(); for (Entry<Integer, List<String>> entry : entrySet) { int y = entry.getKey(); List<String> list = entry.getValue(); if (list == null || list.isEmpty()) { continue; } String[] arr = new String[list.size()]; for (int i = 0; i < list.size(); i++) { arr[i] = list.get(i); } DataValidationHelper helper = sheet.getDataValidationHelper(); CellRangeAddressList addressList = new CellRangeAddressList(1, 65000, y, y); DataValidationConstraint dvc = helper.createExplicitListConstraint(arr); DataValidation dv = helper.createValidation(dvc, addressList); if (dv instanceof HSSFDataValidation) { dv.setSuppressDropDownArrow(false); } else { dv.setSuppressDropDownArrow(true); dv.setShowErrorBox(true); } sheet.addValidationData(dv); } } private static boolean isNumeric(String str) { if ("0.0".equals(str)) { return true; } if ("".equals(str)) { return false; } for (int i = str.length(); --i >= 0; ) { if (!Character.isDigit(str.charAt(i))) { return false; } } return true; } private static String getString(String s) { if (s == null) { return ""; } if (s.isEmpty()) { return s; } return s.trim(); } } 三、相关业务代码 1.service层 /*** 车运运单信息导出*/ List<ExportBillVo> exportBillInfo(List<Long> billIdList); 2.impl实现类

 实现类里的代码,需求各位根据自己的业务场景进行改动,将需要导出的数据查询出来

  @Override public List<ExportBillVo> exportBillInfo(List<Long> billIdList) { if (StringUtils.isEmpty(billIdList)) { throw new ServiceException("车辆运单ID不能为空"); } BillDto billDto = new BillDto(); billDto.setBillIdList(billIdList); List<BillDto> billList = billFacadeService.queryBillList(billDto); if (StringUtils.isEmpty(billList)) { billList = new ArrayList<>(); } return InvoiceWrapper.instance.convertTo(billList); } 3.controller层

 controller层的代码需要注意的是:

1.因为导出Excel一般都是通过浏览器进行下载的,所以入参中需要加入HttpServletResponse

2.调用封装的工具类ExcelUtils中的export方法就可以了

  /** * 车运运单信息导出 */ @Log @PostMapping("/exportBillInfo") public void exportBillInfo(@RequestBody @Valid BillListDto dto, HttpServletResponse response) { List<ExportBillVo> list = invoiceFacadeService.exportBillInfo(dto.getBillIdList()); ExcelUtils.export(response, "车运运单信息", list, ExportBillVo.class); }

最终导出的Excel文件:

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