Java Web匯出excel表，瀏覽器下載匯出excel表
阿新 • • 發佈：2018-12-20
1 自定義註解
@Target(ElementType.FIELD)
@Retention(RetentionPolicy.RUNTIME)
public @interface ExcelTable {
String value() default "";
}2 使用在欄位上
/** * 使用舉例 */ public class User { //姓名 @ExcelTable("姓名") private String name; //性別 @ExcelTable("性別") private String sex; //年齡 @ExcelTable("年齡") private String age; }
3 匯出excel表的工具類
/** * Excel匯出工具類 * * @author ellen * @version 1.0 * @date 2018/11/11 */ public class ExcelUtil { /** * @param list * @param sheetName * @param response * @param <T> * @throws Exception * @Description : 匯出Excel（匯出到瀏覽器，工作表的大小是2003支援的最大值） */ public static <T> void listToExcel(List<T> list, String sheetName, HttpServletResponse response) throws Exception { listToExcel(list, sheetName, 65535, response); } /** * @param list * @param sheetName * @param response * @param <T> * @throws Exception * @Description : 匯出Excel（匯出到瀏覽器，可以自定義工作表的大小） */ public static <T> void listToExcel(List<T> list, String sheetName, int sheetSize, HttpServletResponse response) throws Exception { //設定預設檔名為當前時間：年月日時分秒 String fileName = new SimpleDateFormat("yyyyMMddhhmmss").format(new Date()).toString(); //設定response頭資訊 response.reset(); //改成輸出excel檔案 response.setContentType("application/vnd.ms-excel"); //設定檔案下載頭 response.setHeader("Content-disposition", "attachment; filename=" + fileName + ".xls"); try { OutputStream out = response.getOutputStream(); listToExcel(list, sheetSize, sheetName, out); } catch (Exception e) { e.printStackTrace(); //如果是ExcelException，則直接丟擲 if (e instanceof CustomException) { throw (CustomException) e; //否則將其它異常包裝成ExcelException再丟擲 } else { throw new CustomException("匯出Excel失敗"); } } } /** * 一次匯出全部 * * @param list * @param sheetSize 每個工作表記錄的最大數值 * @param sheetName 每個工作表的名字 * @param out 匯出流 * @param <T> * @throws Exception * @Description : 匯出Excel（可以匯出到本地檔案系統,可自定義工作表大小） */ public static <T> void listToExcel(List<T> list, int sheetSize, String sheetName, OutputStream out) throws Exception { if (list.size() == 0 || list == null) { throw new CustomException("資料來源中沒有任何資料"); } //最大數值為65535 if (sheetSize > 65535 || sheetSize < 1) { sheetSize = 65535; } //新建一個xls工作簿 Workbook wb = new HSSFWorkbook(); CreationHelper createHelper = wb.getCreationHelper(); Sheet sheet = null; //如果數值太多，放到多個工作表中 //計算一共有多少個工作表 double sheetNum = Math.ceil(list.size() / new Integer(sheetSize).doubleValue()); //多個工作表的情況 for (int i = 0; i < sheetNum; i++) { if (sheetNum == 1) { //新建一個表 sheet = wb.createSheet(sheetName);//表的名字是Excel不得超過31個字元 fillSheet(list, sheet, 0, list.size() - 1); } else { //獲取開始索引和結束索引 int firstIndex = i * sheetSize; int lastIndex = (i + 1) * sheetSize - 1 > list.size() - 1 ? list.size() - 1 : (i + 1) * sheetSize - 1; sheet = wb.createSheet(sheetName + (i + 1)); fillSheet(list, sheet, firstIndex, lastIndex); } } // Write the output to a file wb.write(out); } /** * 填充資料 * * @param list * @param sheet 工作表插入 * @param firstIndex 開始索引 * @param lastIndex 結束索引 * @param <T> * @throws Exception */ private static <T> void fillSheet(List<T> list, Sheet sheet, int firstIndex, int lastIndex) throws Exception { Field[] fields = list.get(0).getClass().getDeclaredFields(); //記錄行數 int rowNum = 0; //記錄列數 int cellNum = 0; Row row = sheet.createRow(0); row.setHeightInPoints(30); rowNum++; List<String> keylist = new ArrayList<>(); for (Field field : fields) { Cell cell = row.createCell(cellNum); if (field.isAnnotationPresent(ExcelTable.class)) { ExcelTable excelRowName = field.getAnnotation(ExcelTable.class); cell.setCellValue(excelRowName.value()); //儲存到list keylist.add(field.getName()); cellNum++; } } for (int index = firstIndex; index <= lastIndex; index++) { T object = list.get(index); Row row1 = sheet.createRow(rowNum); rowNum++; cellNum = 0; for (String string : keylist) { Field field = object.getClass().getDeclaredField(string); //設為可見 field.setAccessible(true); Object value = field.get(object); Cell cell = row1.createCell(cellNum); //不需要做處理 if (value != null) { cell.setCellValue(value.toString()); } cellNum++; } } } /** * 分工作表匯出 * * @param list * @param sheetSize 每個工作表的行數（不得超過65535） * @param sheetName 工作表的名稱 * @param <T> * @return * @throws Exception */ public static <T> Workbook CreateExcelWorkbook(List<T> list, int sheetSize, String sheetName) throws Exception { if (list.size() == 0 || list == null) { throw new CustomException("資料來源中沒有任何資料"); } //最大數值為65535 if (sheetSize > 65535 || sheetSize < 1) { throw new CustomException("sheetSize數值有誤"); } //新建一個xls工作簿 Workbook wb = new HSSFWorkbook(); CreationHelper createHelper = wb.getCreationHelper(); Sheet sheet = null; //新建一個表 sheet = wb.createSheet(sheetName);//表的名字是Excel不得超過31個字元 fillSheet(list, sheet, 0, list.size() - 1); return wb; } /** * 新增資料 * * @param list * @param sheetSize * @param sheetName * @param FilePath * @param <T> * @throws Exception */ public static <T> void addListToExcel(List<T> list, int sheetSize, String sheetName, String FilePath) throws Exception { if (list.size() == 0 || list == null) { throw new CustomException("資料來源中沒有任何資料"); } // 判斷資料大小是否比最後一個表剩餘的大小小，小的話可以直接在表中繼續寫，大的話在當前表中寫完後繼續在後面表中寫 //獲得一個xls工作簿 Workbook wb = returnWorkBookByFileName(FilePath); CreationHelper createHelper = wb.getCreationHelper(); //獲得最後一個工作表 Sheet sheet = wb.getSheetAt(wb.getNumberOfSheets() - 1); //記錄行數 int rowNum = sheet.getLastRowNum(); double sheetNum = 0; if (sheetSize > (65535 - sheet.getLastRowNum())) { // 判斷當前表填滿後還需要多少個表 sheetNum = Math.ceil((list.size() - (65535 - sheet.getLastRowNum())) / new Integer(65535).doubleValue()); } // 如果在當前表中可以能容納list大小的資料 if (sheetNum == 0) { ContinueToSheet(list, sheet, rowNum, 0, list.size() - 1); } else { int i = 0; // 將當前表填充完整 ContinueToSheet(list, sheet, rowNum, 0, 65535 - sheet.getLastRowNum()); i = 65535 - sheet.getLastRowNum(); // 繼續將新建表填充 for (int index = 0; index < sheetNum; index++) { sheet = wb.createSheet(sheetName + (i + 1)); ContinueToSheet(list, sheet, rowNum, i + 1, i + 65535); i += 65535; } } // Write the output to a file FileOutputStream fileOut = new FileOutputStream(FilePath); wb.write(fileOut); fileOut.close(); } /** * @param list * @param sheet 工作表插入 * @param beginIndex 開始索引 * @param endIndex 結束索引 * @param <T> * @throws Exception */ private static <T> void ContinueToSheet(List<T> list, Sheet sheet, int rowNum, int beginIndex, int endIndex) throws Exception { Field[] fields = list.get(0).getClass().getDeclaredFields(); // 獲得最後一行 Row row = sheet.getRow(rowNum); //記錄列數 int cellNum = 0; // 列數 List<String> keylist = null; // row.setHeightInPoints(30); keylist = new ArrayList<>(); for (Field field : fields) { if (field.isAnnotationPresent(ExcelTable.class)) { ExcelTable excelRowName = field.getAnnotation(ExcelTable.class); //儲存到list keylist.add(field.getName()); cellNum++; } } for (int index = beginIndex; index <= endIndex; index++) { T object = list.get(index); Row row1 = sheet.createRow(rowNum); rowNum++; cellNum = 0; for (String string : keylist) { Field field = object.getClass().getDeclaredField(string); //設為可見 field.setAccessible(true); Object value = field.get(object); Cell cell = row1.createCell(cellNum); if (value == null) { cell.setCellValue(" "); } else { //不需要做處理 if (value != null) { cell.setCellValue(value.toString()); } } cellNum++; } } } /** * 通過檔案輸入流得到一個工作蒲 * * @param is * @return * @throws IOException */ private static HSSFWorkbook returnWorkBookByFileStream(InputStream is) throws IOException { HSSFWorkbook wb = null; wb = new HSSFWorkbook(is); return wb; } /** * 通過檔案路徑得到一個工作蒲 * * @param FilePath * @return * @throws IOException */ private static HSSFWorkbook returnWorkBookByFileName(String FilePath) throws IOException { InputStream inp = new FileInputStream(FilePath); return returnWorkBookByFileStream(inp); } /** * @param list * @param sheetName * @param <T> * @throws Exception * @Description : 匯出Excel（可以匯出到本地檔案系統,工作表大小為2003支援的最大值） */ public static <T> void listToExcel(List<T> list, String sheetName, OutputStream outputStream) throws Exception { listToExcel(list, 65535, sheetName, outputStream); } /** * @param list * @param sheetSize * @param sheetName * @param FilePath * @param <T> * @throws Exception */ public static <T> void addListToExcel(List<T> list, int sheetSize, String sheetName, String FilePath, OutputStream out) throws Exception { if (list.size() == 0 || list == null) { throw new CustomException("資料來源中沒有任何資料"); } //最大數值為65535 if (sheetSize > 65535 || sheetSize < 1) { sheetSize = 65535; } //獲得一個xls工作簿 Workbook wb = returnWorkBookByFileName(FilePath); CreationHelper createHelper = wb.getCreationHelper(); //獲得最後一個工作表 Sheet sheet = wb.getSheetAt(wb.getNumberOfSheets() - 1); //判斷當前新增的表 if (sheetSize > (65535 - sheet.getLastRowNum())) { } double sheetNum = Math.ceil((list.size() + sheet.getLastRowNum()) / new Integer(sheetSize).doubleValue()); //多個工作表的情況 for (int i = 0; i < sheetNum; i++) { if (sheetNum == 1) { //新建一個表 // sheet = wb.createSheet(sheetName);//表的名字是Excel不得超過31個字元 addSheet(list, sheet, 0, list.size() - 1); } else { //獲取開始索引和結束索引 int firstIndex = i * sheetSize; int lastIndex = (i + 1) * sheetSize - 1 > list.size() - 1 ? list.size() - 1 : (i + 1) * sheetSize - 1; sheet = wb.createSheet(sheetName + (i + 1)); fillSheet(list, sheet, firstIndex, lastIndex); } } // Write the output to a file FileOutputStream fileOut = new FileOutputStream(FilePath); wb.write(fileOut); fileOut.close(); } /** * @param list * @param sheet 工作表插入 * @param firstIndex 開始索引 * @param lastIndex 結束索引 * @param <T> * @throws Exception */ private static <T> void addSheet(List<T> list, Sheet sheet, int firstIndex, int lastIndex) throws Exception { Field[] fields = list.get(0).getClass().getDeclaredFields(); //記錄行數 int rowNum = sheet.getLastRowNum(); //獲得最後一行 Row row = sheet.getRow(rowNum); //記錄列數 int cellNum = 0; // row.setHeightInPoints(30); rowNum++; List<String> keylist = new ArrayList<>(); for (Field field : fields) { Cell cell = row.createCell(cellNum); if (field.isAnnotationPresent(ExcelTable.class)) { ExcelTable excelRowName = field.getAnnotation(ExcelTable.class); cell.setCellValue(excelRowName.value()); //儲存到list keylist.add(field.getName()); cellNum++; } } for (int index = firstIndex; index <= lastIndex; index++) { T object = list.get(index); Row row1 = sheet.createRow(rowNum); rowNum++; cellNum = 0; for (String string : keylist) { Field field = object.getClass().getDeclaredField(string); //設為可見 field.setAccessible(true); Object value = field.get(object); Cell cell = row1.createCell(cellNum); if (value == null) { cell.setCellValue(" "); } else { cell.setCellValue(value.toString()); } cellNum++; } } } public static Workbook addDate(List<T> list, int sheetSize, String sheetName, Workbook wb) { if (list.size() == 0 || list == null) { throw new CustomException("資料來源中沒有任何資料"); } //最大數值為65535 if (sheetSize > 65535 || sheetSize < 1) { sheetSize = 65535; } CreationHelper createHelper = wb.getCreationHelper(); //獲得最後一個工作表 Sheet sheet = wb.getSheetAt(wb.getNumberOfSheets() - 1); //如果數值太多，放到多個工作表中 //計算一共有多少個工作表 double sheetNum = Math.ceil(list.size() + sheet.getLastRowNum() / new Integer(sheetSize).doubleValue()); //多個工作表的情況 for (int i = 0; i < sheetNum; i++) { // if(sheetNum == 1){ // //新建一個表 // // sheet = wb.createSheet(sheetName);//表的名字是Excel不得超過31個字元 // addSheet(list,sheet,0,list.size()-1); // } // else { // //獲取開始索引和結束索引 // int firstIndex=i * sheetSize; // int lastIndex=(i+1)*sheetSize-1>list.size()-1 ? list.size()-1 : (i+1)*sheetSize-1; // // sheet = wb.createSheet(sheetName + (i+1)); // fillSheet(list,sheet,firstIndex,lastIndex); // } // // // } // // // Write the output to a file // FileOutputStream fileOut = new FileOutputStream(FilePath); // wb.write(fileOut); // fileOut.close(); } return wb; } }