給自己打個廣告,最近弄了個Excel的工具,支持下拉框,級聯下拉框,隱藏Sheet,多線程大數據量導出,生產者消費者模式讀取,代碼大部分都有註釋,有興趣的朋友可以看看,覺得不錯可以幫我弄個star什麼的😄
實現方式
使用的excel的名稱管理器(類似Map)存儲級聯數據的關係,創建隱藏Sheet存儲級聯的數據,再創建名稱管理器,最後設置數據的關聯
代碼
會涉及到創建下拉框方法(createDropDownListWithHiddenSheet
),可以查看Java Excel POI 添加下拉框
/**
* 添加級聯下拉數據
*
* @param workbook workBook
* @param displaySheet 用於展示的Sheet
* @param sheetName 保存級聯數據的Sheet名稱
* @param parents 最頂層的父節點數組
* @param cascadeData key:父節點名稱 value:父節點對應的下一層子節點
* @param columnRelationships key:父下拉框列在Sheet的下標(頂級爲 -1) value:子下拉框列在sheet的下標
* @param maxRowNum 需要關聯下拉框數據的行數
*/
public static void createCascadeDropdownListTemp(Workbook workbook, Sheet displaySheet,
String sheetName, String[] parents,
Map<String, List<String>> cascadeData,
Map<Integer, Integer> columnRelationships, int maxRowNum) {
// 創建隱藏Sheet
Sheet hiddenSheet = workbook.createSheet(sheetName);
// 設置Sheet 隱藏
workbook.setSheetHidden(workbook.getSheetIndex(hiddenSheet), true);
int rowId = 0;
// 設置第一行,存頂級父節點的信息
Row firstRow = hiddenSheet.createRow(rowId++);
firstRow.createCell(0).setCellValue("父節點");
for (int i = 0; i < parents.length; i++) {
Cell firstRowCell = firstRow.createCell(i + 1);
firstRowCell.setCellValue(parents[i]);
}
// 創建所有父節點的數組
Set<String> parentSet = cascadeData.keySet();
String[] allParents = new String[parentSet.size()];
parentSet.toArray(allParents);
// 將具體的數據寫入到每一行中,行開頭爲父級區域,後面是子區域。
for (int i = 0; i < allParents.length; i++) {
String key = allParents[i];
List<String> son = cascadeData.get(key);
Row row = hiddenSheet.createRow(rowId++);
row.createCell(0).setCellValue(key);
for (int j = 0; j < son.size(); j++) {
Cell cell = row.createCell(j + 1);
cell.setCellValue(son.get(j));
}
// 添加名稱管理器
String range = getRange(1, rowId, son.size());
Name name = workbook.createName();
//key不可重複
name.setNameName(key);
String formula = sheetName + "!" + range;
name.setRefersToFormula(formula);
}
int firstParentIndex = columnRelationships.get(-1);
// 創建頂級父節點的下拉框(隱藏Sheet的方式)
createDropDownListWithHiddenSheet(displaySheet, 1, firstParentIndex, maxRowNum, firstParentIndex, parents, workbook, "hiddenParent" + sheetName);
for (Map.Entry<Integer, Integer> entry : columnRelationships.entrySet()) {
// 跳過頂級節點
if (entry.getKey() == -1) {
continue;
}
int index = entry.getValue();
int parentIndex = entry.getKey();
String parentOffset = String.valueOf((char) ((int) 'A' + parentIndex));
// poi的index從0開始
setDataValidation(parentOffset, displaySheet, 1, maxRowNum, index);
}
}
/**
* 設置有效性
*
* @param offset 主影響單元格所在列,即此單元格由哪個單元格影響聯動
* @param sheet
* @param rowNum 行數
* @param colNum 列數
*/
private static void setDataValidation(String offset, Sheet sheet, int rowNum, int lastRow, int colNum) {
CellRangeAddressList rangeAddressList = new CellRangeAddressList(rowNum, lastRow, colNum, colNum);
DataValidation cacse = null;
if (sheet instanceof XSSFSheet || sheet instanceof SXSSFSheet) {
DataValidationHelper dvHelper = sheet.getDataValidationHelper();
String formulaStringXlsx = "INDIRECT($" + offset + (rowNum + 1) + ")";
DataValidationConstraint dvConstraint = dvHelper.createFormulaListConstraint(formulaStringXlsx);
cacse = dvHelper.createValidation(dvConstraint, rangeAddressList);
} else {
String formulaString = "INDIRECT($" + offset + (rowNum) + ")";
DVConstraint formula = DVConstraint.createFormulaListConstraint(formulaString);
cacse = new HSSFDataValidation(rangeAddressList, formula);
}
cacse.createErrorBox("error", "請選擇正確的選項");
sheet.addValidationData(cacse);
}
/**
* 計算formula
*
* @param offset 偏移量,如果給0,表示從A列開始,1,就是從B列
* @param rowId 第幾行
* @param colCount 一共多少列
* @return 如果給入參 1,1,10. 表示從B1-K1。最終返回 $B$1:$K$1
*/
private static String getRange(int offset, int rowId, int colCount) {
char start = (char) ('A' + offset);
if (colCount <= 25) {
char end = (char) (start + colCount - 1);
return "$" + start + "$" + rowId + ":$" + end + "$" + rowId;
} else {
char endPrefix = 'A';
char endSuffix = 'A';
if ((colCount - 25) / 26 == 0 || colCount == 51) {// 26-51之間,包括邊界(僅兩次字母表計算)
if ((colCount - 25) % 26 == 0) {// 邊界值
endSuffix = (char) ('A' + 25);
} else {
endSuffix = (char) ('A' + (colCount - 25) % 26 - 1);
}
} else {// 51以上
if ((colCount - 25) % 26 == 0) {
endSuffix = (char) ('A' + 25);
endPrefix = (char) (endPrefix + (colCount - 25) / 26 - 1);
} else {
endSuffix = (char) ('A' + (colCount - 25) % 26 - 1);
endPrefix = (char) (endPrefix + (colCount - 25) / 26);
}
}
return "$" + start + "$" + rowId + ":$" + endPrefix + endSuffix + "$" + rowId;
}
}
注意
經過踩坑,由於名稱管理器中是不支持各種特殊符號的(以及純數字),比如逗號和分號都不行,有這方面的需求的請謹慎使用