meethigher-Apache Poi 实现Excel多级联动下拉框-编程知识

由于最近做的功能，需要将接口返回的数据列表，输出到excel中，以供后续导入，且网上现有的封装，使用起来都较为麻烦，故参考已有做法封装了工具类。

使用apache poi实现excel联动下拉框思路

创建隐藏单元格，存储下拉数据
创建名称管理器
使用indirect表达式进行联动

添加依赖

<!--Java程序对Microsoft Office格式档案读和写的功能-->
<dependency><groupId>org.apache.poi</groupId><artifactId>poi</artifactId><version>5.2.2</version>
</dependency>
<dependency><groupId>org.apache.poi</groupId><artifactId>poi-ooxml</artifactId><version>5.2.2</version>
</dependency>

直接上代码

import org.apache.poi.ss.usermodel.*;
import org.apache.poi.ss.util.CellRangeAddressList;
import org.apache.poi.xssf.usermodel.*;import java.util.List;
import java.util.Map;
import java.util.Set;/*** excel验证工具类** @author chenchuancheng github.com/meethigher* @since 2023/08/20 23:55*/
public class ExcelValidationUtils {private static final int minRow = 1;private static final int maxRow = 100;private static final boolean debugHideSheet = true;/*** 创建一个xlsx** @return {@link XSSFWorkbook}*/public static XSSFWorkbook createOneXLSX() {return new XSSFWorkbook();}/*** 为xlsx添加一个sheet** @param wb        xlsx* @param sheetName sheet名* @param headers   首行标题头* @return sheet*/public static XSSFSheet addOneSheet(XSSFWorkbook wb, String sheetName, String[] headers) {XSSFSheet st = wb.createSheet(sheetName);//表头样式CellStyle style = wb.createCellStyle();style.setAlignment(HorizontalAlignment.CENTER); // 创建一个居中格式//字体样式Font fontStyle = wb.createFont();fontStyle.setFontName("微软雅黑");fontStyle.setFontHeightInPoints((short) 12);style.setFont(fontStyle);//单元格格式为文本XSSFDataFormat format = wb.createDataFormat();style.setDataFormat(format.getFormat("@"));//写标题XSSFRow row = st.createRow(0);st.createFreezePane(0, 1, 0, 1);for (int i = 0; i < headers.length; i++) {String value = headers[i];XSSFCell cell = row.createCell(i);st.setColumnWidth(i, value.length() * 1000);cell.setCellStyle(style);st.setDefaultColumnStyle(i, style);cell.setCellValue(value);}return st;}/*** 添加两层级联数据** @param wb                  xlsx* @param targetSheet         目标sheet* @param linkageData         两层级联数据* @param parentCol           父列* @param childCol            孩子列* @param parentColIdentifier 父列标识符* @return {@link XSSFSheet}*/public static XSSFSheet addLinkageDataValidation(XSSFWorkbook wb, XSSFSheet targetSheet, Map<String, List<String>> linkageData,int parentCol, int childCol, String parentColIdentifier) {XSSFSheet hideSt = wb.createSheet();wb.setSheetHidden(wb.getSheetIndex(hideSt), !debugHideSheet);int rowId = 0;Set<String> keySet = linkageData.keySet();for (String parent : keySet) {List<String> sonList = linkageData.get(parent);XSSFRow row = hideSt.createRow(rowId++);row.createCell(0).setCellValue(parent);for (int i = 0; i < sonList.size(); i++) {XSSFCell cell = row.createCell(i + 1);cell.setCellValue(sonList.get(i));}// 添加名称管理器,1表示b列,从b列开始往后，都是子级String range = getRange(1, rowId, sonList.size());Name name = wb.createName();name.setNameName(parent);String formula = hideSt.getSheetName() + "!" + range;name.setRefersToFormula(formula);}//创建表达式校验XSSFDataValidationHelper helper = new XSSFDataValidationHelper(targetSheet);//        //父级校验，如需生成更多，用户手动拖拽下拉即可。此操作会导致数组内容总长度超过255时报错
//        DataValidation parentValidation = helper.createValidation(helper.createExplicitListConstraint(keySet.toArray(new String[0])),
//                new CellRangeAddressList(minRow, maxRow, parentCol, parentCol));
//        parentValidation.createErrorBox("错误", "请选择正确的父级类型");
//        parentValidation.setShowErrorBox(true);
//        parentValidation.setSuppressDropDownArrow(true);
//        targetSheet.addValidationData(parentValidation);//解决长度为255的问题Name name = wb.createName();name.setNameName(hideSt.getSheetName());name.setRefersToFormula(hideSt.getSheetName() + "!$A$1:$A$" + keySet.size());DataValidation parentValidation = helper.createValidation(helper.createFormulaListConstraint(hideSt.getSheetName()), new CellRangeAddressList(minRow, maxRow, parentCol, parentCol));parentValidation.createErrorBox("错误", "请选择正确的父级类型");parentValidation.setShowErrorBox(true);targetSheet.addValidationData(parentValidation);//子级校验，如需生成更多，用户手动拖拽下拉即可for (int i = minRow; i < maxRow; i++) {DataValidation childValidation = helper.createValidation(helper.createFormulaListConstraint("INDIRECT(" + parentColIdentifier + "" + (i + 1) + ")"),new CellRangeAddressList(i, i, childCol, childCol));childValidation.createErrorBox("错误", "请选择正确的子级类型");childValidation.setShowErrorBox(true);childValidation.setSuppressDropDownArrow(true);targetSheet.addValidationData(childValidation);}return hideSt;}/*** 添加简单下拉列表验证-下拉列表总内容不超过255字符** @param st           sheet* @param dropDownList 下拉列表数据* @param firstCol     开始列，从0开始* @param lastCol      结束列，从0开始*/public static void addSimpleDropDownListValidation(XSSFSheet st, String[] dropDownList, int firstCol, int lastCol) {XSSFDataValidationHelper helper = new XSSFDataValidationHelper(st);XSSFDataValidationConstraint constraint = (XSSFDataValidationConstraint) helper.createExplicitListConstraint(dropDownList);CellRangeAddressList addressList = new CellRangeAddressList(minRow, maxRow, firstCol, lastCol);XSSFDataValidation validation = (XSSFDataValidation) helper.createValidation(constraint, addressList);validation.setSuppressDropDownArrow(true);validation.setShowErrorBox(true);st.addValidationData(validation);}/*** 添加复杂下拉列表验证-下拉列表总内容允许超过255字符** @param wb           xlsx* @param dropDownList 下拉列表数据* @param firstCol     开始列，从0开始* @param lastCol      结束列，从0开始*/public static void addComplexDropDownListValidation(XSSFWorkbook wb, XSSFSheet st, String[] dropDownList, int firstCol, int lastCol) {XSSFSheet hideSt = wb.createSheet();wb.setSheetHidden(wb.getSheetIndex(hideSt), !debugHideSheet);XSSFDataValidationHelper helper = new XSSFDataValidationHelper(st);for (int i = 0, length = dropDownList.length; i < length; i++) {String value = dropDownList[i];XSSFRow row = hideSt.createRow(i);XSSFCell cell = row.createCell(0);cell.setCellValue(value);}//解决长度为255的问题Name name = wb.createName();name.setNameName(hideSt.getSheetName());name.setRefersToFormula(hideSt.getSheetName() + "!$A$1:$A$" + dropDownList.length);DataValidation parentValidation = helper.createValidation(helper.createFormulaListConstraint(hideSt.getSheetName()), new CellRangeAddressList(minRow, maxRow, firstCol, lastCol));parentValidation.createErrorBox("错误", "请选择正确的类型");parentValidation.setShowErrorBox(true);st.addValidationData(parentValidation);}/*** 计算formula** @param offset   偏移量，如果给0，表示从A列开始，1，就是从B列* @param rowId    第几行* @param colCount 一共多少列* @return 如果给入参 1,1,10. 表示从B1-K1。最终返回 $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 + "$" + rowId;} else {char endPrefix = 'A', endSuffix;if ((colCount - 25) / 26 == 0 || colCount == 51) {// 26-51之间，包括边界（仅两次字母表计算）if ((colCount - 25) % 26 == 0) {// 边界值endSuffix = (char) ('A' + 25);} else {endSuffix = (char) ('A' + (colCount - 25) % 26 - 1);}} else {// 51以上if ((colCount - 25) % 26 == 0) {endSuffix = (char) ('A' + 25);endPrefix = (char) (endPrefix + (colCount - 25) / 26 - 1);} else {endSuffix = (char) ('A' + (colCount - 25) % 26 - 1);endPrefix = (char) (endPrefix + (colCount - 25) / 26);}}return "$" + start + "$" + rowId + ":$" + endPrefix + endSuffix + "$" + rowId;}}
}

使用示例

public class TestExportExcelWithValidation {private final static String[] headers = new String[]{"性别","省","市","区",};private static Map<String, List<String>> 省级() {Map<String, List<String>> map = new HashMap<>();map.put("湖北省", Arrays.asList("武汉市", "襄阳市"));map.put("吉林省", Arrays.asList("长春市", "吉林市"));return map;}private static Map<String, List<String>> 市级() {Map<String, List<String>> map = new HashMap<>();map.put("武汉市", Arrays.asList("洪山区", "江夏区"));map.put("长春市", Arrays.asList("宽城区", "南关区"));return map;}public static void main(String[] args) throws Exception {XSSFWorkbook wb = createOneXLSX();XSSFSheet st = addOneSheet(wb, "data", headers);addSimpleDropDownListValidation(st, new String[]{"男", "女"}, 0, 0);addLinkageDataValidation(wb, st, 省级(), 1, 2, "B");addLinkageDataValidation(wb, st, 市级(), 2, 3, "C");wb.write(new FileOutputStream("aaa.xlsx"));}
}