java poi excel 下拉框多选的实现方法是什么？

您可以使用 DataValidation 类来实现 Java POI Excel 下拉框多选。以下是一个示例代码：

// 创建下拉列表选项
String[] options = {"选项1", "选项2", "选项3"};
DataValidationHelper validationHelper = new XSSFDataValidationHelper(sheet);
CellRangeAddressList addressList = new CellRangeAddressList(0, 0, 0, 0);
DataValidationConstraint constraint = validationHelper.createExplicitListConstraint(options);
DataValidation dataValidation = validationHelper.createValidation(constraint, addressList);

// 设置下拉列表多选
dataValidation.setShowErrorBox(true);
dataValidation.setSuppressDropDownArrow(true);
dataValidation.setEmptyCellAllowed(true);
dataValidation.setShowPromptBox(true);
dataValidation.createPromptBox("提示", "请选择多个选项，用逗号分隔");

// 将下拉列表应用到单元格
sheet.addValidationData(dataValidation);