Exception in thread main javalangIllegalArgumentException The workbook already contains a sheet named Sheet2 at orgapachepoixssfusermodelXSSFWorkbookvalidateSheetNameXSSFWorkbookjava952 at orgapachepo

：在创建新的工作表之前，先检查工作簿中是否已经存在同名的工作表，如果存在，则给新工作表命名时使用不同的名称。代码示例：

if (workbook.getSheetIndex("Sheet2") == -1) { Sheet sheet2 = workbook.createSheet("Sheet2"); } else { Sheet sheet2 = workbook.createSheet("Sheet2_new"); }