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<dependency>
<groupId>org.apache.poi</groupId>
<artifactId>poi</artifactId>
<version>4.0.1</version>
</dependency>
<dependency>
<groupId>org.apache.poi</groupId>
<artifactId>poi-ooxml</artifactId>
<version>4.0.1</version>
</dependency>
<dependency>
（1）读取Excel
InputStream inputStream = file.getInputStream();
XSSFWorkbook xssfWorkbook = new XSSFWorkbook(inputStream);
（2）获取sheet的个数：int getNumberOfSheets()
//获取sheet的个数
int numberOfSheets = xssfWorkbook.getNumberOfSheets();
（3）获取sheet的名称：String getSheetName(int sheetIndex)
String sheetName = xssfWorkbook.getSheetName(sheetId);
（4）根据名称获得sheet：XSSFSheet getSheet(String sheetName)
XSSFSheet sheet = xssfWorkbook.getSheet(sheetName);
（5）获得shhet最大行数
int lastRowNum = sheet.getLastRowNum();
（6）获得单行最大列数
short lastCellNum = rowData.getLastCellNum();
（7）获得某一行：XSSFRow getRow(int rowIndex)
XSSFRow rowData = sheet.getRow(rowNum);
（8）获得某行某个单元格：XSSFCell getCell(int cellIndex)
XSSFCell cell = rowData.getCell(2);
（1）创建一个Excel
XSSFWorkbook outputWorkbook = new XSSFWorkbook();
（2）创建一个sheet
XSSFSheet outputSheet = outputWorkbook.createSheet();
（4）创建一行：XSSFRow createRow(int rowIndex)
XSSFRow newRow = sheet.createRow(lastRowNum + 1);
（5）创建单元格：XSSFCell createCell(int cellIndex)
XSSFCell newCell = newRow.createCell(i);
（6）设置单元格数据：setCellVaule(String/double/Date/boolean...)
newCell.setCellValue(String data);