java讀取與寫入excel(.xls .xlsx)
阿新 • • 發佈:2019-02-13
maven依賴:
首先在maven中新增:
<!-- https://mvnrepository.com/artifact/org.apache.poi/poi --> <dependency> <groupId>org.apache.poi</groupId> <artifactId>poi-ooxml</artifactId> <version>3.10-FINAL</version> </dependency>
讀取:
java讀取excel的思路很簡單,先讀取行(HXXFRow類或XSSFRow類),然後得到列(.getRow(列下標)),這樣就可以定位一個單元格了
寫入:import org.apache.poi.hssf.usermodel.HSSFSheet; import org.apache.poi.hssf.usermodel.HSSFWorkbook; import org.apache.poi.xssf.usermodel.XSSFRow; import org.apache.poi.xssf.usermodel.XSSFSheet; import org.apache.poi.xssf.usermodel.XSSFWorkbook; import java.io.FileInputStream; import java.io.InputStream; /**使用例子 * ReadExcel excel = new ReadExcel("D:\\myexcel.xlsx"); * String[] firstLine = excel.readLine(0);//得到第一行資料 * String[] firstLine = excel.readLine(1);//得到第二行資料 */ public class ReadExcel { private HSSFSheet hssfSheet;//.xls private XSSFSheet xssfSheet;//.xlsx public int getAllRowNumber() { return xssfSheet.getLastRowNum(); } /*讀取 excel 下標為 rowNumber 的那一行的全部資料*/ public String[] readLine(int rowNumber) { XSSFRow row = xssfSheet.getRow(rowNumber); if (row != null) { String[] resultStr = new String[row.getLastCellNum()]; for (int i = 0; i < row.getLastCellNum(); i++) { resultStr[i] = row.getCell(i).getStringCellValue(); } return resultStr; } return null; } public ReadExcel(String excelPath) throws Exception { String fileType = excelPath.substring(excelPath.lastIndexOf(".") + 1, excelPath.length()); // 建立工作文件物件 InputStream in = new FileInputStream(excelPath); HSSFWorkbook hssfWorkbook = null;//.xls XSSFWorkbook xssfWorkbook = null;//.xlsx //根據字尾建立讀取不同型別的excel if (fileType.equals("xls")) { hssfWorkbook = new HSSFWorkbook(in);//它是專門讀取.xls的 } else if (fileType.equals("xlsx")) { xssfWorkbook = new XSSFWorkbook(in);//它是專門讀取.xlsx的 } else { throw new Exception("文件格式字尾不正確!!!"); } /*這裡預設只讀取第 1 個sheet*/ if (hssfWorkbook != null) { this.hssfSheet = hssfWorkbook.getSheetAt(0); } else if (xssfWorkbook != null) { this.xssfSheet = xssfWorkbook.getSheetAt(0); } } }
java寫入excel的思路是:
1.先建立一個Workbook類,然後根據想要建立的文件型別來new 不同型別的例項(.xls就是new HSSFWorkbook() , 而.xlsx是new XSSFWorkbook()),
2.建立好文件物件後,建立第一張表(workbook.createSheet("String型別的表名稱"))
3.然後在這張表(sheet)中的指定行號中建立行(sheet.createRow(int型別的指定行號))
4.在這行中指定一個列號,用來指定具體單元格的座標(row.createCell(int型別的列號))
5.寫入資料(cell.setCellValue(寫入的內容))
package excelUtils;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.ss.usermodel.Cell;
import org.apache.poi.ss.usermodel.Row;
import org.apache.poi.ss.usermodel.Sheet;
import org.apache.poi.ss.usermodel.Workbook;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
import java.io.FileOutputStream;
import java.io.OutputStream;
public class WriteExcel {
private String pathname;
private Workbook workbook;
private Sheet sheet1;
/**使用栗子
* WriteExcel excel = new WriteExcel("D:\\myexcel.xlsx");
* excel.write(new String[]{"1","2"}, 0);//在第1行第1個單元格寫入1,第一行第二個單元格寫入2
*/
public void write(String[] writeStrings, int rowNumber) throws Exception {
//將內容寫入指定的行號中
Row row = sheet1.createRow(rowNumber);
//遍歷整行中的列序號
for (int j = 0; j < writeStrings.length; j++) {
//根據行指定列座標j,然後在單元格中寫入資料
Cell cell = row.createCell(j);
cell.setCellValue(writeStrings[j]);
}
OutputStream stream = new FileOutputStream(pathname);
workbook.write(stream);
stream.close();
}
public WriteExcel(String excelPath) throws Exception {
//在excelPath中需要指定具體的檔名(需要帶上.xls或.xlsx的字尾)
this.pathname = excelPath;
String fileType = excelPath.substring(excelPath.lastIndexOf(".") + 1, excelPath.length());
//建立文件物件
if (fileType.equals("xls")) {
//如果是.xls,就new HSSFWorkbook()
workbook = new HSSFWorkbook();
} else if (fileType.equals("xlsx")) {
//如果是.xlsx,就new XSSFWorkbook()
workbook = new XSSFWorkbook();
} else {
throw new Exception("文件格式字尾不正確!!!");
}
// 建立表sheet
sheet1 = workbook.createSheet("sheet1");
}
}