java poi向excel中追加內容

.xlsx使用HSSFWorkbook
.xls使用XSSFWorkbook

導入

import org.apache.poi.hssf.usermodel.HSSFRow;
import org.apache.poi.hssf.usermodel.HSSFSheet;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.poifs.filesystem.POIFSFileSystem;
import org.apache.poi.xssf.usermodel.XSSFRow;
import org.apache.poi.xssf.usermodel.XSSFSheet;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
import org.junit.Test;

import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.List;

代碼

	 @Test
public void testExcel(){
        FileInputStream fs;
        String url = "本地路徑";
        try {
            fs = new FileInputStream(url);
            System.out.println(url.substring(url.lastIndexOf(".")));
            if (!url.substring(url.lastIndexOf(".")).equals(".xlsx")) {
                POIFSFileSystem ps = new POIFSFileSystem(fs); //使用POI提供的方法得到excel的信息
                HSSFWorkbook wb = new HSSFWorkbook(ps);
                HSSFSheet sheet = wb.getSheetAt(0); //獲取到工作表，因為一個excel可能有多個工作表
                HSSFRow row = sheet.getRow(0);
                int hang = 0;
                if ("".equals(row) || row == null) {
                    hang = 0;
                } else {
                    hang = sheet.getLastRowNum();
                    hang = hang + 1;
                }
                //分別得到最后一行的行號，和一條記錄的最后一個單元格
                FileOutputStream out = new FileOutputStream(url); //向d://test.xls中寫數據
                row = sheet.createRow((short) (hang)); //在現有行號后追加數據
                row.createCell(0).setCellValue("111"); //設置第一個（從0開始）單元格的數據
                row.createCell(1).setCellValue("222"); //設置第二個（從0開始）單元格的數據

                System.out.println(row.getPhysicalNumberOfCells() + " " + row.getLastCellNum());
                out.flush();
                wb.write(out);
                out.close();
            } else {
                XSSFWorkbook wb = new XSSFWorkbook(fs);
                XSSFSheet sheet = wb.getSheetAt(0); //獲取到工作表，因為一個excel可能有多個工作表
                XSSFRow row = sheet.getRow(0);
                int hang = 0;
                if ("".equals(row) || row == null) {
                    hang = 0;
                } else {
                    hang = sheet.getLastRowNum();
                    hang = hang + 1;
                }
                //分別得到最后一行的行號，和一條記錄的最后一個單元格
                FileOutputStream out = new FileOutputStream(url); //向d://test.xls中寫數據
                row = sheet.createRow((short) (hang)); //在現有行號后追加數據
                row.createCell(0).setCellValue("111"); //設置第一個（從0開始）單元格的數據
                row.createCell(1).setCellValue("222"); //設置第二個（從0開始）單元格的數據
                System.out.println(row.getPhysicalNumberOfCells() + " " + row.getLastCellNum());
                out.flush();
                wb.write(out);
                out.close();
            }

        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }