content: import org.apache.commons.io.FileUtils;
  import org.apache.poi.hssf.usermodel.HSSFCell;
  import org.apache.poi.hssf.usermodel.HSSFRow;
  import org.apache.poi.hssf.usermodel.HSSFSheet;
  import org.apache.poi.hssf.usermodel.HSSFWorkbook;
  
  import java.io.File;
  import java.io.FileOutputStream;
  import java.io.IOException;
  
  public class PoiExpExcel {
      /**
       * 生成excel文件
       */
      public static void main(String[] args) {
  
          String[] title = {"id", "name", "sex"};
  
          // 创建excel工作簿
          HSSFWorkbook workbook = new HSSFWorkbook();
          // 创建一个工作表sheet
          HSSFSheet sheet = workbook.createSheet();
          // 创建第一行
          HSSFRow row = sheet.createRow(0);
          HSSFCell cell = null;
          // 插入第一行数据id, name, sex
          for (int i = 0; i < title.length; i++) {
              cell = row.createCell(i);
              cell.setCellValue(title[i]);
          }
          // 追加数据
          for (int i = 1; i<= 10; i++){
              HSSFRow nextrow = sheet.createRow(i);
              HSSFCell cell2 = nextrow.createCell(0);
              cell2.setCellValue("a" + i);
              cell2 = nextrow.createCell(1);
              cell2.setCellValue("user" + i);
              cell2 = nextrow.createCell(2);
              cell2.setCellValue("男");
          }
  
          // 创建一个文件
          File file = new File("src/main/resources/output.xls");
          try{
              file.createNewFile();
              // 将excel存盘
              FileOutputStream stream = FileUtils.openOutputStream(file);
              workbook.write(stream);
              stream.close();
          }catch (IOException e){
              e.printStackTrace();
          }
      }
  }
  