利用POI实现数据库导出Excel

package student; import java.io.FileOutputStream; import java.text.SimpleDateFormat; import java.util.ArrayList; import java.util.List; import org.apache.poi.hssf.usermodel.HSSFCell; import org.apache.poi.hssf.usermodel.HSSFCellStyle; import org.apache.poi.hssf.usermodel.HSSFRow; import org.apache.poi.hssf.usermodel.HSSFSheet; import org.apache.poi.hssf.usermodel.HSSFWorkbook; public class CreateSimpleExcelToDisk { /** * @功能：手工构建一个简单格式的Excel */ private static List<Student> getStudent() throws Exception { List list = new ArrayList(); SimpleDateFormat df = new SimpleDateFormat("yyyy-mm-dd"); Student user1 = new Student(1, "张三", 16, df.parse("1997-03-12")); Student user2 = new Student(2, "李四", 17, df.parse("1996-08-12")); Student user3 = new Student(3, "王五", 26, df.parse("1985-11-12")); list.add(user1); list.add(user2); list.add(user3); return list; } public static void main(String[] args) throws Exception { // 第一步，创建一个webbook，对应一个Excel文件 HSSFWorkbook wb = new HSSFWorkbook(); // 第二步，在webbook中添加一个sheet,对应Excel文件中的sheet HSSFSheet sheet = wb.createSheet("学生表一"); // 第三步，在sheet中添加表头第0行,注意老版本poi对Excel的行数列数有限制short HSSFRow row = sheet.createRow((int) 0); // 第四步，创建单元格，并设置值表头 设置表头居中 HSSFCellStyle style = wb.createCellStyle(); style.setAlignment(HSSFCellStyle.ALIGN_CENTER); // 创建一个居中格式 HSSFCell cell = row.createCell(0); cell.setCellValue("学号"); cell.setCellStyle(style); cell = row.createCell(1); cell.setCellValue("姓名"); cell.setCellStyle(style); cell = row.createCell(2); cell.setCellValue("年龄"); cell.setCellStyle(style); cell = row.createCell(3); cell.setCellValue("生日"); cell.setCellStyle(style); // 第五步，写入实体数据 实际应用中这些数据从数据库得到， List list = CreateSimpleExcelToDisk.getStudent(); for (int i = 0; i < list.size(); i++) { row = sheet.createRow((int) i + 1); Student stu = (Student) list.get(i); // 第四步，创建单元格，并设置值 row.createCell(0).setCellValue((double) stu.getId()); row.createCell(1).setCellValue(stu.getName()); row.createCell(2).setCellValue((double) stu.getAge()); cell = row.createCell(3); cell.setCellValue(new SimpleDateFormat("yyyy-mm-dd").format(stu .getBirth())); } // 第六步，将文件存到指定位置 try { FileOutputStream fout = new FileOutputStream("E:/students.xls"); wb.write(fout); fout.close(); } catch (Exception e) { e.printStackTrace(); } } }