java使用POI jar包读写xls文件

public class PersonXLS {

public static void main(String[] args) throws IOException {

Workbook newExcel=new HSSFWorkbook();//创建一个excel
DBUtil dbUtil=new DBUtil();//数据库工具类
Sheet newSheet0=newExcel.createSheet("Person Info");//创建一个sheet
String[] title={"MAP_ID","PERSON_CODE","PERSON_NAME","SEX","INSERT_TIME","UPDATE_TIME","POSITION","SALARY","DEPT"};//表头
SimpleDateFormat sdf;
Row newRow0=newSheet0.createRow(0);//创建表头
int i=0;
for(String s:title){//写入表头
Cell cell=newRow0.createCell(i++);
cell.setCellValue(s);
}
long sql_begin = System.currentTimeMillis();
dbUtil.getConn();//数据库连接
ArrayList<Person> persons=dbUtil.getPersonAllRecords();//获取记录
sdf=new SimpleDateFormat("MM/dd/yyyy");
for(i=0;i<persons.size();i++){//写入记录
Row newRow=newSheet0.createRow(i+1);
newRow.createCell(0).setCellValue(persons.get(i).getMap_id());
newRow.createCell(1).setCellValue(persons.get(i).getPerson_code());
newRow.createCell(2).setCellValue(persons.get(i).getPerson_name());
newRow.createCell(3).setCellValue(persons.get(i).getSex());
newRow.createCell(4).setCellValue(sdf.format(persons.get(i).getInsert_time()));
newRow.createCell(5).setCellValue(sdf.format(persons.get(i).getUpdate_time()));
newRow.createCell(6).setCellValue(persons.get(i).getPosition());
newRow.createCell(7).setCellValue(persons.get(i).getSalary());
newRow.createCell(8).setCellValue(persons.get(i).getDept());
}
sdf=new SimpleDateFormat("yyyyMMddHHmmss");
FileOutputStream fos=new FileOutputStream("PersonInfo"+sdf.format(new Date())+System.currentTimeMillis()+".xls");//创建
newExcel.write(fos);//向输入流写入数据
System.out.println("sql cost :"+(System.currentTimeMillis()-sql_begin)+"ms.");//数据操作花费时间
}
}