读取excel文件到数据库 和 下载 excel文件

Poi解析2003时使用的是HSSFCell，而2007的则是 XSSFCell，是完全不同的两套API

必须先要判断excel的类型，不过 HSSFWorkbook 和 XSSFWorkbook 实现的接口都是一样的Workbook，直接在实例化接口的时候有点区别其他时候没有任何差异。

第一部分是读取excel到数据库

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.text.DecimalFormat;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.LinkedList;
import java.util.List;

import org.apache.poi.hssf.usermodel.HSSFCell;
import org.apache.poi.hssf.usermodel.HSSFDataFormat;
import org.apache.poi.hssf.usermodel.HSSFDateUtil;
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.XSSFCell;
import org.apache.poi.xssf.usermodel.XSSFRow;
import org.apache.poi.xssf.usermodel.XSSFSheet;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;

public class testFile {

public static List<List<Object>> readExcel(File file) throws IOException {
String fileName = file.getName();
String extension = fileName.lastIndexOf(".") == -1 ? "" : fileName.substring(fileName.lastIndexOf(".") + 1);
if ("xls".equals(extension)) {
return read2003Excel(file);
} else if ("xlsx".equals(extension)) {
return read2007Excel(file);
} else {
throw new IOException("不支持的文件类型");
}
}

/**
* 读取 office 2003 excel
*
* @throws IOException
* @throws FileNotFoundException
*/
private static List<List<Object>> read2003Excel(File file) throws IOException {

List<List<Object>> list = new LinkedList<List<Object>>();
Object value = null;
POIFSFileSystem poifsFileSystem = new POIFSFileSystem(new FileInputStream(file));
HSSFWorkbook hssfWorkbook = new HSSFWorkbook(poifsFileSystem);
HSSFSheet hssfSheet = hssfWorkbook.getSheetAt(0);

int rowstart = hssfSheet.getFirstRowNum();
int rowEnd = hssfSheet.getLastRowNum();
int cellStart = 0;
int cellEnd = 0;
for (int i = rowstart; i <= rowEnd; i++) {
List<Object> linked = new LinkedList<Object>();
HSSFRow row = hssfSheet.getRow(i);
if (null == row)
continue;
if (i == 0) {
cellStart = row.getFirstCellNum();
cellEnd = row.getLastCellNum();
}

for (int k = cellStart; k <= cellEnd; k++) {
HSSFCell cell = row.getCell(k);
if (null == cell || null == cell.toString() || "".equals(cell.toString())) {
linked.add("无");
continue;
}

switch (cell.getCellType()) {
case HSSFCell.CELL_TYPE_NUMERIC: // 数字
System.out.print(cell.getNumericCellValue() + " ");
value = cell.getNumericCellValue();
break;
case HSSFCell.CELL_TYPE_STRING: // 字符串

value = cell.getStringCellValue();
break;
case HSSFCell.CELL_TYPE_BOOLEAN: // Boolean

value = cell.getBooleanCellValue();
break;
case HSSFCell.CELL_TYPE_FORMULA: // 公式

value = cell.getCellFormula();
break;
case HSSFCell.CELL_TYPE_BLANK: // 空值

System.out.println(" ");
value = "";// 导入不能为空

break;
default:
value = cell.toString();
}
value = cell.toString();
if (value == null || "".equals(value)) {
value = "无";// 导入不能为空
}
linked.add(value);
}
System.out.print("\n");
list.add(linked);
}
hssfWorkbook.close();
poifsFileSystem.close();
return list;
}

/**
* 读取Office 2007 excel
*/
private static List<List<Object>> read2007Excel(File file) throws IOException {
List<List<Object>> list = new LinkedList<List<Object>>();
// 构造 XSSFWorkbook 对象，strPath 传入文件路径
XSSFWorkbook xwb = new XSSFWorkbook(new FileInputStream(file));
// 读取第一章表格内容
XSSFSheet sheet = xwb.getSheetAt(0);
Object value = null;
XSSFRow row = null;
XSSFCell cell = null;
int counter = 0;
for (int i = sheet.getFirstRowNum(); counter < sheet.getPhysicalNumberOfRows(); i++) {
if (i == 0) {
// 跳过第一行
continue;
}
row = sheet.getRow(i);
if (row == null) {
break;
}
List<Object> linked = new LinkedList<Object>();
for (int j = row.getFirstCellNum(); j < row.getLastCellNum(); j++) {
cell = row.getCell(j);
if (cell == null) {
value = "无";// 导入不能为空
linked.add(value);
continue;
}
DecimalFormat df = new DecimalFormat("0");// 格式化 number String
// 字符
SimpleDateFormat sdf = new SimpleDateFormat("yyyy/MM/dd");// 格式化日期字符串
DecimalFormat nf = new DecimalFormat("0");// 格式化数字

if (cell.getCellType() == XSSFCell.CELL_TYPE_NUMERIC) {
if (HSSFDateUtil.isCellDateFormatted(cell)) {// 处理日期格式、时间格式
SimpleDateFormat sdf2 = null;
if (cell.getCellStyle().getDataFormat() == HSSFDataFormat.getBuiltinFormat("h:mm")) {
sdf2 = new SimpleDateFormat("HH:mm");
} else {// 日期
Date date = cell.getDateCellValue();
value = sdf.format(date);
}
} else
value = cell.toString();
} else
value = cell.toString();

if (value == null || "".equals(value)) {
value = "无";// 导入不能为空
}
linked.add(value);
}
list.add(linked);
}
return list;
}

}第二部分下载excel文件
/**
* 下载Excel文件
* @param 导出的数据对象List-->objList
* @param 模板对象UploadAndDownLoadColumnVo
* @param 文件导出路径path
* */
@Override
public void downLoadExcel(List<Object> objList , List<UploadAndDownLoadColumnVo> uploadAndDownLoadColumnVoList , String path) {
if(StringUtils.isBlank(path)){
throw new ScubeBizException("导出路径错误,导出失败！");
}
String bookName = "";
if(objList==null||objList.size()<=0){
throw new ScubeBizException("要导出的内容为空,导出失败！");
}else{
//创建工作表格对象
HSSFWorkbook workBook = new HSSFWorkbook();
//创建Sheet页
for(int i =0 ; i<uploadAndDownLoadColumnVoList.size() ; i++){
UploadAndDownLoadColumnVo uploadAndDownLoadColumnVo = uploadAndDownLoadColumnVoList.get(i);
bookName = uploadAndDownLoadColumnVo.getBookName();
HSSFSheet sheet = workBook.createSheet(uploadAndDownLoadColumnVo.getSheetName());
HSSFRow row = sheet.createRow(0);
Class<? extends UploadAndDownLoadColumnVo> voClass = uploadAndDownLoadColumnVo.getClass();
try {
Method[] mms = voClass.getDeclaredMethods();
//填充Sheet标题
for(int j = 0 ; j<mms.length ; j++){
Method mm = mms[j];
String methodName = mm.getName();
if(methodName.contains("getColumnName")){
String columnName = (String)mm.invoke(uploadAndDownLoadColumnVo, new Object[]{});
if(columnName!=null){
String index = methodName.replace("getColumnName", "");
int indexNo = Integer.parseInt(index);
HSSFCell cell = row.createCell(indexNo-1);
logger.info("methodName["+methodName+"]value["+columnName+"]index["+index+"]");
cell.setCellValue(columnName);
}
}
}
} catch (Exception e) {
e.printStackTrace();
}
}
//获取填充数据的Sheet
HSSFSheet targetSheet = workBook.getSheetAt(0);
//填充数据
for(int k = 0 ; k<objList.size() ; k++){
Object object = objList.get(k);
Class<? extends Object> objClass = object.getClass();
Method[] mms = objClass.getDeclaredMethods();
HSSFRow targetRow = targetSheet.createRow(k+1);
int fieldIndex = 0;
String fieldValue = "";
for(int i =0 ; i<mms.length ; i++){
Method mm = mms[i];
String mmName = mm.getName();
String setFlg = "1";
try {
if(mmName.contains("get")&&(!mmName.contains("Index"))){
//获取字段值
fieldValue = (String)mm.invoke(object, new Object[]{});
//获取字段索引
String mName = mmName+"Index";
Method temMM = objClass.getMethod(mName , new Class<?>[]{});
fieldIndex = Integer.parseInt(temMM.invoke(
4000
object, new Object[]{}).toString());
setFlg = "0";
}else{
setFlg = "1";
}
} catch (Exception e) {
e.printStackTrace();
}
if(setFlg.equals("0")){
//填充表格
HSSFCell targetCell = targetRow.createCell(fieldIndex);
targetCell.setCellValue(fieldValue);
}
}

}
if(StringUtils.isBlank(bookName)){
bookName = new SimpleDateFormat("yyyMMddHHmmss").format(new Date())+"Export";
}
try {
String fullPath = path+bookName+".xls";
FileOutputStream output = new FileOutputStream(fullPath);
workBook.write(output);
output.flush();
workBook.close();
} catch (Exception e) {
logger.error("导出文件失败！" , e);
}
}

}

public class UploadAndDownLoadColumnVo {

//表格名
String bookName;

//表格Sheet名
String sheetName;

//列名1
String columnName1;

//列名2
String columnName2;

//列名3
String columnName3;

//列名4
String columnName4;

//列名5
String columnName5;

//列名6
String columnName6;

//列名7
String columnName7;

//列名8
String columnName8;

//列名9
String columnName9;

//列名10
String columnName10;

//列名11
String columnName11;

//列名12
String columnName12;

//列名13
String columnName13;

//列名14
String columnName14;

//列名15
String columnName15;

//列名16
String columnName16;

//列名17
String columnName17;

//列名18
String columnName18;

//列名19
String columnName19;

//列名20
String columnName20;

}

省略get、set方法。

这两个都是项目上用到的，很好用。