1.导入Excel文件到数据的类
后台代码：
@Overried
public void upFile(MultipartFile file){
SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
try {
InputStream in = file.getInputStream();
Workbook work = new XSSFWorkbook(in);
//第一个sheet
Sheet sheet1 = work.getSheetAt(0);
//有效行数
int rowNubms = sheet1.getPhysicalNumberOfRows();
for(int i=1;i<rowNubms;i++){
Row rowi = sheet1.getRow(i);
if(rowi == null){
continue;
}
//创建数据库表对应的实体类
FalseOfferings offer = new FalseOfferings();
Cell cell1 = rowi.getCell(0);
Cell cell2 = rowi.getCell(1);
Cell cell3 = rowi.getCell(2);
Cell cell4 = rowi.getCell(3);
Cell cell5 = rowi.getCell(4);
Cell cell6 = rowi.getCell(5);
//此处判断为null，以防get值的时候 报空指针
Long offeringId = (cell1 != null)?Long.parseLong(getCellValue(cell1)):null;
String offeringName =(cell2 != null)? getCellValue(cell2):null;
Date createDate = (cell3 != null)?format.parse(getCellValue(cell3)):null;
Long categoryId = (cell4 != null)?Long.parseLong(getCellValue(cell4)):null;
String fromdbs = (cell5 != null)?getCellValue(cell5):null;
String area = (cell6 != null)?getCellValue(cell6):null;
//填充实体类
offer.setOfferingId(offeringId);
offer.setOfferingName(offeringName);
offer.setCategoryId(categoryId);
offer.setFromdbs(fromdbs);
offer.setArea(area);
offer.setCreateDate(createDate);
//使用JPA 保存到数据库中
falseOfferResposity.save(offer);
in.close(); //关闭流
}
} catch (Exception e) {
e.printStackTrace();
}
}
//根据Excel表格类型，使用不同的方法去取值
private String getCellValue(Cell cell){
String value ="";
switch (cell.getCellType()){
case Cell.CELL_TYPE_STRING:
value = cell.getStringCellValue();
break;
case Cell.CELL_TYPE_NUMERIC:
value = String.valueOf(cell.getNumericCellValue());
break;
case Cell.CELL_TYPE_BLANK:
value = "";
break;
case Cell.CELL_TYPE_BOOLEAN:
value = String.valueOf(cell.getBooleanCellValue());
break;
case Cell.CELL_TYPE_ERROR:
value = String.valueOf(cell.getErrorCellValue());
break;
case Cell.CELL_TYPE_FORMULA:
value = String.valueOf(cell.getCellFormula());
break;
}
return value;
}前台代码 HTML：
基于原有的file类型的input样式比较丑，所以此处使用假的 input 文本框 充当
<div>
<input type="text" name="wenJian" readonly="readonly" id="wenJian"/>
<button ng-click="ctrl.liuLan()">浏览</button>
<button ng-click="ctrl.daoRu()">确认导入</button>
<form id="upForm" action="fileTariff/upFile" method="post" enctype="multipart/form-data" style="display: none">
<input type="file" name="file" accept=".xls,.xlsx" id="file"/>
</form>
</div>
<div>
<input type="text" name="wenJian" readonly="readonly" id="wenJian"/>
<button ng-click="ctrl.liuLan()">浏览</button>
<button ng-click="ctrl.daoRu()">确认导入</button>
<form id="upForm" action="fileTariff/upFile" method="post" enctype="multipart/form-data" style="display: none">
<input type="file" name="file" accept=".xls,.xlsx" id="file"/>
</form>
</div>前台JS 用的是AngularJS 框架，代码如下，大致就是用来触发事件，向后台发送请求的
self.liuLan = function(){
$('#file').click();
};
$('#file').change(function() {
$('#wenJian').val($('#file').val()) ;
});
self.daoRu = function(){
$('#upForm').submit();
};
self.liuLan = function(){
$('#file').click();
};
$('#file').change(function() {
$('#wenJian').val($('#file').val()) ;
});
self.daoRu = function(){
$('#upForm').submit();
};2.导出为Excel文件：
/**
* POI : 导出数据，存放于Excel中
* @param os 输出流 (action: OutputStream os = response.getOutputStream();)
* @param employeeInfos 要导出的数据集合
*/
public static void exportEmployeeByPoi(OutputStream os, List<EmployeeInfo> employeeInfos) {
try {
//创建Excel工作薄
HSSFWorkbook book = new HSSFWorkbook();
//在Excel工作薄中建一张工作表
HSSFSheet sheet = book.createSheet("员工信息");
//第一行为标题行
HSSFRow row = sheet.createRow(0);//创建第一行
HSSFCell cell0 = row.createCell(0);
HSSFCell cell1 = row.createCell(1);
HSSFCell cell2 = row.createCell(2);
HSSFCell cell3 = row.createCell(3);
HSSFCell cell4 = row.createCell(4);
//定义表头单元格为字符串类型
cell0.setCellType(HSSFCell.CELL_TYPE_STRING);
cell1.setCellType(HSSFCell.CELL_TYPE_STRING);
cell2.setCellType(HSSFCell.CELL_TYPE_STRING);
cell3.setCellType(HSSFCell.CELL_TYPE_STRING);
cell4.setCellType(HSSFCell.CELL_TYPE_STRING);
//在单元格中输入数据
cell0.setCellValue("员工编号");
cell1.setCellValue("员工姓名");
cell2.setCellValue("员工性别");
cell3.setCellValue("出生日期");
cell4.setCellValue("身份证号");
//循环导出数据到excel中
for(int i = 0; i < employeeInfos.size(); i++) {
EmployeeInfo employeeInfo = employeeInfos.get(i);
//创建第i行
HSSFRow rowi = sheet.createRow(i + 1);
//在第i行的相应列中加入相应的数据
rowi.createCell(0).setCellValue(employeeInfo.getEmployeeNumber());
rowi.createCell(1).setCellValue(employeeInfo.getFullName());
//处理性别(M:男 F:女)
String sex = null;
if("M".equals(employeeInfo.getSex())) {
sex = "男";
}else {
sex = "女";
}
rowi.createCell(2).setCellValue(sex);
//对日期的处理
if(employeeInfo.getDateOfBirth() != null && !"".equals(employeeInfo.getDateOfBirth())){
java.text.DateFormat format1 = new SimpleDateFormat("yyyy-MM-dd");
rowi.createCell(3).setCellValue(format1.format(employeeInfo.getDateOfBirth()));
}
rowi.createCell(4).setCellValue(employeeInfo.getNationalIdentifier());
}
//写入数据 把相应的Excel 工作簿存盘
book.write(os);
} catch (IOException e) {
e.printStackTrace();
}
}