Excel导入导出详解
excel导入
目的:上传一个excel文件，读取到里面的数据并做相关操作
- 页面部分
页面部分需要注意form的提交类型必须是 enctype=”multipart/form-data”
type="file" name="fileUploader" class="form-control" placeholder="" accept="application/msexcel">
- 后台部分
1.准备工作，创建临时存放文件夹，分配大小，把request中得到FileItem
File userFolder = FileUtil.getFile(tempFilesFolder + userLoginId + "/");
if (!userFolder.exists()) {
userFolder.mkdirs();
}
FileItemFactory fit=new DiskFileItemFactory(10240, userFolder);
ServletFileUpload dfu = new ServletFileUpload(fit);
fileItems = UtilGenerics.checkList(dfu.parseRequest(request));2.把提交上来的文件数据放到我们的临时文件中
private boolean storeAcctgFile() throws IOException {
FileItem fi = null;
FileItem pricatFi = null;
byte[] pricatBytes = {};
// store the file
for (int i = 0; i < fileItems.size(); i++) {
fi = fileItems.get(i);
String fieldName = fi.getFieldName();
if (fieldName.equals("fileUploader")) {
pricatFi = fi;
pricatBytes = pricatFi.get();
Path path = Paths.get(fi.getName());
acctgFile = new File(tempFilesFolder + userLoginId + "/" + path.getFileName().toString());
FileOutputStream fos = new FileOutputStream(acctgFile);
fos.write(pricatBytes);
fos.flush();
fos.close();
session.setAttribute(AcctgParseExcelHtmlThread.ACCTG_FILE, acctgFile.getAbsolutePath());
}
}
return true;
}3.从临时文件excel中一行行读出数据写入到数据库中
**//整合方法**
private void parseAcctgExcel() {
XSSFWorkbook workbook = null;
try {
// 2. store the pricat excel file
storeAcctgFile();
// 3. read the pricat excel file
FileInputStream is = new FileInputStream(acctgFile);
try {
workbook = new XSSFWorkbook(is);
} catch(IOException e) {
deletePricatFile = true;
return;
} catch(POIXMLException e) {
deletePricatFile = true;
return;
}
XSSFSheet sheet = workbook.getSheetAt(0);
containsDataRows(sheet);
// parse row by row and store the contents into xml file(s)
parseRowByRow(sheet);
deletePricatFile = true;
} catch (IOException e) {
getReport().println(e);
Debug.logError(e, module);
} finally {
if (UtilValidate.isNotEmpty(fileItems)) {
// remove tmp files
FileItem fi = null;
for (int i = 0; i < fileItems.size(); i++) {
fi = fileItems.get(i);
fi.delete();
}
}
if (deletePricatFile && acctgFile != null && acctgFile.exists() && acctgFile.isFile()) {
acctgFile.delete();
}
if (workbook != null) {
try {
workbook.close();
} catch (IOException e) {
Debug.logError(e, module);
}
}
}
}
**//处理数据**
private void parseRowByRow(XSSFSheet sheet) {
int rows = sheet.getPhysicalNumberOfRows();
List colNames = ColNamesList.get(acctgFileVersion);
int colNumber = colNames.size();
for (int i = headerRowNo + 1; i < rows; i++) {
getReport().print("(" + (i + 1) + ") ", InterfaceReport.FORMAT_NOTE);
XSSFRow row = sheet.getRow(i);
if (UtilValidate.isEmpty(row)) {
continue;
}
List excel导出
目的：看到一个列表，生成一个具体模板的excel表格放在某个位置，想下载的时候可以下载
1.提前放好模板 excel文件（就是导出列表多个头，头部分提前放好），并拷贝到数据excel文件中。–这步可以不要，看具体操作
//模板
String path;
File templateFile ;
try {
// 导出模板的地址
path = PricatPath +"Template_v10.xlsx";
templateFile = new File(path);
} catch (MalformedURLException e) {
templateFile = null;
}
//数据excel
orderExportFile = FileUtil.getFile(tempFilesFolder+"/"+exportType+"/" + sequenceNum + ".xlsx");
//移动数据
copyFile(templateFile, exportFile)
public static boolean copyFile(File srcFile, File destFile) {
FileInputStream fi = null;
FileOutputStream fo = null;
FileChannel in = null;
FileChannel out = null;
try {
fi = new FileInputStream(srcFile);
fo = new FileOutputStream(destFile);
in = fi.getChannel();//得到对应的文件通道
out = fo.getChannel();//得到对应的文件通道
in.transferTo(0, in.size(), out);//连接两个通道，并且从in通道读取，然后写入out通道
return true;
} catch (IOException e) {
e.printStackTrace();
return false;
} finally {
try {
fi.close();
in.close();
fo.close();
out.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}2.查询得到数据，XSSFWorkbook，放入数据，最好写入到导出文件
public void exportExcel(Map parameters) {
XSSFWorkbook workbook = null;
try {
// 1. read the pricat excel file
FileInputStream is = new FileInputStream(exportFile);
// 2. use POI to load this bytes
try {
workbook = new XSSFWorkbook(is);
} catch (IOException e) {
return;
} catch (POIXMLException e) {
return;
}
isNumOfSheetsOK(workbook);
XSSFSheet sheet = workbook.getSheetAt(0);
// 这里会给AbstractReportThread 中的 版本赋值，后面获取列名的时候会用到这个值
if (!isVersionSupported(sheet)) {
return;
}
// 准备数据 根据穿进去的map参数查询得到一个list数据，放在公用变量中
prepareData(parameters);
// 4. fill data in the 1st sheet
fillSheet(sheet);
// 5. write the workbook to file
writeWorkbookToFile(workbook, exportFile);
// 6. clean up the log files and exported Excel files
cleanupLogAndExportedExcel(parameters.get("exportType")[0]);
} catch (IOException e) {
report.println(e);
Debug.logError(e, module);
} finally {
if (workbook != null) {
try {
workbook.close();
} catch (IOException e) {
Debug.logError(e, module);
}
}
}
}
//fillSheet---调用 fillDataRowByRow(sheet, data, headerRowNo, exportFileVersion);
//fillRowDataCellByCell formatRowData这里根据不同的version获取具体列
int i = headerRowNo + 1;
int j = 0;
boolean useAlterStyle = false;
for (类型 rowData : data) {
XSSFRow row = sheet.createRow(i);
List 下载文件
public static final String ReconciliationTempName = "文件名.xlsx";
Path path = Paths.get(URL地址);
byte[] bytes=Files.readAllBytes(path);
//application/octet-stream 二进制流，下载时不知道类型
streamContentToBrowser(response, bytes,"application/octet-stream", URLEncoder.encode(ReconciliationTempName,"UTF-8"));
public static void streamContentToBrowser(HttpServletResponse response, byte[] bytes, String contentType, String fileName) throws IOException {
// tell the browser not the cache
setResponseBrowserProxyNoCache(response);
// set the response info
response.setContentLength(bytes.length);
if (contentType != null) {
response.setContentType(contentType);
}
if (fileName != null) {
response.setHeader("Content-Disposition", "attachment;filename=" + fileName);
}
// create the streams
OutputStream out = response.getOutputStream();
InputStream in = new ByteArrayInputStream(bytes);
// stream the content
try {
streamContent(out, in, bytes.length);
} catch (IOException e) {
in.close();
out.close(); // should we close the ServletOutputStream on error??
throw e;
}
// close the input stream
in.close();
// close the servlet output stream
out.flush();
out.close();
}
public static void setResponseBrowserProxyNoCache(HttpServletResponse response) {
long nowMillis = System.currentTimeMillis();
response.setDateHeader("Expires", nowMillis);
response.setDateHeader("Last-Modified", nowMillis); // always modified
response.setHeader("Cache-Control", "no-store, no-cache, must-revalidate"); // HTTP/1.1
response.addHeader("Cache-Control", "post-check=0, pre-check=0, false");
response.setHeader("Pragma", "no-cache"); // HTTP/1.0
}
public static void streamContent(OutputStream out, InputStream in, int length) throws IOException {
int bufferSize = 512; // same as the default buffer size; change as needed
// make sure we have something to write to
if (out == null) {
throw new IOException("Attempt to write to null output stream");
}
// make sure we have something to read from
if (in == null) {
throw new IOException("Attempt to read from null input stream");
}
// make sure we have some content
if (length == 0) {
throw new IOException("Attempt to write 0 bytes of content to output stream");
}
// initialize the buffered streams
BufferedOutputStream bos = new BufferedOutputStream(out, bufferSize);
BufferedInputStream bis = new BufferedInputStream(in, bufferSize);
byte[] buffer = new byte[length];
int read = 0;
try {
while ((read = bis.read(buffer, 0, buffer.length)) != -1) {
bos.write(buffer, 0, read);
}
} catch (IOException e) {
Debug.logError(e, "Problem reading/writing buffers", module);
bis.close();
bos.close();
throw e;
} finally {
if (bis != null) {
bis.close();
}
if (bos != null) {
bos.flush();
bos.close();
}
}
}