export content to a text file using java with save dialog - java

i have a result set which has got some values, i want to export the data which is there in result set as a text file with the save dialog.
how to do this in java?.
I have done the above requirement for excel and java like the following.
response.setContentType("application/vnd.ms-excel");
response.setHeader("Content-disposition", "attachment; filename=\"" + reportName + ".xls\"");
and
response.setHeader("Content-disposition", "attachment; filename=\"" + reportName + ".pdf\"");
response.setContentType("application/pdf");
UPDATE :
if(exportTo.equals("text")){
response.setContentType("text/plain");
response.setHeader("Content-disposition", "attachment; filename=\"" + reportName + ".txt\"");
try {
} catch (Exception e) {
// TODO: handle exception
}
}
in this
in try block how to set the contents which are avilable from resultset to a output stream and make it available.

the only difference is this :
response.setContentType("text/plain");
You can see a full example here ( http://www.mkyong.com/servlet/servlet-code-to-download-text-file-from-website-java/ )
UPDATE
This is a demo that I have developed and tested and works perfectly fine:
public class ServletDownloadDemo extends HttpServlet {
private static final int BYTES_DOWNLOAD = 1024;
public void init(ServletConfig config) throws ServletException {
super.init(config);
}
public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException,
IOException {
response.setContentType("text/plain");
response.setHeader("Content-Disposition", "attachment;filename=downloadname.txt");
String s = "Test\n\nText file contects!!";
InputStream input = new ByteArrayInputStream(s.getBytes("UTF8"));
int read = 0;
byte[] bytes = new byte[BYTES_DOWNLOAD];
OutputStream os = response.getOutputStream();
while ((read = input.read(bytes)) != -1) {
os.write(bytes, 0, read);
}
os.flush();
os.close();
}
}
It downloads a text file named downloadname.txt with the contents of String s.
UPDATE 2
String s = "";
while (rs.next()) {
s += rs.getString("column_name");
}
if (exportTo.equals("text")) {
response.setContentType("text/plain");
response.setHeader("Content-Disposition", "attachment;filename=downloadname.txt");
try {
InputStream input = new ByteArrayInputStream(s.getBytes("UTF8"));
int read = 0;
byte[] bytes = new byte[BYTES_DOWNLOAD];
OutputStream os = response.getOutputStream();
//data form resultset
while ((read = input.read(bytes)) != -1) {
os.write(bytes, 0, read);
}
os.flush();
os.close();
} catch (Exception e) {
// TODO: handle exception
}
}
You have to populate your ResultSet and place what you need in String s. That's all.

Related

How to overwrite existing file during file download rather than create a new file

I am using GWT to do file upload, question, how to just overwrite existing file if exists rather create a new file, ex, file(1).doc. Here is my server side code.
protected void service(HttpServletRequest request,
HttpServletResponse response) throws ServletException, IOException {
try {
String modelPath = AutoConstants.PREFIX + "/var/models/";
File file = new File(modelPath + "/" + MODEL_NAME);
if (file.exists()) {
ServletOutputStream out = response.getOutputStream();
DataInputStream in = new DataInputStream(new FileInputStream(
file));
response.setHeader("Pragma", "public");
response.setHeader("Cache-Control",
"must-revalidate, post-check=0, pre-check=0");
response.setHeader("Content-Length",
String.valueOf(file.length()));
response.setHeader("Content-Disposition",
"attachment; fileName=\"" + MODEL_NAME + "\"");
int i = 0;
int BUFSIZE = 8192;
byte[] bbuf = new byte[BUFSIZE];
while ((in != null) && ((i = in.read(bbuf)) != -1)) {
out.write(bbuf, 0, i);
}
in.close();
out.flush();
}
} catch (Exception e) {
logger.error("Exception.getModel", e);
throw new ServletException(e.getMessage());
}
}

Show content of File

i would like to open/show the file content in a browser but i dosen't work.
This is my code:
#WebServlet("/Download")
public class Download extends HttpServlet {
private static final long serialVersionUID = 1L;
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
ByteArrayOutputStream baos = new ByteArrayOutputStream();
String name = request.getParameter("id");
String sep = File.separator;
File file = new File("C:" + sep + "FILE" + sep + name);
if(!file.exists())
{
response.getWriter().print("File not found");
return;
}
InputStream in = new FileInputStream(file);
byte[] buffer = new byte[4096];
int i = 0;
while((i = in.read(buffer)) != -1)
{
baos.write(buffer, 0, i);
}
response.setContentType("application/pdf");
response.setContentLength(baos.size());
response.setHeader("Content-Disposition", "inline; filename=help.pdf");
response.setHeader("Cache-Control", "cache, must-revalidate");
response.setHeader("Pragma", "public");
BufferedOutputStream bos = new BufferedOutputStream(response.getOutputStream());
in.close();
baos.writeTo(bos);
baos.flush();
bos.flush();
bos.close();
}
}
I try to open that file with a servlet class.
I browser debugger i can see that response is coming in, usually in this format(JVBERi0xLjMNMSAwIG9iag08PC9UeXBl...).
Thanks for helping me
EDIT
on the jsp site i call the servlet with an AJAX call, looks like this where 'id' is the fileName which the user want to open.
function downloadFile(id) {
$.ajax({
url:"Download",
type:"POST",
data:"id="+id
});
}
i think you should add this code inside your ajax call in downloadFile(id) function.
success:function(response){
$("#<Some_SPAN_OR_TextAreaID>").show();
$("#<Some_SPAN_OR_TextAreaID").html(response.responseText);
}

How to download file in browser using spring mvc?

I have file on the server & that I want to download on my machine using browser. But I am not getting an option from browser to download the file.
My code is
JSP
<div id="jqgrid">
<table id="grid"></table>
<div id="pager"></div>
</div>
JS
jq("#grid").jqGrid({
....
onCellSelect: function(rowid, index, contents, event) {
...
var fileName = jQuery("#grid").jqGrid('getCell',rowid,'fileName');
$scope.downloadFile(fileName);
}
});
$scope.downloadFile = function(fileName) {
$http({
url: "logreport/downLoadFile",
method: "GET",
params: {"fileName": fileName}
});
};
Controller
#RequestMapping(value = "/downLoadFile", method = RequestMethod.GET)
public void downLoadFile(HttpServletRequest request, HttpServletResponse response) {
try {
String fileName = request.getParameter("fileName");
File file = new File(filePath +"//"+fileName);
InputStream in = new BufferedInputStream(new FileInputStream(file));
response.setContentType("application/xlsx");
response.setHeader("Content-Disposition", "attachment; filename="+fileName+".xlsx");
ServletOutputStream out = response.getOutputStream();
IOUtils.copy(in, out);
response.flushBuffer();
} catch (Exception e) {
e.printStackTrace();
}
}
I am not getting any exception but not sure why browser dialog is not opening to download the file. Also where is it exactly downloading the file?
#SotiriosDelimanolis was right. File download is not possible using ajax request.
Simply use 'window.location'.
$scope.downloadFile = function(fileName) {
window.location.href = 'logreport/downLoadFile?fileName=asdad1';
};
I didn't have enough credit to give a comment so wiritting here.. Thanks user1298426. I was strugling like anything for this. I was trying with AJAX. With window.location.href, I can download file in browser...
MY javascript code is as follows:
jQuery('#exportToZip').click(function() {
window.location.href = '*****';
});
*****: is the url mapping that I have in controller.
#RequestMapping(value = "/****")
#ResponseBody
public void downloadRequesthandler(HttpServletRequest request,HttpServletResponse response) {
String status;
try {
filedownloader.doGet(request, response);
} catch (ServletException e) {
status="servlet Exception occured";
e.printStackTrace();
} catch (IOException e) {
status="IO Exception occured";
e.printStackTrace();
}
//return status;
}
public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
ServletContext context = request.getServletContext();
// construct the complete absolute path of the file
File downloadFile = new File(filePath);
System.out.println("downloadFile path: "+ filePath);
FileInputStream inputStream = new FileInputStream(downloadFile);
// get MIME type of the file
String mimeType = context.getMimeType(fullPath);
if (mimeType == null) {
// set to binary type if MIME mapping not found
mimeType = "application/octet-stream";
}
System.out.println("MIME type: " + mimeType);
response.setContentLength((int) downloadFile.length());
// set headers for the response
String headerKey = "Content-Disposition";
String headerValue = String.format("attachment; filename=\"%s\"",downloadFile.getName());
response.setHeader(headerKey, headerValue);
OutputStream outStream = response.getOutputStream();
byte[] buffer = new byte[BUFFER_SIZE];
System.out.println("buffer: "+ buffer.length);
int bytesRead = -1;
// write bytes read from the input stream into the output stream
//be carefull in this step. "writebeyondcontentlength" and "response already committed" error is very common here
while ((bytesRead = inputStream.read(buffer))!=-1 ) {
outStream.write(buffer, 0, bytesRead);
}
inputStream.close();
outStream.close();
}
Trying to download file with ajax is a blunder....
cheers......
Instead of using IOUtils copy method
ServletOutputStream out = response.getOutputStream();
IOUtils.copy(in, out);
You can use following :
ServletOutputStream out = response.getOutputStream();
byte[] bytes = IOUtils.toByteArray(in);
out.write(bytes);
out.close();
out.flush();
Hope this will work.

file download pop up is not coming

Wrote a simple code to download a file from file system but still not getting download pop up hence file is not downloading ,not even throwing any error .Please help me out.Following is my code written on controller side.
#RequestMapping(value = "download", method=RequestMethod.POST)
public #ResponseBody void download(HttpServletRequest request, HttpServletResponse response){
String fileName="/home/test/Testing.xlsx";
PrintWriter out=null;
try{
System.out.println(fileName.substring(fileName.lastIndexOf('/')+1)+"fileName");
response.setContentType("application/vnd.ms-excel");
response.setHeader("Cache-Control", "must-revalidate");
response.setHeader( "Pragma", "public" );
response.setHeader("Content-Disposition", "attachment; filename=" + fileName.substring(fileName.lastIndexOf('/')+1) );
out = response.getWriter();
int i;
FileInputStream inputStream = new FileInputStream(fileName);
while ((i = inputStream.read()) != -1) {
out.write(i);
}
inputStream.close();
out.close();
}
catch(Exception e){
System.out.println(e);
}
}
here mistake was POST method, we should not use post method instead we should always use GET method while writing program for download.
#RequestMapping(value = "download", method=RequestMethod.GET)
public #ResponseBody void download(HttpServletRequest request, HttpServletResponse response){
String fileName="/home/test/Testing.xlsx";
PrintWriter out=null;
try{
System.out.println(fileName.substring(fileName.lastIndexOf('/')+1)+"fileName");
response.setContentType("application/vnd.ms-excel");
response.setHeader("Cache-Control", "must-revalidate");
response.setHeader( "Pragma", "public" );
response.setHeader("Content-Disposition", "attachment; filename=" + fileName.substring(fileName.lastIndexOf('/')+1) );
out = response.getWriter();
int i;
FileInputStream inputStream = new FileInputStream(fileName);
while ((i = inputStream.read()) != -1) {
out.write(i);
}
inputStream.close();
out.close();
}
catch(Exception e){
System.out.println(e);
}
}

Downloaded File Size 0

I'm trying here to add a specific dialog bean for action on Alfresco Explorer that supposed to download a specific docx file. The code is working fine when I hit the download action, it downloads the file but as mentioned in my question title, the file size is 0 bytes.
I'm using this to do that:
public class NewFormDialog extends BaseDialogBean {
protected String aspect;
protected String finishImpl(FacesContext context, String outcome)
throws Exception {
download(aspect);
// // get the space the action will apply to
// NodeRef nodeRef = this.browseBean.getActionSpace().getNodeRef();
//
// // resolve the fully qualified aspect name
// QName aspectToAdd = Repository.resolveToQName(this.aspect);
//
// // add the aspect to the space
// getNodeService().addAspect(nodeRef, aspectToAdd, null);
//
// // return the default outcome
return outcome;
}
public boolean getFinishButtonDisabled() {
return false;
}
public String getFinishButtonLabel() {
return "Download";
}
public void download(String pAspect) throws ServletException, IOException {
String filename = pAspect;
String filepath = "\\";
BufferedInputStream buf = null;
ServletOutputStream myOut = null;
try {
FacesContext fc = FacesContext.getCurrentInstance();
HttpServletResponse response = (HttpServletResponse) fc
.getExternalContext().getResponse();
myOut = response.getOutputStream();
File myfile = new File(filepath + filename);
// set response headers
response.setContentType("application/octet-stream");
response.addHeader("Content-Disposition", "attachment; filename="
+ filename);
response.setContentLength((int) myfile.length());
FileInputStream input = new FileInputStream(myfile);
buf = new BufferedInputStream(input);
int readBytes = 0;
// read from the file; write to the ServletOutputStream
while ((readBytes = buf.read()) != -1)
myOut.write(readBytes);
myOut.flush();
response.flushBuffer();
} catch (IOException ioe) {
throw new ServletException(ioe.getMessage());
} finally {
// close the input/output streams
if (myOut != null)
myOut.close();
if (buf != null)
buf.close();
FacesContext.getCurrentInstance().responseComplete();
}
}
public String getAspect() {
return aspect;
}
public void setAspect(String aspect) {
this.aspect = aspect;
}
}
I tried every solution that I found by none works.
Thank you in advance.
The File.length() method returns 0 if the file does not exist. Check to make sure that the file exists.
Tip: The Apache Commons IO library simplifies many I/O related tasks. For example, the following code snippet streams the contents of a file to the servlet response:
HttpServletResponse response = ...
File myfile = ...
InputStream in = null;
OutputStream out = null;
try {
in = new FileInputStream(myfile);
out = response.getOutputStream();
IOUtils.copy(in, out);
} finally {
IOUtils.closeQuietly(in); //checks for null
IOUtils.closeQuietly(out); //checks for null
}

Categories