I am writing a REST webserivce using spring. I have to return back a file in the response.
Its a GET call and when the user enters the URL, the user should be shown with the download section in the browser.
I am not sure what should be the return type in the controller. Do i have to specify any content type i code?
I had the similar requirement in my project. I used the below piece of code
@Controller
@RequestMapping("/reports")
public class ReportsController {
protected static String PRODUCTIVITY_REPORT_FILE = "productivityReportFile";
@Resource(name="propertyMap")
protected Map<String, String> propertyMap;
@RequestMapping(value="/cratl/productivity_report", method=RequestMethod.GET, produces="application/vnd.openxmlformats-officedocument.spreadsheetml.sheet")
public @ResponseBody byte[] getProductivityReport()
throws Exception {
byte[] reportBytes = null;
try {
File reportFile = new File(propertyMap.get(PRODUCTIVITY_REPORT_FILE));
if (reportFile != null && reportFile.exists()) {
InputStream reportInputStream = new FileInputStream(reportFile);
long length = reportFile.length();
reportBytes = new byte[(int)length];
int offset = 0;
int numRead = 0;
while (offset < reportBytes.length
&& (numRead = reportInputStream.read(reportBytes, offset, reportBytes.length-offset)) >= 0) {
offset += numRead;
}
if (offset < reportBytes.length) {
throw new Exception("Could not completely read file "+ reportFile.getName());
}
reportInputStream.close();
}
} catch (Exception e) {
e.printStackTrace();
}
return reportBytes;
}
I hope it helps you
Your controller method, which can have any name you want, returns a String with a url name that is defined in the views.xml that is defined for the view you want to load, the downloads section in this case. So your controller looks like this:
@Controller
public class MyController {
@RequestMapping(value = "/downloads", method = RequestMethod.GET)
public String getDownloadSection() {
System.out.println("getting downloads");
return "downloads/index";
}
}
Your views.xml should contain the tag:
<definition extends="default" name="downloads/index">
<put-attribute name="body" value="/WEB-INF/views/downloads/index.jspx"/>
</definition>
The extends="default" is a tile definition that should be in your layouts.xml
I think thats about it. If you do a GET request to //yoursite/downloads it should print the message.
That should answer your question i hope :)
I used the below piece of code
FileInputStream inputStream = new FileInputStream("FileInputStreamDemo.java"); //read the file
response.setHeader("Content-Disposition","attachment; filename=test.txt");
try {
int c;
while ((c = inputStream.read()) != -1) {
response.getWriter().write(c);
}
} finally {
if (inputStream != null)
inputStream.close();
response.getWriter().close();
}
This was found in one more thread
how to write a file object on server response and without saving file on server?
