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Getting 404 for HttpURLConnection

I have a service deployed in Heroku that produces a pdf file output. When I hit the URL in the browser, I am able to download the pdf file (I am not prompting to save (as per my requirement), it auto save to defined path in the code). So service is up and available. But when I am accessing it using HttpURLConnection I am getting 404 error. . Could anyone help me out on this?
Following is the link I am accessing:
http://quiet-savannah-7144.herokuapp.com/services/time/temp
Here is the service code, deployed in Heroku server:
#jawax.ws.rs.core.Context
ServletContext context;
#GET
#path("/temp")
#Produces("application/pdf")
public Response getPdf() throws IOException{
InputStream is = context.getResourceAsStream("/static/temp.pdf");
ResponseBuilder res = Response.ok(is);
res.header("Content-Disposition","attachment; filename=temp.pdf");
return res.build();
}
Note: I have my file in the location webapp/static/temp.pdf
Client code is as follows:
try {
URL url = new URL("http://quiet-savannah-7144.herokuapp.com/sevices/time/temp");
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setDoOutput(true);
conn.setRequestMethod("GET");
conn.setRequestProperty("Content-Type", "application/json");
int code = conn.getResponseCode();
System.out.println("code>>"+code+"<<");
if (conn.getResponseCode() == 200) {
System.out.println("*************************done****************************");
InputStream inputStream = conn.getInputStream();
OutputStream output = new FileOutputStream("D:/copyOfTest.pdf");
byte[] buffer = new byte[1024];
int bytesRead;
while ((bytesRead = inputStream.read(buffer)) != -1) {
output.write(buffer, 0, bytesRead);
}
output.close();
} else {
Scanner scanner = new Scanner(conn.getErrorStream());
while(scanner.hasNext())
System.out.println(scanner.next());
scanner.close();
}
conn.disconnect();
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
I tried content type with pdf and x-pdf as shown below, nothing is working
conn.setRequestProperty("Content-Type", "application/pdf");
conn.setRequestProperty("Content-Type", "application/x-pdf");
When I deploy the service locally in Tomcat server in my machine, then things are absolutely fine. I am struggling from the past 6 hours to resolve this, but no clue. Actually I have to fetch it in the android AsyncTask. If I am able to do it in java, then I could achieve the same in android. Could someone help me out on this.
Thanks in advance

I see a few problems.
First, if you do a GET you should not write conn.setDoOutput(true); cause you're not outputting from your application to the server.
Second, the Content-Type header is the content-type of what YOU send to the server, not the opposite, so since you're not sending anything but just doing a get, you should not set it.
Instead, maybe, if you want, you can set the Accept header.

Content-Type is a server header. You should send an Accept header, maybe you could try something generic like Accept: *.

Though this thread is old, may be useful for some:
Came up with similar problem and solved by adding the "Accept-Encoding: gzip, deflate, br" header

How to Pass a File through an HttpURLConnection

I'm trying to get an image hosting on our server available to be displayed on a client. As per the specs of the project:
"When a Client receives such a URL, it must download the
contents (i.e., bytes) of the file referenced by the URL.
Before the Client can display the image to the user, it must first retrieve (i.e., download) the bytes of the
image file from the Server. Similarly, if the Client receives the URL of a known data file or a field help file
from the Server, it must download the content of those files before it can use them."
I'm pretty sure we have the server side stuff down, because if I put the url into a browser it retrieves and displays just fine. So it must be something with the ClientCommunicator class; can you take a look at my code and tell me what the problem is? I've spent hours on this.
Here is the code:
Where I actually call the function to get and display the file: (This part is working properly insofar as it is passing the right information to the server)
JFrame f = new JFrame();
JButton b = (JButton)e.getSource();
ImageIcon image = new ImageIcon(ClientCommunicator.DownloadFile(HOST, PORT, b.getLabel()));
JLabel l = new JLabel(image);
f.add(l);
f.pack();
f.setVisible(true);
From the ClientCommunicator class:
public static byte[] DownloadFile(String hostname, String port, String url){
String image = HttpClientHelper.doGetRequest("http://"+hostname+":"+port+"/"+url, null);
return image.getBytes();
}
The pertinent httpHelper:
public static String doGetRequest(String urlString,Map<String,String> headers){
URL url;
HttpURLConnection connection = null;
try {
//Create connection
url = new URL(urlString);
connection = (HttpURLConnection)url.openConnection();
connection.setRequestMethod("GET");
connection.setRequestProperty("Content-Language", "en-US");
connection.setUseCaches (false);
connection.setDoInput(true);
connection.setDoOutput(true);
if(connection.getResponseCode() == 500){
return "failed";
}
//Get Response
InputStream is = connection.getInputStream();
BufferedReader rd = new BufferedReader(new InputStreamReader(is));
String line;
StringBuffer response = new StringBuffer();
while((line = rd.readLine()) != null) {
response.append(line);
}
rd.close();
return response.toString();
} catch (Exception e) {
e.printStackTrace();
return null;
} finally {
if(connection != null) {
connection.disconnect();
}
}
}
After that, it jumps into the server stuff, which as I stated I believe is working correctly because clients such as Chrome can retrieve the file and display it properly. The problem has to be somewhere in here.
I believe that it has to do with the way the bytes are converted into a string and then back, but I do not know how to solve this problem. I've looked at similar problems on StackOverflow and have been unable to apply them to my situation. Any pointers in the right direction would be greatly appreciated.

If your server is sending binary data, you do not want to use an InputStreamReader, or in fact a Reader of any sort. As the Java API indicates, Readers are for reading streams of characters (not bytes) http://docs.oracle.com/javase/7/docs/api/java/io/Reader.html, which means you will run into all sorts of encoding issues.
See this other stack overflow answer for how to read bytes from a stream:
Convert InputStream to byte array in Java

Do your homework.
Isolate the issue. Modify the server side to send only 256 all possible bytes. Do a binary search and reduce it to small set of bytes.
Use http proxy tools to monitor the bytes as they are transmitted. Fiddler in windows world. Find other ones for the *nix environments.
Then see where the problem is happening and google/bing the suspicions or share the result.

Java Applet hangs in IE when getting HttpUrlConnection outputstream

I have a signed file uploader applet that works in Chrome but seems to hang when run in IE. In IE, I can successfully upload a file (or set of files) one time but the next time I try to upload another file, the browser freezes and I have to close the browser. It seems to be happening when I attempt to retrieve the outputstream of the HttpUrlConnection object. Here is my code:
public void upload(URL url, URL returnUrl, List<FileIconPanel> files) {
HttpURLConnection conn = null;
try {
conn = (HttpURLConnection) url.openConnection();
conn.setDoOutput(true);
conn.setDoInput(true);
conn.setUseCaches(false);
conn.setChunkedStreamingMode(1024);
HttpURLConnection.setFollowRedirects(false);
conn.setRequestProperty("content-type", "application/zip");
conn.setRequestMethod("POST");
//This zip output stream will server as our stream to the server and will zip each file while
// it sends it to the server.
ZipOutputStream out = new ZipOutputStream(conn.getOutputStream());
for (int i = 0; i < files.size(); i++) {
//For each file we will create a new entry in the ZIP archive and stream the file into that entry.
File f = (File) files.get(i).getFile();
ZipEntry entry = new ZipEntry(f.getName());
out.putNextEntry(entry);
InputStream in = new FileInputStream(f);
int read;
byte[] buf = new byte[1024];
while ((read = in.read(buf)) > 0) {
out.write(buf, 0, read);
}
out.closeEntry();
}
//Once we are done writing out our stream we will finish building the archive and close the stream.
out.finish();
out.close();
// Now that we have set all the connection parameters and prepared all
// the data we are ready to connect to the server.
conn.connect();
// read & parse the response
InputStream is = conn.getInputStream();
StringBuilder response = new StringBuilder();
byte[] respBuffer = new byte[4096];
while (is.read(respBuffer) >= 0) {
response.append(new String(respBuffer).trim());
}
is.close();
} catch (IOException ioE) {
ioE.printStackTrace();
logger.info("An unexpected exception has occurred. Contact your system administrator");
} catch (Exception e) {
e.printStackTrace();
logger.info("An unexpected exception has occurred. Contact your system administrator");
} finally {
//Once we are done we want to make sure to disconnect from the server.
if (conn != null) conn.disconnect();
}
}
I can see in the log files that it is freezing a this line:
ZipOutputStream out = new ZipOutputStream(conn.getOutputStream());
the second time I try to upload a file. This code also does work in IE under java 6. It has had this problem since I updated to the latest.
Is there something I'm leaving open that I need to make sure to close out before using the applet again? Been beating my head against this for the last two days. Sure hope someone can help...

I have an idea of what's going on but I don't know exactly the details of the what's causing the problem. I at least figured it out a workaround...I was using a jquery dialog box to display the applet. I was doing this on the fly so every time I open the dialog box, it was building the applet again. It's strange because I was in fact removing the div element that contained the applet every time the dialog box was closed so I would have thought that would ensure the old applet instance was destroyed as well. Chrome seems to be smart enough to destroy it and create a new one (or something to that effect) but IE has problems.

TCP connection is not reused for HTTP requests with HttpURLConnection

I'm have created an application which sends GET requests to a URL, and then downloads the full content of that page.
The client sends a GET to e.g. stackoverflow.com, and forwards the response to a parser, which has the resposibility to find all the sources from the page that needs to be downloaded with subsequent GET requests.
The method below is used to send those GET requests. It is called many times consecutively, with the URLs returned by the parser. Most of those URLs are located on the same host, and should be able to share the TCP connection.
public static void sendGetRequestToSubObject(String RecUrl)
{
URL url = new URL(recUrl.toString());
URLConnection connection = url.openConnection ();
InputStreamReader isr = new InputStreamReader(connection.getInputStream());
}
Each time this method is called, a new TCP connection is created (with a TCP 3-way handshake) and the GET is then sent on that connection. But I want to reuse the TCP connections, to improve performance.
I guess that since I create a new URL object each time the method is called, this is the way it going to work...
Maybe someone can help me do this in a better way?
Thanks!

HttpURLConnection will reuse connections if it can!
For this to work, several preconditions need to be fulfilled, mostly on the server side. Those preconditions are described in the article linked to above.

Found the problem! I was not reading the input stream properly. This caused the input stream objects to hang, and they could not be reused.
I only defined it, like this:
InputStreamReader isr = new InputStreamReader(connection.getInputStream());
but I never read from it :-)
I changed the read method as well. Instead of a buffered reader I stole this:
InputStream in = null;
String queryResult = "";
try {
URL url = new URL(archiveQuery);
HttpURLConnection urlConn = (HttpURLConnection) url.openConnection();
HttpURLConnection httpConn = (HttpURLConnection) urlConn;
httpConn.setAllowUserInteraction(false);
httpConn.connect();
in = httpConn.getInputStream();
BufferedInputStream bis = new BufferedInputStream(in);
ByteArrayBuffer baf = new ByteArrayBuffer(50);
int read = 0;
int bufSize = 512;
byte[] buffer = new byte[bufSize];
while(true){
read = bis.read(buffer);
if(read==-1){
break;
}
baf.append(buffer, 0, read);
}
queryResult = new String(baf.toByteArray());
} catch (MalformedURLException e) {
// DEBUG
Log.e("DEBUG: ", e.toString());
} catch (IOException e) {
// DEBUG
Log.e("DEBUG: ", e.toString());
}
}
From here: Reading HttpURLConnection InputStream - manual buffer or BufferedInputStream?

HttpsURLConnection Connection Problems

I'm a problem with a HttpsURLConnection that I can't seem to solve. Basically, I'm sending up some info to a server and if some of that data is wrong, the server sends me a 500 response code. However, it also sends a message in the response telling me which bit of data was wrong. The problem is that the message is always empty when I read it in. I think this is because a filenotfound exception always gets thrown before the stream can be read. Am I right? I tried reading the errorstream as well but this is always empty. Here's a snippet:
conn = (HttpsURLConnection) connectURL.openConnection();
conn.setDoOutput(true);
conn.setConnectTimeout(30000);
conn.setReadTimeout(30000);
conn.setRequestMethod("POST");
conn.setRequestProperty("Content-Length",
Integer.toString(outString.getBytes().length));
DataOutputStream wr = new DataOutputStream(conn
.getOutputStream());
wr.write(outString.getBytes());
wr.flush();
wr.close();
if(conn.getResponseCode>400{
String response = getErrorResponse(conn);
public String getErrorResponse(HttpsURLConnection conn) {
Log.i(TAG, "in getResponse");
InputStream is = null;
try {
//is = conn.getInputStream();
is = conn.getErrorStream();
// scoop up the reply from the server
int ch;
StringBuffer sb = new StringBuffer();
while ((ch = is.read()) != -1) {
sb.append((char) ch);
}
//System.out.println(sb.toString());
return sb.toString();
// return conferenceId;
}
catch (Exception e){
e.printStackTrace();
}
}

So just to follow up on this, here is how I solved it:
public static String getResponse(HttpsURLConnection conn) {
Log.i(TAG, "in getResponse");
InputStream is = null;
try {
if(conn.getResponseCode()>=400){
is = conn.getErrorStream();
}
else{
is=conn.getInputStream();
}
...read stream...
}
It seems that calling them like this produced an error stream with a message. Thanks for the suggestions!

Try setting content-type request property to "application/x-www-form-urlencoded"
The same is mentioned on this link:
http://developers.sun.com/mobility/midp/ttips/HTTPPost/
The Content-Length and Content-Type headers are critical because they tell the web server how many bytes of data to expect, and what kind, identified by a MIME type.
In MIDP clients the two most popular MIME types are application/octet-stream, to send raw binary data, and application/x-www-form-urlencoded, to send name-value pairs

Are you in control of the server? In other words, did you write the process that runs on the server and listens to the port you're trying to access?
If you did, then you should also be able to debug it and see why your process returns 404.
If you didn't, then describe your architecture (HTTP server, the component it invokes to respond to your HTTP(S) request, etc) and we'll take it from there.
In the very simplest case, of an HTTP server being an Apache server yielding control to some PHP script, it means that Apache couldn't assign your request to anything. Most likely a Web server misconfiguration. Provide some more details and we'll help you out.