Receive image file through rest Api - java

How to receive an image file through Rest APIs. There is an option of MULTIPART_FORM_DATA which looks like it will send files in parts as in more than one request.
I want to receive images very fast on server. around 2 images per second.

Simply read image in a File and use Response class to build the response.
Response.ok(new File("myimage.jpg"), "image/jpeg").build();
There are other variations of the same.
Read the image using following.
URL url = new URL("http://localhost:8080/myimage/1");
URLConnection connection = url.openConnection();
input = connection.getInputStream();
byte[] buffer = new byte[1024];
int n = - 1;
OutputStream fos = new FileOutputStream("Output.jpg" );
while ( (n = input.read(buffer)) != -1)
{
fos.write(buffer, 0, n);
}
fos.close();
You can use Apache HTTP client to make it prettier.

Related

How to upload AppendBlob/a file larger than the 4mb limit into Azure Storage/Blob in Java?

How to upload a large(>4mb) file as an AppendBlob using Azure Storage Blob client library for Java?
I've successfully implemented the BlockBlob uploading with large files and it seems that the library internally handles the 4mb(?) limitation for single request and chunks the file into multiple requests.
Yet it seems that the library is not capable of doing the same for AppendBlob, so how can this chunking be done manually? Basically I think this requires to chunk an InputStream into smaller batches...
Using Azure Java SDK 12.14.1
Inspired by below answer in SO (related on doing this in C#):
c-sharp-azure-appendblob-appendblock-adding-a-file-larger-than-the-4mb-limit
... I ended up doing it like this in Java:
AppendBlobRequestConditions appendBlobRequestConditions = new AppendBlobRequestConditions()
.setLeaseId("myLeaseId");
try (InputStream input = new BufferedInputStream(
new FileInputStream(file));) {
byte[] buf = new byte[AppendBlobClient.MAX_APPEND_BLOCK_BYTES];
int bytesRead;
while ((bytesRead = input.read(buf)) > 0) {
if (bytesRead != buf.length) {
byte[] smallerData = new byte[bytesRead];
smallerData = Arrays.copyOf(buf, bytesRead);
buf = smallerData;
}
try (InputStream byteStream = new ByteArrayInputStream(buf);) {
appendBlobClient
.appendBlockWithResponse(byteStream, bytesRead,
null, appendBlobRequestConditions, null,
null);
}
}
}
Of course you need to do bunch of stuff before this, like make sure the AppendBlob exists, and if not then create it before trying to append any data.

WebResourceResponse can't read full inputstream from HttpConnection (Android)

I'm working with an ionic application(like hybrid) which can play some videos.I want to add some headers to the request so that I override the "shouldInterceptRequest".
URL myUrl = new URL(real);
HttpURLConnection connection = (HttpURLConnection) myUrl.openConnection();
for (Map.Entry < String, String > entry: headers.entrySet()) {
connection.setRequestProperty(entry.getKey(), entry.getValue());
}
InputStream in = connection.getInputStream();
WebResourceResponse response = new WebResourceResponse("video/mp4", "UTF-8", in );
for (Map.Entry < String, List < String >> entry: connection.getHeaderFields().entrySet()) {
resHeaders.put(entry.getKey(), entry.getValue().get(0));
}
This code can't work.The video tag in html can't play the video.
So I add some code.
byte[] bytes = new byte[30 * 1024 * 1024];
ByteArrayOutputStream byteBuffer = new ByteArrayOutputStream();
int len = 0;
while ((len = in.read(bytes)) != -1) {
byteBuffer.write(bytes, 0, len);
}
bytes = byteBuffer.toByteArray();
WebResourceResponse response = new WebResourceResponse("video/mp4", "UTF-8", new ByteArrayInputStream(bytes));
When I read inputstream into bytes and send bytes to WebResourceResponse, the video can be play.However it means my application will use lots of memory if the video is large.
So that, I want to know is there any way to play the video without saving inputstream into bytes.
OK.Fianlly,I found my way.
Actually, my goal is to add custom headers to resource request and now I found there is an easier way to do it.
For example, if I want to load a image,I will use img tag like this,<img src="the_url_of_image">,and I can't add any header to the request unless I interecept the request.
However,we can use blob now.We can request the resource by using something like ajax and use createObjectURL to create a url links to the resource.

how to get file from this url , using java code?

To use google translate api I figured out this url
http://translate.google.com/translate_a/t?client=t&text=revenge&hl=en&sl=en&tl=hi&ie=UTF-8&oe=UTF-8&multires=1&otf=1&ssel=3&tsel=3&sc=1
If you click on it you will get a file in json format with accurate translation.
To retrieve this file using java program I wrote following code.
String word = "revenge";
System.setProperty("http.proxyHost", "172.30.0.16");
System.setProperty("http.proxyPort", "3128");
URL url = new URL("http://translate.google.com/translate_a/t?client=t&text="+word+"&hl=en&sl=en&tl=hi&ie=UTF-8&oe=UTF-8&multires=1&otf=1&ssel=3&tsel=3&sc=1");
url.openConnection();
InputStream reader = url.openStream();
FileOutputStream writer = new FileOutputStream("t");
byte[] buffer = new byte[153600];
int bytesRead = 0;
while ((bytesRead = reader.read(buffer)) > 0)
{
writer.write(buffer, 0, bytesRead);
buffer = new byte[153600];
}
writer.close();
reader.close();
But it shows following error
Exception in thread "main" java.io.IOException: Server returned HTTP response code: 403 for URL: http://translate.google.com/translate_a/t?client=t&text=Moon&hl=en&sl=en&tl=hi&ie=UTF-8&oe=UTF-8&multires=1&otf=1&ssel=3&tsel=3&sc=1
at sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1403)
at java.net.URL.openStream(URL.java:1029)
at smsMain.main(smsMain.java:20
Hope to get some help. Because we are getting file manually but using program it is forbidden.
From Google Translate home page:
Google Translate API is available as a paid service. See the Pricing
and FAQ pages for details.
So getting an error is not really surprising.

android tcp client file receive

I am trying to send a file (png to be specific) over sockets from python server to android client. I know that my python server is sending the data, I just can't figure out how to receive the data on the android side. Here is what the code looks like to receive the file.
String path = Environment.getExternalStorageDirectory().toString() +"/tmp/test.png";
try {
socket = new Socket("192.168.1.129", 29877);
is = socket.getInputStream();
out = new FileOutputStream(path);
byte[] temp = new byte[1024];
for(int c = is.read(temp,0,1024); c > 0; c = is.read(temp,0,1024)){
out.write(temp,0,c);
Log.d("debug tag", out.toString());
}
Log.d("debug tag", temp.toString());
Bitmap myBitmap = BitmapFactory.decodeByteArray(temp, 0, temp.length);
imageView.setImageBitmap(myBitmap);
Thanks for any advice.
You are reading from socket in 1K chunks and saving them into a file. Then you try to interpret the last chunk as a bitmap. This doesn't work.
Either read your image from the file after you saved it, or buffer it all in memory.

Parsing PDF files hosted in web servers

I have used iText to parse pdf files. It works well on local files but I want to parse pdf files which are hosted in web servers like this one:
"http://protege.stanford.edu/publications/ontology_development/ontology101.pdf"
but I don't know how??? Could you please answer me how to do this task using iText or other libraries... thx
You need to download the bytes of the PDF file. You can do this with:
URL url = new URL("http://.....");
URLConnection conn = url.getConnection();
if (conn.getResponseCode() != HttpURLConnection.HTTP_OK) { ..error.. }
if ( ! conn.getContentType().equals("application/pdf")) { ..error.. }
InputStream byteStream = conn.getInputStream();
try {
... // give bytes from byteStream to iText
} finally { byteStream.close(); }
Use the URLConnection class:
URL reqURL = new URL("http://www.mysite.edu/mydoc.pdf" );
URLConnection urlCon = reqURL.openConnection();
Then you can use the URLConnection method to retrieve the content. Easiest way:
InputStream is = urlCon.getInputStream();
byte[] b = new byte[1024]; //size of a buffer, can be any
int len;
while((len = is.read(b)) != -1){
//Store the content in preferred way
}
is.close();
Nothing to it. You can pass a URL directly into PdfReader, and let it handle the streaming for you:
URL url = new URL("http://protege.stanford.edu/publications/ontology_development/ontology101.pdf" );
PdfReader reader = new PDFReader( url );
The JavaDoc is your friend.

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