Develop Reference

Java Client code to call restful web service

Can anybody tell me how to write a java client code to call restful web service with one parameter say email? I am trying the below code. But I am getting response as Success. Once this is success, I need the below XPHONE value. How to get this value?
XPHONE: 52-33-3669-7000
Here is the client code:
URL url = new URL("http://bluepages.ibm.com/BpHttpApisv3/wsapi?byInternetAddr=user.email");
HttpURLConnection conn = (HttpURLConnection) url
.openConnection();
conn.setRequestMethod("GET");
conn.setReadTimeout(15000);
conn.setConnectTimeout(15000);
conn.setRequestProperty("Accept",
"application/json");
conn.connect();

I think you just missing response body handling.
There is nice article about rest-client code: article.

You can try using the JavaLite Http client:
JavaLite Http

Depends on how API is implemented value can be in response body or even in header, so this info you should know from specification or ask in dev team.
First try to check if everything works fine using CURL or better "Advanced rest client" ( its extension in Chrome browser) if it works, than just transfer flow to your code. How to use advanced rest client look here

How to display MJPEG-stream in Vaadin (Java)?

I`m looking for a way to display a MJPEG-stream (from ip cam) in my vaadin application.
My problem is the necessary authentication to start the stream.
Really easy solution to simply get the stream:
String url = "...urlgoeshere/video.mjpg";
Image image = new Image();
image.setSource(new ExternalResource(url));
content.addComponent(image);
It works like a charm if I allow anonymous connections to the camera, but thats not really my goal.
I tried to authenticate with:
Authenticator.setDefault(new MyAuthenticator(username, password));
but it doesn`t affect the request.
If I manually set up a request like:
String url = "...urlgoeshere/video.mjpg";
Authenticator.setDefault(new MyAuthenticator("username", "password"));
URL obj = new URL(url);
HttpURLConnection con = (HttpURLConnection) obj.openConnection();
con.setRequestMethod("GET");
the authentication works, but this way I have to handle all the images by myself.
Are there any better ways to display a stream which requires authentication?

I think you should be able to use the username & password in the URL of the external resource.
https://foo:password#example.com
But this depends on the protocol the webcam uses for authentification,
and you will also have the username and password "visible" in the
html / javascript of your application.
And one more note:
Microsoft did disable this some time ago, so if your users are using IE,
this won't work.

How to pass input to a web page using a automated script

How to pass input to a php web page using a automated script ,i.e. i just want to know how pass arguments to text fields using a script. like passing input to username and password field of a web page and then pressing submit button(that too with a script).
favorable language: JAVA

Try Selenium. Selenium is great at automating web browsers.
http://seleniumhq.org/
Also has pure support with Java. But not only.
When it comes to custom methods, see ...
String urlParameters = "param1=a&param2=b&param3=c";
String request = "http://example.com/index.php";
URL url = new URL(request);
HttpURLConnection connection = (HttpURLConnection) url.openConnection();
connection.setDoOutput(true);
connection.setDoInput(true);
connection.setInstanceFollowRedirects(false);
connection.setRequestMethod("POST");
connection.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");
connection.setRequestProperty("charset", "utf-8");
connection.setRequestProperty("Content-Length", "" + Integer.toString(urlParameters.getBytes().length));
connection.setUseCaches (false);
DataOutputStream wr = new DataOutputStream(connection.getOutputStream ());
wr.writeBytes(urlParameters);
wr.flush();
wr.close();
connection.disconnect();
source (Java - sending HTTP parameters via POST method easily)

if you web page uses the GET method to accept data (i.e. from URL), just connect to the web pages giving the data you want to pass:
http://www.mysite.com/mypage.html?data0=data0,data1=data1
if the web page uses POST things get a little bit more complicated: you have to forge an appropriate HTML request with all your data in the header (as POST method requires)

You can use the Apache HTTPClient - see the example at:
http://hc.apache.org/httpclient-3.x/methods/post.html
This allows you to simulate submitting a fully filled form directly to the destination page and grab the results.
Remember that, after the call, you have to grab and store the session cookie in the response and resubmit it to the following pages you want to "visit" to stay "logged on"

I would like to show how I would do to pass an input to the HTML. I usually use python to send request to the page where I need to input the data. Before doing that you need to know if you need to supply web-cookies or not, if yes, copy the cookie, if you need to be logged in otherwise not, just check that. Once that is done, you need to know the field names for the input area as you will be using them to POST or GET data using your script. Here is sample usage.
import urllib
import urllib2
import string
headers = {'Cookie': 'You cookies if you need'}
values = {'form_name':'sample text', 'submit':''}
data = urllib.urlencode(values)
req = urllib2.Request('website where you making request to',data,headers)
opener1 = urllib2.build_opener()
page1=opener1.open(req)
#OPTIONAL
htmlfile=page1.read()
fout = open('MYHTMLFILE.html', "wb")
fout.write(htmlfile)
fout.close()

Getting HTTP response code in Java

I need to find the HTTP response code of URLs in java. I know this can be done using URL & HTTPURLConnection API and have gone through previous questions like this
and this.
I need to do this on around 2000 links so speed is the most required attribute and among those I already have crawled 150-250 pages using crawler4j and don't know a way to get code from this library (due to which I will have to make connection on those links again with another library to find the response code).

In Crawler4J, the class WebCrawler has a method handlePageStatusCode, which is exactly what you are looking for and what you would also have found if you had looked for it. Override it and be happy.

The answer behind your first link contains everything you need:
How to get HTTP response code for a URL in Java?
URL url = new URL("http://google.com");
HttpURLConnection connection = (HttpURLConnection)url.openConnection();
connection.setRequestMethod("GET");
connection.connect();
int code = connection.getResponseCode();
The response code is the HTTP code returned by the server.

Trying to GET a Google Spreadsheet in Java is returning HTTP error 405

Been working on this all day and have gotten no where with it.
My Java code looks like this:
final URL url = new URL(String.format("https://spreadsheets.google.com/feeds/download/spreadsheets/Export?key=%s&exportFormat=tsv&gid=0", spreadsheetId));
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setRequestProperty("Authorization", "GoogleLogin auth=" + wiseAuth.getAuthToken());
conn.setRequestProperty("GData-Version", "3.0");
conn.setRequestMethod("GET");
conn.setDoOutput(true); // trouble here, see below
conn.setInstanceFollowRedirects(true);
conn.connect();
I always get a FileNotFound error when attempting to do conn.getInputStream(). I narrowed it down to being that the response code is 405 Method Not Allowed. The exception is returning me my URL and I can access the page just fine in my browser.
It was then that I discovered that setDoOutput(true) executes a POST internally. But if I remove that line, conn.getInputStream() is null, and conn.getOutputStream() appears to return nothing--though maybe I am setting it up wrong?

I don't recommend you to do it like this, even if you get it working now you cannot ensure you will get it working in the future if Google started changing it.
Instead, consider using Google Spreadsheet API. The provided Java examples are pretty straightforward and you should able to accomplish what you want.

I would recommend using a web debugger like Fiddler to see what exactly your application is sending in the GET request and compare it to your browser. You might be missing an important header or something, and Fiddler makes it really easy to slowly strip down your browser's request to the essential elements (just drag a request to clone it, then take out headers).