I am little confused with the below code or behavior of HttpURLConnection class. I have the below code which hits the URL (rest service in .net) and gets the response from it. When I run the code I am getting the response in both Windows and Unix environment. I have access to this URL.
When I provided the same code to someone who don't have access to the URL, it throws 401 Unauthorized error. But in below code I didn't pass my credentials, how does it automatically validates my credentials ? Is it working for me because HttpURLConnection sets Windows authentication in background in request ?
URL url = new URL(URL);
HttpURLConnection connection = (HttpURLConnection) url.openConnection();
connection.setRequestMethod("GET");
connection.setUseCaches(false);
connection.setDoOutput(true);
BufferedReader in = new BufferedReader( new InputStreamReader(connection.getInputStream()));
String inputLine;
StringBuffer response = new StringBuffer();
while ((inputLine = in.readLine()) != null) {
response.append(inputLine);
}
in.close();
System.out.println(response);
Related
I am opening an HttpURLConnection and with POST method, I am sending a JSON request that I build form another class. The JSON is structured correctly since I have validated it on debugging. The exception is thrown when trying to read the output response given from the server. This is the Error given
java.io.IOException: Server returned HTTP response code: 400 for URL:
However when I manually try to enter the Url from a web browser with a POST method chrome extension. I can view the response and everything works. So I am sure it has something to do with the following code where I make the connection and read/write.
URL obj = new URL(url);
HttpURLConnection connection = (HttpURLConnection) obj.openConnection();
//add request header
connection.setRequestMethod("POST");
connection.setRequestProperty("Content-Type", "application/json");
//mapping objects to json
BatchRequest requestParameters = new BatchRequest(o,d);
ObjectMapper mapper = new ObjectMapper();
String json = mapper.writeValueAsString(requestParameters);
connection.setDoOutput(true);
DataOutputStream os = new DataOutputStream(connection.getOutputStream());
os.writeBytes(json);
os.flush();
os.close();
// this is where the program throws the exception
BufferedReader in = new BufferedReader(new InputStreamReader(connection.getInputStream()));
String inputLine;
StringBuilder response = new StringBuilder();
while ((inputLine = in.readLine()) != null) {
response.append(inputLine);
}
in.close();
Both the URL and the JSON request are correct since They work when I try a manual conenction over a browser.
A DataOutputStream is not needed. Just:
OutputStream os = con.getOutputStream();
I'm trying to send a get request in order to get a website content.
When I'm using Postman it takes about 70-100 ms, but when I use the following code:
String getUrl = "someUrl";
URL obj = new URL(getUrl);
HttpURLConnection con = (HttpURLConnection) obj.openConnection();
// optional default is GET
con.setRequestMethod("GET");
//add request header
con.setRequestProperty("User-Agent", "Mozilla/5.0");
BufferedReader in = new BufferedReader(new InputStreamReader(con.getInputStream()));
String inputLine;
StringBuffer response = new StringBuffer();
while ((inputLine = in.readLine()) != null)
{
response.append(inputLine);
}
in.close();
response.toString();
it takes about 3-4 seconds.
Any idea how to get my code work as fast as Postman?
Thanks.
Try to find a workaround for the while loop. Maybe that is your bottleneck. What are you even getting from your URL? Json object or something else?
Try http-request built on apache http api.
HttpRequest<String> httpRequest = HttpRequestBuilder.createGet(someUri, String.class)
.responseDeserializer(ResponseDeserializer.ignorableDeserializer())
.addDefaultHeader("User-Agent", "Mozilla/5.0")
.build();
public void send(){
String response = httpRequest.execute().get();
}
I higly recomend read documentation before use.
I'm trying to send a PUT request from a Java app to a server. I successfully send GET, POST and DELETE requests but the PUT one won't succeed (I'm getting a 401 Error with the code below, 405 Error with an other code using the HttpPut of the apache package).
I'm using java.net.HttpURLConnection, here is a small region of my code :
URL obj = new URL(urlPost);
HttpURLConnection con = (HttpURLConnection) obj.openConnection();
//add request header
con.setRequestMethod(typeRequest); //typeRequest = PUT
String credentials = adminOC + ":" + pwdOC;
String encoding = Base64.encode(credentials.getBytes("UTF-8"));
con.setRequestProperty("Authorization", String.format("Basic %s", encoding));
if (!typeRequest.equals("GET")){
con.setDoOutput(true);
try (DataOutputStream wr = new DataOutputStream(con.getOutputStream())) {
wr.writeBytes(postParam);
wr.flush();
}
}
if (con.getResponseCode() == 200){
try (BufferedReader in = new BufferedReader(
new InputStreamReader(con.getInputStream()))) {
String inputLine;
while ((inputLine = in.readLine()) != null) {
response += inputLine;
}
}
}
I tried sending my PUT parameters the "POST" way and also directly in the URL.
It seems to be an error from my Java code and not from the server because I tried to do the PUT request with cURL and it worked.
Thanks for reading, I hope you will be able to give me some hints to debug the problem.
What is missing in your code is con.setRequestProperty("Content-Type", "application/x-www-form-urlencoded")
I have returning response to client as
return Response.status(200).entity("Data was succesfully loaded into database").build();
I have to read this on client my client code
URL url=new URL(urlString);
// URLConnection connection=url.openConnection();
//connection.setDoOutput(true);
HttpURLConnection httpCon = (HttpURLConnection) url.openConnection();
httpCon.setDoOutput(true);
httpCon.setRequestMethod("POST");
httpCon.setRequestProperty("Content-Type",
"application/json");
how to read these type of responses on client side
Once you have HttpURLConnection you can send data to the server (if this is needed, but looks like as it is, because you have POST request):
DataOutputStream wr = new DataOutputStream(httpCon.getOutputStream());
wr.writeBytes(yourData);
wr.flush();
wr.close();
Then you can check for response code (for e.g. if it is 200):
int responseCode = httpCon.getResponseCode();
And read data from response:
BufferedReader in = new BufferedReader(
new InputStreamReader(httpCon.getInputStream()));
String line;
StringBuffer response = new StringBuffer();
while ((line = in.readLine()) != null) {
response.append(inputLine);
}
in.close();
If you want to parse JSON you can use org.json or Gson.
I am trying to send an HTTP POST Request to a remote server using an instance of the HttpURLConnection class. Although, I am able to get a response code and a response message, when I try to write the input stream into a StringBuffer, I am not able to actually read any lines.
When I analyzed the packets sent from WireShark, I noticed that a full response was being sent from the remote server. My only guess as to why I am not able to see it in the Java program is because the time in which I try to read from the InputStream is too late.
So, how do I read the immediate, full response from the remote server using my HttpURLConnection object? Below is the code that I am using:
HttpURLConnection conn = null;
String urlStr = "...";
URL url = null;
try
{
url = new URL(urlStr);
conn = (HttpURLConnection) url.openConnection();
conn.setRequestMethod("POST");
conn.setDoInput(true);
conn.setDoOutput(true);
...
BufferedReader rd = new BufferedReader(
new InputStreamReader(conn.getInputStream()));
StringBuilder sb = new StringBuilder();
String line;
while ((line = rd.readLine()) != null)
{
sb.append(line);
}
rd.close();
...
}...
Okay, never mind. It turns out that what I was looking for was in the HTTP Respone's header. So, I got what I needed by looking through its headers. ::Face Palm::