This is the code that I am using for an HTTP connection:
HttpConnection connection = null;
// InputStream inputstream = null;
connection = (HttpConnection) Connector.open("http://www.google.com");
//HTTP Request
connection.setRequestMethod(HttpConnection.GET);
connection.setRequestProperty("Content-Type","//text plain");
connection.setRequestProperty("Connection", "close");
add(new LabelField(""+connection.getResponseMessage()));
connection.close();
This BlackBerry Development Guide titled "Code sample: Creating a connection over HTTP by using the first available transport" worked!!
ConnectionFactory connFact = new ConnectionFactory();
ConnectionDescriptor connDesc;
connDesc = connFact.getConnection("http://www.google.com");
if (connDesc != null) {
HttpConnection httpConn;
httpConn = (HttpConnection)connDesc.getConnection();
try {
final int iResponseCode = httpConn.getResponseCode();
UiApplication.getUiApplication().invokeLater(new Runnable() {
public void run() {
Dialog.alert("Response code: " +
Integer.toString(iResponseCode));
}
});
} catch (IOException e) {
System.err.println("Caught IOException: " + e.getMessage());
}
}
Related
From my Tomcat's servlet I execute an https connection to an external servlet.
This is the code:
HttpsURLConnection hpcon = null;
try {
URL url = new URL(surl);
hpcon = (HttpsURLConnection) url.openConnection();
hpcon.setRequestMethod("POST");
hpcon.setDoInput(true);
hpcon.setDoOutput(true);
hpcon.setUseCaches(false);
hpcon.setRequestProperty("Content-type", "application/x-www-form-urlencoded");
OutputStreamWriter wr = new OutputStreamWriter(hpcon.getOutputStream());
String params = "user=" + URLEncoder.encode(user, "UTF-8");
params += "&psswd=" + URLEncoder.encode(pssw, "UTF-8");
params += "&metodo=" + URLEncoder.encode(metodo, "UTF-8");
wr.write(params);
wr.flush();
wr.close();
hpcon.connect();
int respCode = hpcon.getResponseCode();
if (respCode == 200) {
BufferedReader br = new BufferedReader(new InputStreamReader(hpcon.getInputStream()));
String response = "";
String output;
while ((output = br.readLine()) != null) {
response += output;
}
if (response.indexOf("-") > 0) {
response = "-12";
System.out.println("ret = -12 - response = " + response);
}
br.close();
} else {
ret = "-11";
System.out.println("ret = -11 - respCode = " + respCode);
}
} catch (Exception e) {
e.printStackTrace();
ret = "-10";
System.out.println("ret = -10");
} finally {
if (hpcon != null) {
hpcon.disconnect();
}
}
Where surl is the full url of a servlet present in a different domain and the three parameters are read from a db table (the third really is fixed and is the operation that is make by the external servlet).
The result is:
ret = -11 - respCode = 404
Before make the connection I turn off the certificate's verify using the above code:
try {
TrustManager[] trustAllCerts = new TrustManager[]{new X509TrustManager() {
public java.security.cert.X509Certificate[] getAcceptedIssuers() {
return null;
}
public void checkClientTrusted(X509Certificate[] certs, String authType) {
}
public void checkServerTrusted(X509Certificate[] certs, String authType) {
}
}};
SSLContext sc = SSLContext.getInstance("SSL");
sc.init(null, trustAllCerts, new java.security.SecureRandom());
HttpsURLConnection.setDefaultSSLSocketFactory(sc.getSocketFactory());
HostnameVerifier allHostsValid = new HostnameVerifier() {
public boolean verify(String hostname, SSLSession session) {
return true;
}
};
HttpsURLConnection.setDefaultHostnameVerifier(allHostsValid);
} catch (Exception e) {
e.printStackTrace();
}
If I execute the same servlet manually from a browser with parameters in get mode all run correctly.
I tried to execute it on my code using the get mode and passing the three parameters in query string, but the result is the same.
How can I do to resolve the problem?
I have an android app which is making api requests to my server running Spring MVC. The RestController works fine when I make a request from the browser but it responds with 404 when I am making requests from android. Not sure why
Here is code snippet from Android app making requests
public class AsyncFetch extends AsyncTask<Pair<String, String>, String, String> {
public ProgressDialog pdLoading;
private HttpURLConnection conn;
private String urlStr;
private String requestMethod = "GET";
public AsyncFetch(String endpoint, Context ctx)
{
pdLoading = new ProgressDialog(ctx);
Properties reader = PropertiesReader.getInstance().getProperties(ctx, "app.properties");
String host = reader.getProperty("host", "10.0.2.2");
String port = reader.getProperty("port", "8080");
String protocol = reader.getProperty("protocol", "http");
String context = reader.getProperty("context", "");
this.urlStr = protocol+"://"+host+":"+port+context+endpoint;
}
#Override
protected void onPreExecute() {
super.onPreExecute();
//this method will be running on UI thread
pdLoading.setMessage("\tLoading...");
pdLoading.setCancelable(false);
pdLoading.show();
}
#Override
protected String doInBackground(Pair<String, String>... params) {
URL url;
try {
url = new URL(urlStr);
} catch (MalformedURLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
return e.toString();
}
try {
conn = (HttpURLConnection) url.openConnection();
conn.setReadTimeout(READ_TIMEOUT);
conn.setConnectTimeout(CONNECTION_TIMEOUT);
conn.setRequestMethod(requestMethod);
conn.setDoOutput(true);
} catch (IOException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
return e1.toString();
}
try {
int response_code = conn.getResponseCode();
// Check if successful connection made`enter code here`
if (response_code == HttpURLConnection.HTTP_OK) {
// Read data sent from server
InputStream input = conn.getInputStream();
BufferedReader reader = new BufferedReader(new InputStreamReader(input));
StringBuilder result = new StringBuilder();
String line;
while ((line = reader.readLine()) != null) {
result.append(line);
}
// Pass data to onPostExecute method
return (result.toString());
} else {
return ("unsuccessful");
}
} catch (IOException e) {
e.printStackTrace();
return e.toString();
} finally {
conn.disconnect();
}
}
Spring MVC Controller
#RestController
public class ApiController {
#RequestMapping(value = "homefeed", method=RequestMethod.GET)
public String homefeed(#RequestParam(value="userId", required = false) Integer id, #RequestParam(value="search", required = false) String search, #RequestParam(value="page", required = false, defaultValue = "0") Integer page) { ... }
}
localhost:8080/api/homefeed -- works
127.0.0.1:8080/api/homefeed -- works
My Public IP:8080/api/homefeed -- does not works
10.0.2.2:8080/api/homefeed -- android emulator to localhost -- does not work
10.0.2.2:8080/Some resource other than the api endpoint -- works
Any help is highly appreciable, have wasted quiet some time in debugging.
Here is client code
public static void uploadFiles() {
try (DirectoryStream<Path> ds = Files.newDirectoryStream(Paths.get(Parameter.UPLOAD_FILES_DIR), "{*.dat}")) {
for (Path path : ds) {
System.out.println(path);
URL url = new URL(Parameter.UPLOAD_URL);
HttpURLConnection conn = (HttpURLConnection)url.openConnection();
conn.setDoInput(true);
conn.setDoOutput(true);
conn.setRequestMethod("POST");
conn.setRequestProperty("Content-Type", "application/json; charset=UTF-8");
conn.setConnectTimeout(1000 * 20);
conn.setReadTimeout(1000 * 20);
send(conn, path);
receive(conn);
}
} catch (Exception ex) {
ex.printStackTrace();
}
}
public static void send(HttpURLConnection conn, Path path) throws Exception {
try (
BufferedOutputStream out = new BufferedOutputStream(conn.getOutputStream());
BufferedInputStream in = new BufferedInputStream(new FileInputStream(path.toFile()))
) {
byte[] buffer = new byte[1024];
int c = 0;
while ((c = in.read(buffer)) != -1) {
out.write(buffer, 0, c);
}
out.flush();
}
}
public static void receive(HttpURLConnection conn) throws Exception {
try (BufferedReader in = new BufferedReader(new InputStreamReader(conn.getInputStream()))) {
String str;
while ((str = in.readLine()) != null) {
System.out.println(str);
}
if (HttpURLConnection.HTTP_OK != conn.getResponseCode()) {
throw new Exception("Uploader response code: " + conn.getResponseCode());
}
}
}
Here is Servlet code:
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
System.out.println("Post request");
System.out.println(request.getContentLength());
try (BufferedReader br = new BufferedReader(new InputStreamReader(request.getInputStream()));
) {
String str;
while ((str = br.readLine()) != null) {
System.out.print(str);
}
} catch (Exception ex) {
ex.printStackTrace();
}
try (BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(response.getOutputStream()))) {
bw.write("Close connection!!!");
}
}
When i run client code in server console out appears
Post refquest
-1
request.getContentLength() always return -1
Why i cant send bytes to the servlet? Here is contains of file which bytes i am trying to send
["192","2","3","4","5","6","7","8","9","US"] ["194","2","3","4","5","6","7","8","9","US"]
Resovled. Problem was in "/" symbol in the end of url. it was absent. But in this case servlet has responded.
I was googling for a long time, but still can't find a solution to my case.
My Tomcat sometimes returns an exception :
Error in postRequest(): Server returned HTTP response code: 400 for URL: http://localhost:80/CITIUS2/webresources/entities.personainterna/
Sometimes it works and sometimes it returns this exception, so I really don't know what is the reason...
Connection function:
public static String excutePost(String targetURL, String urlParameters) throws UnsupportedEncodingException {
URL url;
HttpURLConnection connection = null;
String responseXML = null;
try {
//Create connection
url = new URL(targetURL);
connection = (HttpURLConnection) url.openConnection();
byte[] requestXML = urlParameters.getBytes();
connection.setRequestProperty("Content-Length", String.valueOf(requestXML.length));
connection.setRequestProperty("Content-Type", "application/xml; charset=utf-8");
connection.setRequestMethod("POST");
connection.setDoOutput(true);
connection.setDoInput(true);
// Send the String that was read into postByte.
OutputStream out = connection.getOutputStream();
out.write(requestXML);
out.close();
// Read the response and write it to standard out.
InputStreamReader isr = new InputStreamReader(connection.getInputStream());
BufferedReader br = new BufferedReader(isr);
String temp;
String tempResponse = "";
//Create a string using response from web services
while ((temp = br.readLine()) != null) {
tempResponse = tempResponse + temp;
}
responseXML = tempResponse;
br.close();
isr.close();
} catch (java.net.MalformedURLException e) {
System.out.println("Error in postRequest(): Secure Service Required");
} catch (Exception e) {
System.out.println("Error in postRequest(): " + e.getMessage());
}
return responseXML;
}
# Edit:
In general build is successful, there are no errors, only this one in the Apache Tomcat's output window.
Rest method:
#POST
#Consumes({"application/xml", "application/json"})
public Response create(Personainterna entity) {
try {
getJpaController().create(entity);
return Response.created(URI.create(entity.getPersonaId().toString())).build();
} catch (Exception ex) {
return Response.notModified(ex.getMessage()).build();
}
}
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I understand that there are already alot of web server out there.
But i feel like creating one for learning purpose.
Is it something i should try to figure out and any guides or tutorials on this?
In java:
Create a ServerSocket and have this continually listen for connections - when a connection request comes in handle it by by parsing the HTTP request header, get the resource indicated and add some header information before sending back to the client. eg.
public class Server implements Runnable {
protected volatile boolean keepProcessing = true;
protected ServerSocket serverSocket;
protected static final int DEFAULT_TIMEOUT = 100000;
protected ExecutorService executor = Executors.newCachedThreadPool();
public Server(int port) throws IOException {
serverSocket = new ServerSocket(port);
serverSocket.setSoTimeout(DEFAULT_TIMEOUT);
}
#Override
public void run() {
while (keepProcessing) {
try {
Socket socket = serverSocket.accept();
System.out.println("client accepted");
executor.execute(new HttpRequest(socket));
} catch (Exception e) {
}
}
closeIgnoringException(serverSocket);
}
protected void closeIgnoringException(ServerSocket serverSocket) {
if (serverSocket != null) {
try {
serverSocket.close();
} catch (IOException ignore) {
}
}
}
public static void main(String[] args) {
ExecutorService executor = Executors.newCachedThreadPool();
try {
executor.execute(new WebServer(6789));
} catch (Exception e) {
e.printStackTrace();
}
}
}
final class HttpRequest implements Runnable {
final static String CRLF = "\r\n";
private Socket socket;
public HttpRequest(Socket socket) {
this.socket = socket;
}
public void run() {
try {
processRequest();
} catch (Exception e) {
System.out.println(e);
}
}
private void processRequest() throws Exception {
DataOutputStream os = new DataOutputStream(socket.getOutputStream());
BufferedReader br = new BufferedReader(new InputStreamReader(socket
.getInputStream()));
String requestLine = br.readLine();
System.out.println();
System.out.println(requestLine);
List<String> tokens = Arrays.asList(requestLine.split(" "));
Iterator<String> it = tokens.iterator();
it.next(); // skip over the method, which should be "GET"
String fileName = it.next();
fileName = "." + fileName;
FileInputStream fis = null;
boolean fileExists = true;
try {
fis = new FileInputStream(fileName);
} catch (FileNotFoundException e) {
fileExists = false;
}
String statusLine = null;
String contentTypeLine = null;
String entityBody = null;
String contentType = null;
if (fileExists) {
statusLine = "HTTP/1.0 200 OK";
contentType = contentType(fileName);
contentTypeLine = "Content-type: " + contentType + CRLF;
} else {
statusLine = "HTTP/1.0 404 NOT FOUND";
contentType = "text/html";
contentTypeLine = "Content-type: " + contentType + CRLF;
entityBody = "<HTML>" + "<HEAD><TITLE>Not Found</TITLE></HEAD>"
+ "<BODY>" + statusLine + " Not Found</BODY></HTML>";
}
os.writeBytes(statusLine);
os.writeBytes(contentTypeLine);
os.writeBytes(CRLF);
if (fileExists) {
sendBytes(fis, os);
fis.close();
} else {
os.writeBytes(entityBody);
}
String headerLine = null;
while ((headerLine = br.readLine()).length() != 0) {
System.out.println(headerLine);
}
os.close();
br.close();
socket.close();
}
private static void sendBytes(InputStream fis, DataOutputStream os)
throws Exception {
byte[] buffer = new byte[1024];
int bytes = 0;
while ((bytes = fis.read(buffer)) != -1) {
os.write(buffer, 0, bytes);
}
}
private static String contentType(String fileName) {
if (fileName.endsWith(".htm") || fileName.endsWith(".html")) {
return "text/html";
}
if (fileName.endsWith(".jpg") || fileName.endsWith(".jpeg")) {
return "image/jpeg";
}
if (fileName.endsWith(".gif")) {
return "image/gif";
}
if (fileName.endsWith(".txt")) {
return "text/plain";
}
if (fileName.endsWith(".pdf")) {
return "application/pdf";
}
return "application/octet-stream";
}
}
A Simple Webserver in C++ for Windows
Hope this helps you ; )
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