I can't understand how to switch to POST method in my HttpsURLConnection. On the debugger the request method is GET also after the setRequestMethod method. Can you tell me where is my mistake?
try {
URL url=new URL("https://smartmates.herokuapp.com");
HttpsURLConnection connection= (HttpsURLConnection) url.openConnection();
connection.setRequestMethod("POST");
connection.setDoInput(true);
connection.setDoOutput(true);
//I'll add some params here
connection.disconnect();
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
Thank you very much.
This is a piece of code that I use to POST the String mensaje and receiving rta.ToString(). I think that DoSetInput(true) is a mistake, because you want to send a POST (output) and, eventually, get a response.
`
String urlParametros = "<?xml version=\"1.0\"?>";
urlParametros = urlParametros + mensaje;
byte[] postDatos = urlParametros.getBytes(StandardCharsets.UTF_8);
try {
URL miurl = new URL(url);
con = (HttpURLConnection) miurl.openConnection();
con.setDoOutput(true);
con.setRequestMethod("POST");
//******…………..
con.setRequestProperty("User-Agent", "Java client");
con.setRequestProperty("Content-Type", "text/xml");
try (DataOutputStream datos = new DataOutputStream(con.getOutputStream())) {
datos.write(postDatos);
}
StringBuilder rta;
try (BufferedReader entrada = new BufferedReader(
new InputStreamReader(con.getInputStream()))) {
String linea;
rta = new StringBuilder();
while ((linea = entrada.readLine()) != null) {
rta.append(linea);
rta.append(System.lineSeparator());
}
}
return rta.toString();
} finally {
con.disconnect();
}´
Hope it helps
Daniel
Related
I'm a QA with desire to learn more about Java programming and problem I'm experiencing is this:
I'm trying to POST Employee data to the database of some fake Rest API, but I'm getting
Cannot write to a URLConnection if doOutput=false - call
setDoOutput(true)"
So far, I tried some ideas from StackOverflow, but inexperienced as I am, I could easily fall deeper into a problem.
So URL is: http://dummy.restapiexample.com/api/v1/create and firstly I created an Employee class of json object:
public class Main {
public static void main(String[] args) {
new Main();
}
public Main() {
Employees em = new Employees();
em.setEmployeeName("Alex");
em.setEmployeeSalary("1234");
em.setEmployeeAge("28");
try{
URL url = new URL("http://dummy.restapiexample.com/api/v1/create");
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setRequestMethod("POST");
conn.setRequestProperty("Accept", "application/json");
if (conn.getResponseCode() != 200) {
throw new RuntimeException("Unsuccessful call: HTTP error : "
+ conn.getResponseCode());
}
// URLConnection urlc = url.openConnection();
// urlc.setDoOutput(true);
PrintWriter pw = new PrintWriter(conn.getOutputStream());
pw.print(new Gson().toJson(em));
pw.close();
pw.flush();
BufferedReader br = new BufferedReader(
new InputStreamReader(conn.getInputStream())
);
String json = "";
String output;
while ((output = br.readLine()) != null) {
json += output;
}
conn.disconnect();
System.out.println("Employee name: " + em.getEmployeeName());
}
catch (MalformedURLException e) {
e.printStackTrace();
}
catch (IOException e) {
e.printStackTrace();
}
}
}
Well, using one of your ideas and added next lines of code (it's commented in above code):
URLConnection urlc = url.openConnection();
urlc.setDoOutput(true);
So the code looks like:
public class Main {
public static void main(String[] args) {
new Main();
}
public Main() {
Employees em = new Employees();
em.setEmployeeName("Alex");
em.setEmployeeSalary("1234");
em.setEmployeeAge("28");
try{
URL url = new URL("http://dummy.restapiexample.com/api/v1/create");
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setRequestMethod("POST");
conn.setRequestProperty("Accept", "application/json");
if (conn.getResponseCode() != 200) {
throw new RuntimeException("Unsuccessful call: HTTP error : "
+ conn.getResponseCode());
}
URLConnection urlc = url.openConnection();
urlc.setDoOutput(true);
PrintWriter pw = new PrintWriter(urlc.getOutputStream());
pw.print(new Gson().toJson(em));
pw.close();
pw.flush();
BufferedReader br = new BufferedReader(new InputStreamReader(
(urlc.getInputStream())));
String json = "";
String output;
while ((output = br.readLine()) != null) {
json += output;
}
conn.disconnect();
System.out.println("Employee name: " + em.getEmployeeName());
}
catch (MalformedURLException e) {
e.printStackTrace(); }
catch (IOException e) {
e.printStackTrace();
}
}}
With this second code I'm not getting that error, but there is no inserting to the database(checking that using postman, with GET method)...
Well, what am I missing? I guess, I'm missing something basic...
Using url.openConnection twice means you get two different connections. You send the request to the second connection, and try to read the response from the first connection. You should call doOutput on the connection you open originally.
The second problem is you're calling getResponseCode before the request is sent. In http, the request must be sent entirely before the server sends a response. You should move the code that calls doOutput and writes the request body before the code that tries to check the response code.
I am trying to make a post from Java to make a market order using my Bitstamp account but the following code is returning a file not found for the URL.
It may be because of CSRF but I am unsure, if anyone has had any experience with the bitstamp API that would be great.
public static void postToken() throws IOException, JSONException {
URL url = null;
String sig = encode();
try {
url = new URL("https://www.bitstamp.net/api/v2/buy/market/" + feedbackType.toLowerCase() +"usd/");
HttpURLConnection connection = (HttpURLConnection) url.openConnection();
connection.setConnectTimeout(5000);//5 secs
connection.setReadTimeout(5000);//5 secs
connection.setRequestMethod("POST");
connection.setDoOutput(true);
connection.setRequestProperty("Content-Type", "application/json; charset=UTF-8");
JSONObject cred = new JSONObject();
cred.put("key",api_key);
cred.put("signature", sig);
cred.put("nonce", nonce);
cred.put("amount", feedback);
OutputStreamWriter out = new OutputStreamWriter(connection.getOutputStream());
out.write(cred.toString());
out.flush();
out.close();
int res = connection.getResponseCode();
System.out.println(res);
InputStream is = connection.getInputStream();
BufferedReader br = new BufferedReader(new InputStreamReader(is));
String line = null;
while((line = br.readLine() ) != null) {
Log.d(TAG, line);
}
connection.disconnect();
} catch (MalformedURLException e) {
e.printStackTrace();
}
}
Error: W/System.err: java.io.FileNotFoundException: https://www.bitstamp.net/api/v2/buy/market/btcusd/
I have the below small code to get the json reply from service providers, what i have tried is that to post a http post request but it always throws
java.net.UnknownHostException: directory.qantasloyalty.com
at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:177)
at java.net.Socket.connect(Socket.java:519)
at java.net.Socket.connect(Socket.java:469)
at sun.net.NetworkClient.doConnect(NetworkClient.java:157)
at sun.net.www.http.HttpClient.openServer(HttpClient.java:382)
at sun.net.www.http.HttpClient.openServer(HttpClient.java:509)
at sun.net.www.protocol.https.HttpsClient.<init>(HttpsClient.java:278)
at sun.net.www.protocol.https.HttpsClient.New(HttpsClient.java:335)
at sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.getNewHttpClient(AbstractDelegateHttpsURLConnection.java:176)
at sun.net.www.protocol.http.HttpURLConnection.plainConnect(HttpURLConnection.java:769)
at sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.connect(AbstractDelegateHttpsURLConnection.java:162)
at sun.net.www.protocol.http.HttpURLConnection.getOutputStream(HttpURLConnection.java:861)
at sun.net.www.protocol.https.HttpsURLConnectionImpl.getOutputStream(HttpsURLConnectionImpl.java:230)
at Test.Httptestpost.sendPost(Httptestpost.java:124)
at Test.Httptestpost.main(Httptestpost.java:32)
PLease find my code below,
private void sendPost() {
System.getProperties().put("http.proxySet", "true");
System.getProperties().put("http.proxyHost", "proxyurl");
System.getProperties().put("http.proxyPort", "8080");
System.getProperties().put("http.proxyUser", "username");
System.getProperties().put("http.proxyPassword", "pwd");
System.getProperties().put("http.nonProxyHosts", "localhost|127.0.0.1");
String url = "httpsurlhere";
URL obj = null;
try {
obj = new URL(url);
} catch (MalformedURLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
HttpsURLConnection con = null;
try {
con = (HttpsURLConnection) obj.openConnection();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
//add reuqest header
try {
con.setRequestMethod("POST");
} catch (ProtocolException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
//con.setRequestProperty("User-Agent", USER_AGENT);
//con.setRequestProperty("Accept-Language", "en-US,en;q=0.5");
con.setRequestProperty("Content-Type", "application/json;UTF-8");
String urlParameters = "username=demouser&password=aDemoPassword";
String input = "{\"username\":\"demouser\",\"password\":\"aDemoPassword\"}";
System.out.println("input"+input);
System.out.println("url"+con.getURL());
System.out.println("req prop :"+con.getRequestProperties());
// Send post request
con.setDoOutput(true);
DataOutputStream wr;
try {
wr = new DataOutputStream(con.getOutputStream());
wr.writeBytes(input);
wr.flush();
wr.close();
int responseCode = con.getResponseCode();
System.out.println("\nSending 'POST' request to URL : " + url);
System.out.println("Post parameters : " + urlParameters);
System.out.println("Response Code : " + responseCode);
BufferedReader in = new BufferedReader(
new InputStreamReader(con.getInputStream()));
String inputLine;
StringBuffer response = new StringBuffer();
while ((inputLine = in.readLine()) != null) {
response.append(inputLine);
}
in.close();
//print result
System.out.println(response.toString());
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
Can someone please help me to route the cause
For security purpose I have not shared the exact proxy URL and http post webservice URl also here
please go through these sample codes:-
public static String handlePostRequest(String X, String Y)
throws IOException {
URL url = new URL(X);
HttpURLConnection connection = (HttpURLConnection) url.openConnection();
connection.setDoOutput(true);
connection.setRequestMethod("POST");
connection.setRequestProperty("Content-Type", "application/json");
connection.setRequestProperty("Content-Length",
String.valueOf(Y.length()));
// Write data
OutputStream os = connection.getOutputStream();
os.write(Y.getBytes());
// Read response
String responseSB = "";
BufferedReader br = new BufferedReader(new InputStreamReader(
connection.getInputStream()));
String line;
while ((line = br.readLine()) != null)
responseSB += line;
// Close streams
br.close();
os.close();
return responseSB;
}
Can anyone spot why this takes ~20 sec?
I am running the code below to post a JSON request to a local server 192.168.1.127.
curl -H "Content-type: application/json" -X POST
http:// 192.168.1.127:8080/bed -d
'{"command":{"value":3.012,"set":"target_pressure_voltage"},"id":2002,"side":"left","role":"command"}'
curl on the same box where the server is running is instant and the server does not complain.
A get request from the Android browser is fast. I have tried two Android devices with os version 4.x.
This question does not help as far as I can tell:
Android HttpURLConnection VERY slow
con.getInputStream() Takes ~20 sec:
String httpJson(String url, JSONObject job) {
String ret = null;
HttpURLConnection con = httpJsonCon(url);
if(con!=null)
httpJsonCon(con, url,job);
return ret;
}
HttpURLConnection mkCon(String url) {
HttpURLConnection con = null;
URL u = null;
try {
u = new URL(url);
con = (HttpURLConnection) (u.openConnection());
con.setRequestMethod("POST");
con.setUseCaches(false);
con.setRequestProperty("Content-Type", "application/json");
con.setRequestProperty("Accept", "text/plain");
con.setRequestProperty("Accept", "application/json");
con.setDoOutput(true);
con.setDoInput(true);
con.connect();
} catch (Exception e) {
Log.w(TAG, " e= " + e);
if(con!=null)
con.disconnect();
con = null;
}
return con;
}
String sendJson(HttpURLConnection con, JSONObject job) {
String ret = null;
if(con==null){
return ret;
}
try {
final String toWriteOut = job.toString();
final Writer out = new OutputStreamWriter(new BufferedOutputStream(
con.getOutputStream()), "UTF-8");
out.write(toWriteOut);
out.flush();
//con.getInputStream() Takes ~20 sec:
final BufferedReader in = new BufferedReader(new InputStreamReader(con.getInputStream()));
} catch (IOException e) {
Log.d(TAG, " e= " + e);
ret = null;
} finally {
if(con!=null)
con.disconnect();
}
return ret;
}
Add a request header that specifies the post content length.
con.setRequestProperty("Content-Length", "" + json.length());
I try to send post request, but webserver returns that I added no post-values. I spent a lot of time trying to solve this issue, but no result. Here is the code:
public static String post(String url, String postParams)
{
URLConnection connection = null;
try
{
connection = initializeConnection(url);
connection.setDoOutput(true);
((HttpURLConnection) connection).setRequestMethod("POST");
connection.setRequestProperty("Content-Type", "text/xml");
connection.setRequestProperty("Accept", "text/xml");
connection.setUseCaches(false);
connection.setDoInput(true);
DataOutputStream wr = new DataOutputStream(connection.getOutputStream());
wr.write(postParams.getBytes());
wr.flush();
wr.close();
// Get Response
InputStream is = connection.getInputStream();
return inputStreamToString(is);
}
catch (Exception e)
{
e.printStackTrace();
return null;
}
}
protected static HttpURLConnection initializeConnection(String stringUrl)
{
HttpURLConnection connection;
URL url = null;
try
{
url = new URL(stringUrl);
}
catch (MalformedURLException e1)
{
e1.printStackTrace();
}
try
{
connection = (HttpURLConnection) url.openConnection();
connection.setConnectTimeout(5000);
}
catch (Exception e)
{
e.printStackTrace();
return null;
}
return connection;
}
public static String inputStreamToString(InputStream is)
{
BufferedReader r = new BufferedReader(new InputStreamReader(is));
StringBuilder total = new StringBuilder();
String line;
try
{
while ((line = r.readLine()) != null)
{
total.append(line);
}
}
catch (IOException e)
{
e.printStackTrace();
}
return total.toString();
}
I receive a message from webserver where it is told that no post-values are added. As far as I understand from the code, the values are added. I'm stuck.
It turned out that all I had to do was to replace
connection.setRequestProperty("Content-Type", "text/xml");
with
connection.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");
So simple and so much time spent to clear it out...
By the way, how could I know that server requires this header? I thought that all the work that is essential to the request would be automatically done by java..
P.S. Installing fiddler helped to solve the issue, thanks for that.
debug the 'postParams' parameter and check what been sent.