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How to Call JAVA GET request with JSON Array as a parameters

Am trying to create a JAVA GET Http connection request with JSON Array data as shown below. where as the same code works with out any parameter (i.e. ?data={..})
String myurl = "https://myserver.com/test/api/v1/parameter?data={"username":{"name":"testusername"},"salary":{"sal":"56748","bonus":"3221"},"category":{"cat":"CATA"}}";
String newmyurl = myurl.replaceAll("\"","\\\"");
log.info("**newmyurl*** "+newmyurl);
URL url = new URL(newmyurl);
log.info("**URL*** "+url);
HttpURLConnection con = (HttpURLConnection) url.openConnection();
// By default it is GET request
con.setRequestMethod("GET");
con.setRequestProperty("Accept", "application/json");
int responseCode = con.getResponseCode(); // Code breaks here nothing errors in log
BufferedReader in = new BufferedReader(new InputStreamReader(con.getInputStream()));
String output;
StringBuffer sb = new StringBuffer();
while ((output = in.readLine()) != null) {
sb.append(output);
}
in.close();
//printing result from response
log.info("****return string****"+sb.toString());

To escape characters in a URL, use URLEncoder:
String myjson = "{\"username\":{\"name\":\"testusername\"},\"salary\":{\"sal\":\"56748\",\"bonus\":\"3221\"},\"category\":{\"cat\":\"CATA\"}}";
String myurl = "https://myserver.com/test/api/v1/parameter?data=" + URLEncoder.encode(myjson, "UTF-8");

Send JSON data through POST in Java

I have this code to send JSON data (passed as a string) to the server (This code works when English characters are to be sent as values in dataJSON as far as I tested):
private static String sendPost(String url, String dataJSON) throws Exception {
System.out.println("Data to send: " + dataJSON);
URL obj = new URL(url);
HttpURLConnection con = (HttpURLConnection) obj.openConnection();
String type = "application/json;charset=utf-8";
// add reuqest header
con.setRequestMethod("POST");
con.setRequestProperty("User-Agent", "Mozilla/5.0");
con.setRequestProperty("Accept-Language", "en-US,en;q=0.5");
con.setRequestProperty("Content-Length", String.valueOf(dataJSON.getBytes("UTF-8").length));
con.setRequestProperty("Content-Type", type);
// Send post request
con.setDoOutput(true);
DataOutputStream wr = new DataOutputStream(con.getOutputStream());
wr.writeUTF(dataJSON);
wr.flush();
wr.close();
int responseCode = con.getResponseCode();
System.out.println("\nSending 'POST' request to URL : " + url);
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();
System.out.print("Response string from POST: " + response.toString() + "\n");
return response.toString();
}
Problem is I don't get correct response, which I get for example using DHC Restlet Client.
The problem is I think the dataJSON must be encoded in UTF8. That's how the server expects it most likely.
But it seems I have some problem in code the way I try to convert it and send it.
Can someone help me send data in body as UTF8 string in above example?

I think I solved with this approach:
private static String sendPost2(String urlStr, String dataJSON) throws Exception {
URL url = new URL(urlStr);
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
conn.setConnectTimeout(5000);
conn.setRequestProperty("Content-Type", "application/json; charset=UTF-8");
conn.setDoOutput(true);
conn.setDoInput(true);
conn.setRequestMethod("POST");
OutputStream os = conn.getOutputStream();
os.write(dataJSON.getBytes("UTF-8"));
os.close();
// read the response
InputStream in = new BufferedInputStream(conn.getInputStream());
String result = new BufferedReader(new InputStreamReader(in)) .lines().collect(Collectors.joining("\n"));
in.close();
conn.disconnect();
return result;
}
Please suggest alternative if you see problem with it.

Get the Response from POST request

I would like to obtain the response from a HttpsURLConnection POST request.
If I try to do the request with PostMan, I have one message as response (es: 1520). I have to save this code, but I find the method for read just the getResponseCode() (200) or getResponseMessage() ("OK"). I should use another libraries? Because in the HttpsUrlConnection method I don't find anything useful (https://docs.oracle.com/javase/7/docs/api/java/net/HttpURLConnection.html)
My code is:
HttpsURLConnection con = (HttpsURLConnection) obj.openConnection();
con.setSSLSocketFactory(sslContext.getSocketFactory());
con.setDoOutput(true);
con.setUseCaches(false);
con.setRequestMethod("POST");
con.setRequestProperty("Connection", "keep-alive");
con.setRequestProperty("Content-Type", w_AECONTYP);
con.setRequestProperty("Accept-Charset", w_AEACCCHA);
con.setRequestProperty("Accept-Encoding", w_AEACCENC);
StringBuilder postFile = new StringBuilder();
byte[] postFileBytes =w_FileToSend.getBytes("UTF-8");
con.setDoOutput(true);
try {
DataOutputStream wr = new DataOutputStream(con.getOutputStream());
wr.write(postFileBytes);
wr.flush();
wr.close();
} catch (Exception e) {
System.out.println("Connection Failed");
e.printStackTrace();
}
int responseCode = con.getResponseCode();
// get 200 code "OK"
BufferedReader in = new BufferedReader(new InputStreamReader(con.getInputStream()));
String inputLine;
StringBuffer response = new StringBuffer();
while ((inputLine = in.readLine()) != null) {
response.append(inputLine);
}
in.close();
But when arrived at the WHILE loop, it doesn't enter in the cycle.
How I can do this?
The file is in JSON format, but that isn't the problem.
I need to save that 915 code!!

You could use HttpResponse and HttpPost for getting a response from server (as well as the Response Code):
HttpResponse httpResponse = httpClient.execute(new HttpPost(URL));
InputStream inputStream = httpResponse.getEntity().getContent();
InputStreamReader inputStreamReader = new InputStreamReader(inputStream);
BufferedReader bufferedReader = new BufferedReader(inputStreamReader);
StringBuilder stringBuilder = new StringBuilder();
String bufferedStrChunk = null;
while((bufferedStrChunk = bufferedReader.readLine()) != null){
stringBuilder.append(bufferedStrChunk);
}
// now response is in the stringBuilder.toString()
I hope this will help you.

Upload image from Java to PHP

I've got a webserver setup ready to receive images and I'd like to have a client in Java send the image along with two POST arguments, upon searching the web I only found ways to do this with Apache's API but I'd prefer to do this in vanilla Java.
Any help will be appreciated.

Something along the lines of...
String url = "https://asite.com";
URL obj = new URL(url);
HttpsURLConnection con = (HttpsURLConnection) obj.openConnection();
//add reuqest header
con.setRequestMethod("POST");
con.setRequestProperty("User-Agent", USER_AGENT);
con.setRequestProperty("Accept-Language", "en-US,en;q=0.5");
String urlParameters = "aparam=1&anotherparam=2";
// Send post request
con.setDoOutput(true);
DataOutputStream wr = new DataOutputStream(con.getOutputStream());
wr.writeBytes(urlParameters);
wr.flush();
wr.close();
int responseCode = con.getResponseCode();
BufferedReader in = new BufferedReader(
new InputStreamReader(con.getInputStream()));
String inputLine;
StringBuffer response = new StringBuffer();
while ((inputLine = in.readLine()) != null) {
response.append(inputLine);
}
in.close();
You can add more headers, and add more to the output stream as required.

404 Error when sending HTTP request through java

I seem to be getting a 404 error when sending a http post to a sinatra server. I am trying to make the server page the text I send to it, here's my code I think it may be something wrong with my server but I'm not sure:
private void sendInfo() throws Exception {
//make the string and URL
String url = "http://localhost";
URL obj = new URL(url);
HttpsURLConnection con = (HttpsURLConnection) obj.openConnection();
//add request header
con.setRequestMethod("POST");
con.setRequestProperty("User-Agent", USER_AGENT);
con.setRequestProperty("Accept-Language", "en-US,en;q=0.5");
String urlParameters = "sn=C02G8416DRJM&cn=&locale=&caller=&num=12345";
//send post
con.setDoOutput(true);
DataOutputStream wr = new DataOutputStream(con.getOutputStream());
wr.writeBytes(urlParameters);
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());
}
and here is the sinatra server (ruby):
require 'sinatra'
get '/' do
'hello mate'
end
get '/boo' do
'trololo'
end

Could your problem be realated to trying to use a HTTPS (instead of HTTP) connections? I am looing at the use of HttpsURLConnection.

Since you're sending your HTTP request via POST, shouldn't your sinatra server routes bet post instead of get? Would explain why you're getting a 404. Something like this should sort it out:
require 'sinatra'
post '/' do
'hello mate'
end
post '/boo' do
'trololo'
end