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javaapirestweb-serviceshttpurlconnection

Calling Post request without body in java


I have a post API which doesn't accept any input. I have to get output from API. But it is giving compilation error.

HttpURLConnection connection = null;
String targetUrl="https://idcs-oda-9417f93560b94eb8a2e2a4c9aac9a3ff-t0.data.digitalassistant.oci.oc-test.com/api/v1/bots/"+BotID+"/dynamicEntities/"+dynamicEntityId+"/pushRequests
URL url = new URL(targetUrl);
connection=(HttpURLConnection) url.openConnection();
connection.setUseCaches (false);
connection.setDoInput(true);
connection.setDoOutput(true);
connection.setRequestMethod("POST");
connection.setRequestProperty("Content-Type","application/x-www-form-urlencoded");
connection.setRequestProperty("Authorization", "Basic aWRjcy1vZGEtOTQxN2Y5MzU2MGI5NGViOGEyZTJhNGM5YWFjOWEzZmYtdDBfQVBQSUQ6MjQ0YWU4ZTItNmY3MS00YWYyLWI1Y2MtOTExMDg5MGQxNDU2");
connection.setRequestProperty("Accept", "application/json");
OutputStream os = connection.getOutputStream();
OutputStreamWriter osw = new OutputStreamWriter(os, "UTF-8");    
**osw.write();**   //this line is expecting input in parameter
osw.flush();
osw.close();
os.close(); 
connection.connect();

If I dont pass any value in osw.write() it gives compilation error. How can I resolve the same.


Solution

  • Look at the following method for the post call. You will need to add the outputstream to the osw.write() as it expects a parameter.

    private static void sendPOST() throws IOException {
        URL obj = new URL(POST_URL);
        HttpURLConnection con = (HttpURLConnection) obj.openConnection();
        con.setRequestMethod("POST");
        con.setRequestProperty("User-Agent", USER_AGENT);
    
        // For POST only - START
        con.setDoOutput(true);
        OutputStream os = con.getOutputStream();
        os.write(POST_PARAMS.getBytes());
        os.flush();
        os.close();
        // For POST only - END
    
        int responseCode = con.getResponseCode();
        System.out.println("POST Response Code :: " + responseCode);
    
        if (responseCode == HttpURLConnection.HTTP_OK) { //success
            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());
            } 
        else {
            System.out.println("POST request not worked");
        }
    }
    

    For more details on the above code look here.