Keycloak Admin REST APIs - Create new user

CreateNewUser.java

import com.google.gson.Gson;

import java.io.*;
import java.net.HttpURLConnection;
import java.net.URL;
import java.util.ArrayList;

public class CreateNewUser implements Serializable {

    public static void main(String args[]) throws IOException {
        new CreateNewUser().createUser("user1", "üser1@gmail.com", "user1");
    }


    public int createUser(String username, String email, String password) throws IOException {

        String grant_type = "password";
        String port = "8081";
        String realm = "api";
        String server = "localhost";
        String content_type = "application/json";
        String method_type = "POST";
        String encode_type = "UTF-8";
        String bearerToken = new GetToken().getBearerToken();
        int responseCode = 0;

        ArrayList arrayList = new ArrayList();

        Credentials credentials = new Credentials();
        if (grant_type != null) {
            credentials.setType(grant_type);
        }
        credentials.setTemporary(true);
        if (password != null) {
            credentials.setValue(password);
        }
        arrayList.add(credentials);

        PostBody postBody = new PostBody();
        if (username != null) {
            postBody.setUsername(username);
        }
        if (email != null) {
            postBody.setEmail(email);
        }
        postBody.setCredentials(arrayList);

        try {

            Gson gson = new Gson();
            String jsonString = gson.toJson(postBody);

            URL url = new URL("http://" + server + ":" + port + "/auth/admin/realms/" + realm + "/users/");

            HttpURLConnection conn = (HttpURLConnection) url.openConnection();
            conn.setRequestMethod(method_type);
            conn.setRequestProperty("Content-Type", content_type);
            conn.setRequestProperty("Accept", content_type);
            conn.setDoOutput(true);
            conn.setRequestProperty("Authorization", "Bearer " + bearerToken.trim());

            OutputStream os = conn.getOutputStream();
            byte[] input = jsonString.getBytes(encode_type);
            os.write(input, 0, input.length);


            BufferedReader br = new BufferedReader(new InputStreamReader(conn.getInputStream(), encode_type));
            StringBuilder response = new StringBuilder();
            String responseLine = null;
            while ((responseLine = br.readLine()) != null) {
                response.append(responseLine.trim());
            }
            responseCode = conn.getResponseCode();

            System.out.println(responseCode);
        } catch (Exception e) {
            System.out.println(e.getMessage());
        }
        return responseCode;
    }


    public class PostBody implements Serializable {
        private String email;
        private String username;
        private ArrayList credentials;

        public PostBody() {
        }

        public String getEmail() {
            return email;
        }

        public void setEmail(String email) {
            this.email = email;
        }

        public String getUsername() {
            return username;
        }

        public void setUsername(String username) {
            this.username = username;
        }

        public ArrayList getCredentials() {
            return credentials;
        }

        public void setCredentials(ArrayList credentials) {
            this.credentials = credentials;
        }
    }

    public class Credentials implements Serializable {
        private String value;
        private Boolean temporary;
        private String type;

        public Credentials() {
        }

        public String getValue() {
            return value;
        }

        public void setValue(String value) {
            this.value = value;
        }

        public Boolean getTemporary() {
            return temporary;
        }

        public void setTemporary(Boolean temporary) {
            this.temporary = temporary;
        }

        public String getType() {
            return type;
        }

        public void setType(String type) {
            this.type = type;
        }
    }
}