title: Watson Conversation Service - Unauthorized: Access is denied due to invalid credentials
body: <p>I've tried to access the Watson Conversation Service via a Java Application. Therefore I created the Service on Bluemix an wrote a small Application.</p>
  
  <pre><code>package de.kkh.comp.WatsonDemo;
  
  import java.util.Collection;
  import java.util.HashMap;
  import java.util.Map;
  import java.util.Set;
  import java.util.Map.Entry;
  
  import com.ibm.watson.developer_cloud.conversation.v1.ConversationService;
  import com.ibm.watson.developer_cloud.conversation.v1.model.MessageRequest;
  import com.ibm.watson.developer_cloud.conversation.v1.model.MessageResponse;
  
  public class App {
  
  private static final String USERNAME = "{USERNAME}";
  private static final String PASSWORD = "{PASSWORD}";
  private static final String WORKSPACE_ID = "{WORKSPACE_ID}";
  
  public static void main(String[] args) {
      ConversationService service = new ConversationService(ConversationService.VERSION_DATE_2017_02_03);
      service.setUsernameAndPassword(USERNAME, PASSWORD);
  
      MessageRequest newMessage = new MessageRequest.Builder().inputText("Hallo").context(new HashMap&lt;String,Object&gt;()).build();
  
      MessageResponse response = service.message(WORKSPACE_ID, newMessage).execute();
  
      System.out.println(response);
  }
  }
  </code></pre>
  
  <p>I expect that i get a simple answer of the Watson Service. </p>
  
  <p>If I run the Application I got an Not Authorized Exception, although i use the credentials which are given by Bluemix.</p>
  
  <pre><code>Aug 02, 2017 7:56:19 PM okhttp3.internal.platform.Platform log
  INFORMATION: --&gt; POST https://gateway.watsonplatform.net/conversation/api/v1/workspaces/{WORKSPACE_ID}/message?version=2017-02-03 http/1.1 (39-byte body)
  Aug 02, 2017 7:56:20 PM okhttp3.internal.platform.Platform log
  INFORMATION: &lt;-- 401 Not Authorized https://gateway.watsonplatform.net/conversation/api/v1/workspaces/{WORKSPACE_ID}/message?version=2017-02-03 (214ms, unknown-length body)
  Aug 02, 2017 7:56:20 PM com.ibm.watson.developer_cloud.service.WatsonService processServiceCall
  SCHWERWIEGEND: POST https://gateway.watsonplatform.net/conversation/api/v1/workspaces/{WORKSPACE_ID}/message?version=2017-02-03, status: 401, error: Not Authorized
  Exception in thread "main" com.ibm.watson.developer_cloud.service.exception.UnauthorizedException: Unauthorized: Access is denied due to invalid credentials
      at com.ibm.watson.developer_cloud.service.WatsonService.processServiceCall(WatsonService.java:492)
      at com.ibm.watson.developer_cloud.service.WatsonService$2.execute(WatsonService.java:254)
      at de.kkh.comp.WatsonDemo.App.main(App.java:26)
  </code></pre>
  
  <p>I haven't any clue why i got this Exception. Any Ideas?</p>