Program: 88549
Project: 88549
Buggy source:
public static String sendCredentials(Project project,String username,String password) throws ServerException, IOException, URISyntaxException {
  URIBuilder requestUri=MMSUtils.getServiceUri(project);
  if (requestUri == null) {
    return null;
  }
  requestUri.setPath(requestUri.getPath() + "String_Node_Str");
  requestUri.clearParameters();
  ObjectNode credentials=JacksonUtils.getObjectMapper().createObjectNode();
  credentials.put("String_Node_Str",username);
  credentials.put("String_Node_Str",password);
  ContentType contentType=ContentType.APPLICATION_JSON;
  URI requestDest=requestUri.build();
  HttpRequestBase request=new HttpPost(requestDest);
  request.addHeader("String_Node_Str","String_Node_Str");
  request.addHeader("String_Node_Str",(Consts.UTF_8).displayName());
  String data=JacksonUtils.getObjectMapper().writeValueAsString(credentials);
  ((HttpEntityEnclosingRequest)request).setEntity(new StringEntity(data,ContentType.APPLICATION_JSON));
  System.out.println("String_Node_Str" + requestUri.toString());
  ObjectNode responseJson=null;
  try (CloseableHttpClient httpclient=HttpClients.createDefault();CloseableHttpResponse response=httpclient.execute(request);InputStream inputStream=response.getEntity().getContent()){
    int responseCode=response.getStatusLine().getStatusCode();
    String responseBody=((inputStream != null) ? IOUtils.toString(inputStream) : "String_Node_Str");
    String responseType=((response.getEntity().getContentType() != null) ? response.getEntity().getContentType().getValue() : "String_Node_Str");
    System.out.println("String_Node_Str" + requestUri.toString() + "String_Node_Str"+ responseCode);
    boolean throwServerException=false;
    if (responseCode != 200) {
      Application.getInstance().getGUILog().log("String_Node_Str" + responseCode);
      throwServerException=true;
    }
    if (!responseBody.isEmpty() && responseType.equals("String_Node_Str")) {
      responseJson=JacksonUtils.getObjectMapper().readValue(responseBody,ObjectNode.class);
      JsonNode value;
      if (responseJson != null && (value=responseJson.get("String_Node_Str")) != null && value.isTextual() && !value.asText().isEmpty()) {
        Application.getInstance().getGUILog().log("String_Node_Str" + value.asText());
      }
      if (responseJson != null && (value=responseJson.get("String_Node_Str")) != null && value.isArray()) {
        ArrayNode msgs=(ArrayNode)value;
        for (        JsonNode msg : msgs) {
          if (msg != null && (value=msg.get("String_Node_Str")) != null && value.isTextual() && !value.asText().isEmpty()) {
            Application.getInstance().getGUILog().log("String_Node_Str" + value.asText());
          }
        }
      }
    }
    if (throwServerException) {
      Utils.showPopupMessage("String_Node_Str");
      throw new ServerException(responseBody,responseCode);
    }
  }
   JsonNode value;
  if (responseJson != null && (value=responseJson.get("String_Node_Str")) != null && (value=value.get("String_Node_Str")) != null && value.isTextual()) {
    return value.asText();
  }
  return null;
}

Fixed version (ground truth):
public static String sendCredentials(Project project,String username,String password) throws ServerException, IOException, URISyntaxException {
  URIBuilder requestUri=MMSUtils.getServiceUri(project);
  if (requestUri == null) {
    return null;
  }
  requestUri.setPath(requestUri.getPath() + "String_Node_Str");
  requestUri.clearParameters();
  ObjectNode credentials=JacksonUtils.getObjectMapper().createObjectNode();
  credentials.put("String_Node_Str",username);
  credentials.put("String_Node_Str",password);
  ContentType contentType=ContentType.APPLICATION_JSON;
  URI requestDest=requestUri.build();
  HttpRequestBase request=new HttpPost(requestDest);
  request.addHeader("String_Node_Str","String_Node_Str");
  request.addHeader("String_Node_Str",(Consts.UTF_8).displayName());
  String data=JacksonUtils.getObjectMapper().writeValueAsString(credentials);
  ((HttpEntityEnclosingRequest)request).setEntity(new StringEntity(data,ContentType.APPLICATION_JSON));
  System.out.println("String_Node_Str" + requestUri.toString());
  ObjectNode responseJson=null;
  try (CloseableHttpClient httpclient=HttpClients.createDefault();CloseableHttpResponse response=httpclient.execute(request);InputStream inputStream=response.getEntity().getContent()){
    int responseCode=response.getStatusLine().getStatusCode();
    String responseBody=((inputStream != null) ? IOUtils.toString(inputStream) : "String_Node_Str");
    String responseType=((response.getEntity().getContentType() != null) ? response.getEntity().getContentType().getValue() : "String_Node_Str");
    System.out.println("String_Node_Str" + requestUri.toString() + "String_Node_Str"+ responseCode);
    boolean throwServerException=false;
    if (responseCode != HttpURLConnection.HTTP_OK) {
      Application.getInstance().getGUILog().log("String_Node_Str" + responseCode);
      throwServerException=true;
    }
    if (!responseBody.isEmpty() && responseType.equals("String_Node_Str")) {
      responseJson=JacksonUtils.getObjectMapper().readValue(responseBody,ObjectNode.class);
      JsonNode value;
      if (responseJson != null && (value=responseJson.get("String_Node_Str")) != null && value.isTextual() && !value.asText().isEmpty()) {
        Application.getInstance().getGUILog().log("String_Node_Str" + value.asText());
      }
      if (responseJson != null && (value=responseJson.get("String_Node_Str")) != null && value.isArray()) {
        ArrayNode msgs=(ArrayNode)value;
        for (        JsonNode msg : msgs) {
          if (msg != null && (value=msg.get("String_Node_Str")) != null && value.isTextual() && !value.asText().isEmpty()) {
            Application.getInstance().getGUILog().log("String_Node_Str" + value.asText());
          }
        }
      }
    }
    if (throwServerException) {
      Utils.showPopupMessage("String_Node_Str");
      throw new ServerException(responseBody,responseCode);
    }
  }
   JsonNode value;
  if (responseJson != null && (value=responseJson.get("String_Node_Str")) != null && (value=value.get("String_Node_Str")) != null && value.isTextual()) {
    return value.asText();
  }
  return null;
}