How to use

Service

in

edu.wpi.rail.jrosbridge

private String getMethodType(Ros ros, String topic) {
  Service addTwoInts = new Service(ros, "/rosapi/topic_type", "rosapi/TopicType");
  ServiceRequest request = new ServiceRequest("{\"topic\": \""+ topic +"\"}");
  ServiceResponse response = addTwoInts.callServiceAndWait(request);
  JSONObject ob = new JSONObject(response.toString());
  return ob.getString("type");
}

/**
 * Call the service and wait for a response. This is a blocking call and
 * will only return once rosbridge returns the service response. For an
 * asynchronous version of this call, see the
 * {@link #callService(ServiceRequest request, ServiceCallback cb)
 * callService} method.
 * 
 * @param request
 *            The service request to send.
 * @return The corresponding service response from ROS.
 */
public synchronized ServiceResponse callServiceAndWait(
    ServiceRequest request) {
  // private inner class to use as a callback
  BlockingCallback cb = new BlockingCallback(this);
  // use the asynchronous version and block on the result
  this.callService(request, cb);
  // wait for a response
  while (cb.getResponse() == null) {
    try {
      this.wait();
    } catch (InterruptedException e) {
      // continue on
    }
  }
  return cb.getResponse();
}

/**
 * Call the service and wait for a response. This is a blocking call and
 * will only return once rosbridge returns the service response. For an
 * asynchronous version of this call, see the
 * {@link #callService(ServiceRequest request, ServiceCallback cb)
 * callService} method.
 * 
 * @param request
 *            The service request to send.
 * @return The corresponding service response from ROS.
 */
public synchronized ServiceResponse callServiceAndWait(
    ServiceRequest request) {
  // private inner class to use as a callback
  BlockingCallback cb = new BlockingCallback(this);
  // use the asynchronous version and block on the result
  this.callService(request, cb);
  // wait for a response
  while (cb.getResponse() == null) {
    try {
      this.wait();
    } catch (InterruptedException e) {
      // continue on
    }
  }
  return cb.getResponse();
}