I wrote an application in which I need to handle HOST_REMOVED events. I activated the Host Mobility application, but I receive
2017-06-07 21:59:13,565 | WARN | tp1493291118-324 | UiWebSocket | 158 - org.onosproject.onos-gui - 1.11.0.SNAPSHOT | Unable to parse GUI message {"event":"requestDetails","payload":{"id":"FE:82:48:57:8C:48/None","class":"host"}} due to java.lang.NullPointerException
and my application doesn't catch the event whenever I administratively kill a host using REST API. I would be grateful if you can tell me what is wrong.
This is the source code:
private void recover(HostEvent hostEvent) {
hostEvent.subject().ipAddresses().iterator().next().toInetAddress();
...
}
private class InnerHostListener implements HostListener {
#Override
public void event(HostEvent event) {
switch (event.type()) {
case HOST_ADDED:
break;
case HOST_REMOVED:
recover(event);
break;
default:
break;
}//switch
}
}
Related
I have two Debezium SQL Server connectors that have to connect to one database and publish two different tables. Their name and database.history.kafka.topic are unique. Still when adding the second one (using a POST request) I get below exceptions. I don't want to use a unique value for database.server.name which counterintuitively has been used for metric name.
java.lang.RuntimeException: Unable to register the MBean 'debezium.sql_server:type=connector-metrics,context=schema-history,server=mydatabase'
Caused by: javax.management.InstanceAlreadyExistsException: debezium.sql_server:type=connector-metrics,context=schema-history,server=mydatabase
We won't be using JMX/MBeans so it's okay to disable it, but the question is how. If there is a common way to do it for JVM please advise.
I even see below code in Debezium where it registers a MBean. Looking just at two first lines, it seems one way to bypass this issue is forcing ManagementFactory.getPlatformMBeanServer() to return null. So another way of asking the same question may be how to force ManagementFactory.getPlatformMBeanServer() return null?
public synchronized void register() {
try {
final MBeanServer mBeanServer = ManagementFactory.getPlatformMBeanServer();
if (mBeanServer == null) {
LOGGER.info("JMX not supported, bean '{}' not registered", name);
return;
}
// During connector restarts it is possible that Kafka Connect does not manage
// the lifecycle perfectly. In that case it is possible the old metric MBean is still present.
// There will be multiple attempts executed to register new MBean.
for (int attempt = 1; attempt <= REGISTRATION_RETRIES; attempt++) {
try {
mBeanServer.registerMBean(this, name);
break;
}
catch (InstanceAlreadyExistsException e) {
if (attempt < REGISTRATION_RETRIES) {
LOGGER.warn(
"Unable to register metrics as an old set with the same name exists, retrying in {} (attempt {} out of {})",
REGISTRATION_RETRY_DELAY, attempt, REGISTRATION_RETRIES);
final Metronome metronome = Metronome.sleeper(REGISTRATION_RETRY_DELAY, Clock.system());
metronome.pause();
}
else {
LOGGER.error("Failed to register metrics MBean, metrics will not be available");
}
}
}
// If the old metrics MBean is present then the connector will try to unregister it
// upon shutdown.
registered = true;
}
catch (JMException | InterruptedException e) {
throw new RuntimeException("Unable to register the MBean '" + name + "'", e);
}
}
You should use a single Debezium SQL Server connector for this, and use the table.include.list property on the connector to list the two tables you want to capture.
https://debezium.io/documentation/reference/stable/connectors/sqlserver.html#sqlserver-property-table-include-list
Intro:
I've been trying (and failing for four entire days straight so far) to get my Atmega32u4 device (Arduino Pro Micro) to emulate an Xbox controller.
It doesn't have to pretend it's an Xbox controller, but I need to communicate with the XInput driver, so emulating an official controller seemed like the best way to start.
The problem:
When using the code example XInputPadMicro by Bootsector it gets me exactly halfway. My device can either read OR write from/to the device driver. But not both. Getting both to work is essential to my project.
The code:
Device/Configuration descriptor can be found in XInputPadMicro (I
haven't changed these).
Configuration changed event:
Enabling the "OUT" endpoint will break the "IN" endpoint.
#define JOYSTICK_EPADDR_IN (ENDPOINT_DIR_IN | 1)
#define JOYSTICK_EPADDR_OUT (ENDPOINT_DIR_OUT | 1)
void EVENT_USB_Device_ConfigurationChanged(void)
{
bool ConfigSuccess = true;
ConfigSuccess &= Endpoint_ConfigureEndpoint(JOYSTICK_EPADDR_IN, EP_TYPE_INTERRUPT, 20, 1);
//If I enable this, the "IN" Endpoint will stop sending data.
//ConfigSuccess &= Endpoint_ConfigureEndpoint(JOYSTICK_EPADDR_OUT, EP_TYPE_INTERRUPT, 8, 1);
}
USB control request event:
void EVENT_USB_Device_ControlRequest(void)
{
/* Handle HID Class specific requests */
switch (USB_ControlRequest.bRequest)
{
case HID_REQ_GetReport:
if (USB_ControlRequest.bmRequestType == (REQDIR_DEVICETOHOST | REQTYPE_CLASS | REQREC_INTERFACE))
{
Endpoint_ClearSETUP();
Endpoint_Write_Control_Stream_LE(&gamepad_state, 20);
Endpoint_ClearIN();
}
break;
case HID_REQ_SetReport:
if (USB_ControlRequest.bmRequestType == (REQDIR_HOSTTODEVICE | REQTYPE_CLASS | REQREC_INTERFACE))
{
Endpoint_ClearSETUP();
Endpoint_Read_Control_Stream_LE(&RXData, 8);
Endpoint_ClearOUT();
}
break;
}
}
HID Task (called every cycle):
void HID_Task(void)
{
/* Device must be connected and configured for the task to run */
if (USB_DeviceState != DEVICE_STATE_Configured)
return;
Endpoint_SelectEndpoint(JOYSTICK_EPADDR_OUT);
if (Endpoint_IsOUTReceived())
{
toggle = !toggle;
SetLED(LED3, toggle);
Endpoint_Read_Stream_LE(&RXData, 8, NULL);
SetLED(LED1, RXData[3] > 0 || RXData[4] > 0);
Endpoint_ClearOUT();
}
/* Select the Joystick Report Endpoint */
Endpoint_SelectEndpoint(JOYSTICK_EPADDR_IN);
/* Check to see if the host is ready for another packet */
if (Endpoint_IsINReady())
{
/* Write Joystick Report Data */
Endpoint_Write_Stream_LE(&gamepad_state, 20, NULL);
/* Finalize the stream transfer to send the last packet */
Endpoint_ClearIN();
}
}
Am I missing something crucial? Perhaps about the inner workings of the USB protocol? I am at a loss here.
I'm new to jade and I have 5 agents in eclipse that have formula for finding an average and the question is how to send information from agent to this formula for calculation?
I'll be glad if someone can help me with this.
For example, there is one of my agents. There's no formula, because I don't know how to represent it. This is math expression of it: n+=alfa(y(1,2)-y(1,1))
public class FirstAgent extends Agent {
private Logger myLogger = Logger.getMyLogger(getClass().getName());
public class WaitInfoAndReplyBehaviour extends CyclicBehaviour {
public WaitInfoAndReplyBehaviour(Agent a) {
super(a);
}
public void action() {
ACLMessage msg = myAgent.receive();
if(msg != null){
ACLMessage reply = msg.createReply();
if(msg.getPerformative()== ACLMessage.REQUEST){
String content = msg.getContent();
if ((content != null) && (content.indexOf("What is your number?") != -1)){
myLogger.log(Logger.INFO, "Agent "+getLocalName()+" - Received Info Request from "+msg.getSender().getLocalName());
reply.setPerformative(ACLMessage.INFORM);
try {
reply.setContentObject(7);
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
else{
myLogger.log(Logger.INFO, "Agent "+getLocalName()+" - Unexpected request ["+content+"] received from "+msg.getSender().getLocalName());
reply.setPerformative(ACLMessage.REFUSE);
reply.setContent("( UnexpectedContent ("+content+"))");
}
}
else {
myLogger.log(Logger.INFO, "Agent "+getLocalName()+" - Unexpected message ["+ACLMessage.getPerformative(msg.getPerformative())+"] received from "+msg.getSender().getLocalName());
reply.setPerformative(ACLMessage.NOT_UNDERSTOOD);
reply.setContent("( (Unexpected-act "+ACLMessage.getPerformative(msg.getPerformative())+") )");
}
send(reply);
}
else {
block();
}
}
}
So from what I can make out you want to (1) send a formula/task to multiple platforms, (2) have them performed locally, (3) and have the results communicated back.
I think there are atleast two ways of doing this:
The first is sending an object in an ACLMessage using Java Serialisation. This is a more OOP approach and not very "Agenty".
The second being the cloning or creating a local task agent.
Using Java SerialZation. (Solution 1)
Create an object for the calculation
class CalculationTask implements serialization
{ int n;
int calculate(){
n+=alfa(y(1,2)-y(1,1));
}
}
send the calculation object via ACLMESSAGE from the senderAgent.
request.setContentObject(new CalculationTask())
recieve the calculation object by recieverAgent and perform calculation on the object. Then response setting the complete task in the response.
CalculationTask myTask = request.getContentObject();
myTask.calculate();
ACLMESSAGE response = request.createReply();
response.setContentObject(myTask());
response.setPerformative(ACLMESSAGE.INFORM)
send(response)
The senderAgent then receives the complete job.
ACLMESSAGE inform = getMessage();
CalculationTask completeTask = inform.getContentObject();
completeTask.process()
Creating local Task Agents (Solution 2)
The Agent Orientated way of doing it would be to launch a task agent on each platform. Have each task agent complete the task and respond appropriately.
i want to test if the JMS listener is working !
to do that i want to test if the Queue size do not change for more than 5 seconds that means that the listener is not working
what should i add to my code please
try {
if ((msgIdMap.contains(tm.getJMSMessageID())) || !(message instanceof TextMessage)) {
System.out.println("\tListener not working !");
} else {
process((TextMessage) message);
}
If the listener is designed, coded and configured correctly it should be working unless there's a problem with the provider. If there is a problem with the provider, the client portion of the provider should detect it and call your ExceptionListener, if it is defined.
So, I would provide an ExceptionListener, by having your class implement the ExceptionListener:
public class MyJMSClass implements javax.jms.ExceptionListener {
then set the listener on the connection to this class:
connection.setExceptionListener(this);
then provide the recovery code:
public void onException(JMSException jmse) {
log.error("JMS exception has occured.. ", jmse);
// handle exception appropriately, perhaps by attempting to reconnect
}
I'm using usbmanager class to manage USB host on my android 4.1.1 machine.
all seems to work quite well for a few hundreds of transactions until (after ~ 900 transactions) opening the device fails, returning null without exception.
Using a profiler it doesn't seem to be a matter of memory leakage.
this is how I initialize the communication from my main activity (doing this once):
public class MainTestActivity extends Activity {
private BroadcastReceiver m_UsbReceiver = null;
private PendingIntent mPermissionIntent = null;
UsbManager m_manager=null;
DeviceFactory m_factory = null;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
mPermissionIntent = PendingIntent.getBroadcast(this, 0, new Intent(ACTION_USB_PERMISSION), 0);
IntentFilter filter = new IntentFilter(ACTION_USB_PERMISSION);
filter.addAction(UsbManager.ACTION_USB_DEVICE_DETACHED);
m_UsbReceiver = new BroadcastReceiver() {
public void onReceive(Context context, Intent intent) {
String action = intent.getAction();
if (UsbManager.ACTION_USB_DEVICE_DETACHED.equals(action)) {
UsbDevice device = (UsbDevice)intent.getParcelableExtra(UsbManager.EXTRA_DEVICE);
if (device != null) {
// call your method that cleans up and closes communication with the device
Log.v("BroadcastReceiver", "Device Detached");
}
}
}
};
registerReceiver(m_UsbReceiver, filter);
m_manager = (UsbManager) getSystemService(Context.USB_SERVICE);
m_factory = new DeviceFactory(this,mPermissionIntent);
}
and this is the code of my test:
ArrayList<DeviceInterface> devList = m_factory.getDevicesList();
if ( devList.size() > 0){
DeviceInterface devIf = devList.get(0);
UsbDeviceConnection connection;
try
{
connection = m_manager.openDevice(m_device);
}
catch (Exception e)
{
return null;
}
The test will work OK for 900 to 1000 calls and after this the following call will return null (without exception):
UsbDeviceConnection connection;
try
{
connection = m_manager.openDevice(m_device);
}
You might just run out of file handles, a typical limit would be 1024 open files per process.
Try calling close() on the UsbDeviceConnection, see doc.
The UsbDeviceConnection object has allocated system ressources - e.g. a file descriptor - which will be released only on garbage collection in your code. But in this case you run out of ressources before you run out of memory - which means the garbage collector is not invoked yet.
I had opendevice fail on repeated runs on android 4.0 even though I open only once in my code. I had some exit paths that did not close the resources and I had assumed the OS would free it on process termination.
However there seems to be some issue with release of resources on process termination -I used to have issues even when I terminated and launched a fresh process.
I finally ensured release of resources on exit and made the problem go away.