System Introspection for System Analysis on Mobile Devices

tends the JPanel class. The template is used to define a skeleton <strong>for</strong> concretecomponent panels. Each component tab must extend the PanelTemplate andis <strong>for</strong>ced to implement the update() method <strong>for</strong> observation. Each panel isadded to the observers of the communication interface. To present the dataeach panel can create its own layout.LogPanelThe LogPanel is implemented <strong>for</strong> the creation of logging cycles on the probe.This panel requests the list of available logging components from the probe.The received list is presented by check-boxes <strong>for</strong> each logging component.When the logging cycle is executed, the LogPanel sends the list of selectedlogging components to the probe and inactivates all elements of the view exceptthe stop button. When the logging cycle is requested to stop, the stopcommand is send to the probe and the elements of the LogPanel are activatedagain. Like the mobile client changing the current tab while a logging cycle isactive does not result in stopping the logging cycle.The Helper PanelsTo present the state of the probe, the Java client offers several helper panels.Each panel observes the communication interface <strong>for</strong> corresponding in<strong>for</strong>mation.Implemented panels are the BeaconPanel, ErrorPanel, StatusPaneland the ComponentPanel.BeaconPanelThe Beaconpanel presents the data of the last beacon received from the server.It extracts the properties of the received beacon and fills them to correspondinglabels.ComponentPanelThe ComponentPanel uses a timer to request the state of the componentthreads with a given frequency. When the list is received it is parsed andprinted to a label.ErrorPanelTo show errors received from the probe the ErrorPanel listens to the communicationinterface <strong>for</strong> incoming messages containing errors. Once an errormessage is received it is parsed and displayed.52