org.eclipse.kura.status

Interface CloudConnectionStatusService

@ProviderType
public interface CloudConnectionStatusService

The CloudConnectionStatusService is responsible for updating the user on the connection status of the framework. Default implementation will link the status to a LED or to the log file.
The service stores an internal list of CloudConnectionStatusComponent which represents all the elements that are responsible of notifying the connection status.

Each CloudConnectionStatusComponent is assigned with a priority and a status ( CloudConnectionStatusEnum). The Service shows the status of the highest priority CloudConnectionStatusComponent registered in the list.

In order to use the service, a class must implement the CloudConnectionStatusComponent interface and register itself in the Service component registry using the register(CloudConnectionStatusComponent c) method.

Unregistering the class from the Service registry will trigger a status switch to the previous priority found in the Service component registry.

A call to updateStatus(...) will trigger an internal status change for the relevant component, and the Service will trigger a status change for the highest priority component only if needed.

Default implementation

The default implementation is a Factory Component. A new instance of a CloudConnectionStatusService will be instantiated for each communication stack. The default CloudConnectionStatusService will have its kura.service.pid equals to org.eclipse.kura.status.CloudConnectionStatusService
Subsequent Communication Stacks will instantiate a relevant CloudConnectionStatusService with the appropriate postfix.
e.g. The CloudConnectionStatusService for a Communication Stack generated by a org.eclipse.kura.cloud.CloudService-foo will have its kura.service.pid equals to org.eclipse.kura.status.CloudConnectionStatusService-foo

Configuration for a specific CloudConnectionStatusService can be found in the kura.properties file.
The configuration is defined by a key value pair, where key is a URL-like string defining the service, and value is the entity responsible to show the Cloud Connection Status. It can be either a LED, the system log or none. Configuration for specific instances of the CloudConnectionStatusService is achieved by correctly formatting the URL-like key.
The default configuration is stored under the key ccs.status.notification.url
Configuration for specific communication stacks include the stack postfix in the URL-like key.

e.g. The key-value pair to link the CloudConnectionStatusService generated for the "foo" stack (see above) to LED number 25 would be:
ccs.status.notification.url.foo=ccs:led:25
Same configuration, but linking the status to the system log, would be:
ccs.status.notification.url.foo=ccs:log

Field Summary

Fields

Modifier and Type	Field and Description
static int	PRIORITY_CRITICAL Priorities are evaluated in ascending order.
static int	PRIORITY_HIGH
static int	PRIORITY_LOW
static int	PRIORITY_MAX Maximum priority for the notification.
static int	PRIORITY_MEDIUM
static int	PRIORITY_MIN Minimum priority for the notification.

Method Summary

Modifier and Type	Method and Description
void	register(CloudConnectionStatusComponent component) Registers a CloudConnectionStatusComponent in the component registry of the Service
void	unregister(CloudConnectionStatusComponent component) Unregisters a CloudConnectionStatusComponent from the component registry of the Service
boolean	updateStatus(CloudConnectionStatusComponent component, CloudConnectionStatusEnum status) Updates the status of a CloudConnectionStatusComponent in the registry.

Field Detail

PRIORITY_MAX

static final int PRIORITY_MAX

Maximum priority for the notification. There should be only one StatusDisplayComponent at the same time using this priority.

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Constant Field Values

PRIORITY_CRITICAL

static final int PRIORITY_CRITICAL

Priorities are evaluated in ascending order. The Service will use the status of the registered component with highest priority

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Constant Field Values

PRIORITY_HIGH

static final int PRIORITY_HIGH

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Constant Field Values

PRIORITY_MEDIUM

static final int PRIORITY_MEDIUM

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Constant Field Values

PRIORITY_LOW

static final int PRIORITY_LOW

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Constant Field Values

PRIORITY_MIN

static final int PRIORITY_MIN

Minimum priority for the notification. There should be at least and only one StatusDisplayComponent at the same time using this priority.

See Also:

Constant Field Values

Method Detail

register

void register(CloudConnectionStatusComponent component)

Registers a CloudConnectionStatusComponent in the component registry of the Service

Parameters:

component - CloudConnectionStatusComponent to be registered in the registry

unregister

void unregister(CloudConnectionStatusComponent component)

Unregisters a CloudConnectionStatusComponent from the component registry of the Service

Parameters:

component - CloudConnectionStatusComponent to be unregistered from the registry

updateStatus

boolean updateStatus(CloudConnectionStatusComponent component,
                     CloudConnectionStatusEnum status)

Updates the status of a CloudConnectionStatusComponent in the registry. Implementation should also set the internal status of the CloudConnectionStatus component so to persist it.

Parameters:

component - CloudConnectionStatusComponent for which the status has to be changed

status - CloudConnectionStatusEnum representing the new status of the component

Returns:

false if an error occurs, true otherwise