Package eu.h2020.helios_social.core.context

Class Context

java.lang.Object

eu.h2020.helios_social.core.context.Context

Direct Known Subclasses:

ActivityContext, ContextAnd, ContextNot, ContextOr, LocationContext, TimeContext, WifiContext

public class Context
extends java.lang.Object

This is the base class for HELIOS contexts. This class provides base methods for context implementations. A context includes a type, a state (active or inactive) and possible several attributes that are used to define and detect the context. Values of context attributes may be determined explicitly (e.g. a given static value) or implicitly (e.g. by an external context source, sensor value). To listen the changes in the active value of a context, context listeners (see the ContextListener interface) can be registered for the context. New context types can be created by extending this class.

Constructor Summary

Constructors

Constructor	Description
Context(java.lang.String name, boolean active)	Creates a context
Context(java.lang.String id, java.lang.String name, boolean active)	Creates a context

Method Summary

Modifier and Type	Method	Description
void	addSensor(Sensor sensor)	Relates a sensor input to the context.
void	addSensors(java.util.List<Sensor> sensors)	Relates a list of sensors to the context.
java.util.Iterator<ContextListener>	getContextListeners()	Gets all the listeners related to this context
java.lang.String	getId()	Gets identifier of this context
java.lang.String	getName()	Gets name of this context
java.util.Iterator<Sensor>	getSensors()	Gets sensors
boolean	isActive()	Is context active?
void	registerContextListener(ContextListener listener)	Registers a listener (ContextListener) for this context.
void	removeSensor(Sensor sensor)	Removes a sensor from the context
void	setActive(boolean active)	Sets context active value
void	setName(java.lang.String name)	Sets context name
void	unregisterContextListener(ContextListener listener)	Unregisters a ContextListener.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

Context

public Context(java.lang.String id,
               java.lang.String name,
               boolean active)

Creates a context

Parameters:

id - the identifier of this context.

name - the name of this context

active - is this context active

Context

public Context(java.lang.String name,
               boolean active)

Creates a context

Parameters:

name - the name of this context

active - is this context active

Method Detail

getId

public final java.lang.String getId()

Gets identifier of this context

Returns:

the identifier of this context

isActive

public boolean isActive()

Is context active?

Returns:

active the active value(boolean)

getName

public java.lang.String getName()

Gets name of this context

Returns:

name the name of this context

setName

public void setName(java.lang.String name)

Sets context name

Parameters:

name - the name of this context

setActive

public void setActive(boolean active)

Sets context active value

Parameters:

active - the active value

addSensor

public void addSensor(@NonNull
                      Sensor sensor)

Relates a sensor input to the context.

Parameters:

sensor - the sensor

addSensors

public void addSensors(java.util.List<Sensor> sensors)

Relates a list of sensors to the context.

Parameters:

sensors - the sensor list

removeSensor

public void removeSensor(@NonNull
                         Sensor sensor)

Removes a sensor from the context

Parameters:

sensor - the sensor

getSensors

public java.util.Iterator<Sensor> getSensors()

Gets sensors

Returns:

the sensors

registerContextListener

public void registerContextListener(ContextListener listener)

Registers a listener (ContextListener) for this context. The ContextListener will then receive changes in the context active value.

Parameters:

listener - the ContextListener

unregisterContextListener

public void unregisterContextListener(ContextListener listener)

Unregisters a ContextListener.

Parameters:

listener - the ContextListener

getContextListeners

public java.util.Iterator<ContextListener> getContextListeners()

Gets all the listeners related to this context

Returns:

the listeners