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A LocationProvider represents a location-providing module, generating Locations. Applications obtain LocationProvider instances classes implementing the actual functionality by extending this abstract class by calling the factory method.

It is the responsibility of the implementation to return the correct LocationProvider-derived object. Applications that need to specify criteria for the location provider selection, must first create a Criteria object, and pass it to the factory method. The methods that access the location related information shall throw SecurityException if the application does not have the relevant permission to access the location information.

If an application invokes LocationProvider. Constructor Summary protected LocationProvider Empty constructor to help implementations and extensions. Method Summary static void addProximityListener ProximityListener listener, Coordinates coordinates, float proximityRadius Adds a ProximityListener for updates when proximity to the specified coordinates is detected.

Methods inherited from class java. Temporary unavailability means that the method is unavailable due to reasons that can be expected to possibly change in the future and the provider to become available. An example is not being able to receive the signal because the signal used by the location method is currently being obstructed, e.

Permanent unavailability means that the method is unavailable and the implementation is not able to expect that this situation would change in the near future. An example is when using a location method implemented in an external device and the external device is detached. This is not intended to be used by applications.

Applications should not make subclasses of this class and invoke this constructor from the subclass. The return value shall be one of the availability status code constants defined in this class. The implementation chooses the LocationProvider so that it best fits the defined criteria, taking into account also possible implementation dependent preferences of the end user.

If no concrete LocationProvider could be created that typically can match the defined criteria but there are other location providers not meeting the criteria that could be returned for a more relaxed criteria, null is returned to indicate this. The LocationException is thrown, if all supported location providers are out of service.

If the current location is known to be within the proximity radius of the specified coordinates, the listener shall be called immediately. Detecting the proximity to the defined coordinates is done on a best effort basis by the implementation.

Due to the limitations of the methods used to implement this, there are no guarantees that the proximity is always detected; especially in situations where the terminal briefly enters the proximity area and exits it shortly afterwards, it is possible that the implementation misses this.

It is optional to provide this feature as it may not be reasonably implementable with all methods used to implement this API. If the implementation is capable of supporting the proximity monitoring and has resources to add the new listener and coordinates to be monitored but the monitoring can't be currently done due to the current state of the method used to implement it, this method shall succeeed and the monitoringStateChanged method of the listener shall be immediately called to notify that the monitoring is not active currently.

NaN NullPointerException - if the listener or coordinates parameter is null SecurityException - if the application does not have the permission to register a proximity listener Since: JDE 4. The implementation chooses the LocationProvider so that it best fits the defined criteria, taking into account also possible implementation dependent preferences of the end user.

If no concrete LocationProvider could be created that typically can match the defined criteria but there are other location providers not meeting the criteria that could be returned for a more relaxed criteria, null is returned to indicate this. The LocationException is thrown, if all supported location providers are out of service.

A LocationProvider instance is returned if there is a location provider meeting the criteria in either the available or temporarily unavailable state. Implementations should try to select providers in the available state before providers in temporarily unavailable state, but this can't be always guaranteed because the implementation may not always know the state correctly at this point in time.

If a LocationProvider meeting the criteria can be supported but is currently out of service, it shall not be returned. When this method is called with a Criteria that has all fields set to the default values i. Passing null as the parameter is equal to passing a Criteria that has all fields set to the default values, i. This method only makes the selection of the provider based on the criteria and is intended to return it quickly to the application.

This method may, depending on the implementation, return the same LocationProvider instance as has been returned previously from this method to the calling application, if the same instance can be used to fulfil both defined criteria. Note that there can be only one LocationListener associated with a LocationProvider instance. Parameters: criteria - the criteria for provider selection or null if the default provider is requested Returns: a LocationProvider meeting the defined criteria or null if a LocationProvider that meets the defined criteria can't be returned but there are other supported available or temporarily unavailable providers that do not meet the criteria.

Sign up or log in Sign up using Google. Sign up using Facebook. Sign up using Email and Password. Post as a guest Name. Email Required, but never shown. The Overflow Blog. Podcast Making Agile work for data science. Stack Gives Back Featured on Meta. When System. The following piece of code illustrates how to obtain the current location of the terminal. This piece of code illustrates obtaining the location syncronously. An application would normally perform this within a separate thread, because the getLocation method may block for a long time.

The following example illustrates how to use the LocationListener for subscribing to periodic location updates. This example creates a handler thread to handle the updates so that the methods on the listener would not block the platform implementation threads for a long time. The LocationListener represents a listener that receives events associated with a particular LocationProvider. This interface represents a listener to events associated with detecting proximity to some registered coordinates.

The Coordinates class represents coordinates as latitude-longitude-altitude values. The criteria used for the selection of the location provider is defined by the values in this class. The LandmarkStore class provides methods to store, delete and retrieve landmarks from a persistent landmark store. This is the starting point for applications using this API and represents a source of the location information. The QualifiedCoordinates class represents coordinates as latitude-longitude-altitude values that are associated with an accuracy value.