/*
* Copyright (C) 2007 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package android.location;
import com.android.internal.location.ProviderProperties;
/**
* An abstract superclass for location providers. A location provider
* provides periodic reports on the geographical location of the
* device.
*
* <p> Each provider has a set of criteria under which it may be used;
* for example, some providers require GPS hardware and visibility to
* a number of satellites; others require the use of the cellular
* radio, or access to a specific carrier's network, or to the
* internet. They may also have different battery consumption
* characteristics or monetary costs to the user. The {@link
* Criteria} class allows providers to be selected based on
* user-specified criteria.
*/
public class LocationProvider {
public static final int OUT_OF_SERVICE = 0;
public static final int TEMPORARILY_UNAVAILABLE = 1;
public static final int AVAILABLE = 2;
/**
* A regular expression matching characters that may not appear
* in the name of a LocationProvider
* @hide
*/
public static final String BAD_CHARS_REGEX = "[^a-zA-Z0-9]";
private final String mName;
private final ProviderProperties mProperties;
/**
* Constructs a LocationProvider with the given name. Provider names must
* consist only of the characters [a-zA-Z0-9].
*
* @throws IllegalArgumentException if name contains an illegal character
*
* @hide
*/
public LocationProvider(String name, ProviderProperties properties) {
if (name.matches(BAD_CHARS_REGEX)) {
throw new IllegalArgumentException("provider name contains illegal character: " + name);
}
mName = name;
mProperties = properties;
}
/**
* Returns the name of this provider.
*/
public String getName() {
return mName;
}
/**
* Returns true if this provider meets the given criteria,
* false otherwise.
*/
public boolean meetsCriteria(Criteria criteria) {
return propertiesMeetCriteria(mName, mProperties, criteria);
}
/**
* @hide
*/
public static boolean propertiesMeetCriteria(String name, ProviderProperties properties,
Criteria criteria) {
if (LocationManager.PASSIVE_PROVIDER.equals(name)) {
// passive provider never matches
return false;
}
if (properties == null) {
// unfortunately this can happen for provider in remote services
// that have not finished binding yet
return false;
}
if (criteria.getAccuracy() != Criteria.NO_REQUIREMENT &&
criteria.getAccuracy() < properties.mAccuracy) {
return false;
}
if (criteria.getPowerRequirement() != Criteria.NO_REQUIREMENT &&
criteria.getPowerRequirement() < properties.mPowerRequirement) {
return false;
}
if (criteria.isAltitudeRequired() && !properties.mSupportsAltitude) {
return false;
}
if (criteria.isSpeedRequired() && !properties.mSupportsSpeed) {
return false;
}
if (criteria.isBearingRequired() && !properties.mSupportsBearing) {
return false;
}
if (!criteria.isCostAllowed() && properties.mHasMonetaryCost) {
return false;
}
return true;
}
/**
* Returns true if the provider requires access to a
* data network (e.g., the Internet), false otherwise.
*/
public boolean requiresNetwork() {
return mProperties.mRequiresNetwork;
}
/**
* Returns true if the provider requires access to a
* satellite-based positioning system (e.g., GPS), false
* otherwise.
*/
public boolean requiresSatellite() {
return mProperties.mRequiresSatellite;
}
/**
* Returns true if the provider requires access to an appropriate
* cellular network (e.g., to make use of cell tower IDs), false
* otherwise.
*/
public boolean requiresCell() {
return mProperties.mRequiresCell;
}
/**
* Returns true if the use of this provider may result in a
* monetary charge to the user, false if use is free. It is up to
* each provider to give accurate information.
*/
public boolean hasMonetaryCost() {
return mProperties.mHasMonetaryCost;
}
/**
* Returns true if the provider is able to provide altitude
* information, false otherwise. A provider that reports altitude
* under most circumstances but may occassionally not report it
* should return true.
*/
public boolean supportsAltitude() {
return mProperties.mSupportsAltitude;
}
/**
* Returns true if the provider is able to provide speed
* information, false otherwise. A provider that reports speed
* under most circumstances but may occassionally not report it
* should return true.
*/
public boolean supportsSpeed() {
return mProperties.mSupportsSpeed;
}
/**
* Returns true if the provider is able to provide bearing
* information, false otherwise. A provider that reports bearing
* under most circumstances but may occassionally not report it
* should return true.
*/
public boolean supportsBearing() {
return mProperties.mSupportsBearing;
}
/**
* Returns the power requirement for this provider.
*
* @return the power requirement for this provider, as one of the
* constants Criteria.POWER_REQUIREMENT_*.
*/
public int getPowerRequirement() {
return mProperties.mPowerRequirement;
}
/**
* Returns a constant describing horizontal accuracy of this provider.
* If the provider returns finer grain or exact location,
* {@link Criteria#ACCURACY_FINE} is returned, otherwise if the
* location is only approximate then {@link Criteria#ACCURACY_COARSE}
* is returned.
*/
public int getAccuracy() {
return mProperties.mAccuracy;
}
}