{{Short description, Physical location application interface The Location API for Java ME is a compact and generic Java 2 ME API that produces information about the device's present physical location to Java applications. This API can be optionally supported by mobile phone and

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manufacturers, with the minimum Java platform required for this API being CLDC v1.1. The Location API was developed under the Java Community Process as JSR 179, released in September 2003 and updated to version 1.0.1 in March 2006. Nokia is the main author and maintainer of this JSR. OpenLAPI is an

LGPL The GNU Lesser General Public License (LGPL) is a free-software license published by the Free Software Foundation (FSF). The license allows developers and companies to use and integrate a software component released under the LGPL into their own ...

implementation for use in emulator environments where the Nokia reference implementation does not exist and for devices which can access a

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device over Bluetooth.

Features

The Location API is designed to work with many different positioning methods. Generic interfaces lets application developers implement systems that can retrieve location data from multiple sources, based on their availability on the device. It has advantages over a single means of tracking, including fail-over, indoor/outdoor transparency, and a choice between the speed and accuracy trade-offs between

, cellular, or other positioning methods. The API supports: *Current location - current latitude, longitude, altitude, direction, and speed of the phone, and methods to convert it to text. *Landmark proximity - a store of landmarks can be stored on the phone's memory, and the current location can be added as a landmark. *Address data - the nearest landmark's textual details, such as postal address, phone number, country, and the building and its URL.Dr. Dobb's 2006 - The Java Location API - Address Information
/ref> *Location listeners - for dynamic location-based applications that will be triggered by when the current location changes. The Location API does not support: *Topological data - which is usually derived from the shapes of cell site coverage. *Location-based queries - although the current location of the device can be calculated.

Device independence

Previously, location service implementations were provider specific. The aim of this API was to provide a common API for retrieving the location information on a variety of devices. OpenLAPI supports several back-ends: * GPS over Bluetooth * NMEA logfile (for development) * KML (

Keyhole Markup Language Keyhole Markup Language (KML) is an XML notation for expressing geographic annotation and visualization within two-dimensional maps and three-dimensional Earth browsers. KML was developed for use with Google Earth, which was originally named Key ...

) (for development) * random entry from a persistent landmark store (for development) along with device specific wrappers.

Support

Since many providers choose not to implement this optional JSR, the goal of universality has still not happened and developers are often required to create custom builds for different devices. The Location API is available to Java applications on some BlackBerry and Windows Mobile devices, recent Motorola and Sony Ericsson devices, and all Nokia Series 60 3rd Edition devices.

References

External links

JSR 179 Location API for J2ME
Java device platform Java specification requests Keyhole Markup Language Java APIs