org.apache.directory.server.dns.io.encoder
Class LocationRecordEncoder

java.lang.Object
  extended by org.apache.directory.server.dns.io.encoder.LocationRecordEncoder

public class LocationRecordEncoder
extends java.lang.Object

2. RDATA Format MSB LSB +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ 0| VERSION | SIZE | +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ 2| HORIZ PRE | VERT PRE | +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ 4| LATITUDE | +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ 6| LATITUDE | +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ 8| LONGITUDE | +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ 10| LONGITUDE | +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ 12| ALTITUDE | +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ 14| ALTITUDE | +--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+--+ (octet) where: VERSION Version number of the representation. This must be zero. Implementations are required to check this field and make no assumptions about the format of unrecognized versions. SIZE The diameter of a sphere enclosing the described entity, in centimeters, expressed as a pair of four-bit unsigned integers, each ranging from zero to nine, with the most significant four bits representing the base and the second number representing the power of ten by which to multiply the base. This allows sizes from 0e0 (<1cm) to 9e9 (90,000km) to be expressed. This representation was chosen such that the hexadecimal representation can be read by eye; 0x15 = 1e5. Four-bit values greater than 9 are undefined, as are values with a base of zero and a non-zero exponent. Since 20000000m (represented by the value 0x29) is greater than the equatorial diameter of the WGS 84 ellipsoid (12756274m), it is therefore suitable for use as a "worldwide" size. HORIZ PRE The horizontal precision of the data, in centimeters, expressed using the same representation as SIZE. This is the diameter of the horizontal "circle of error", rather than a "plus or minus" value. (This was chosen to match the interpretation of SIZE; to get a "plus or minus" value, divide by 2.) VERT PRE The vertical precision of the data, in centimeters, expressed using the sane representation as for SIZE. This is the total potential vertical error, rather than a "plus or minus" value. (This was chosen to match the interpretation of SIZE; to get a "plus or minus" value, divide by 2.) Note that if altitude above or below sea level is used as an approximation for altitude relative to the [WGS 84] ellipsoid, the precision value should be adjusted. LATITUDE The latitude of the center of the sphere described by the SIZE field, expressed as a 32-bit integer, most significant octet first (network standard byte order), in thousandths of a second of arc. 2^31 represents the equator; numbers above that are north latitude. LONGITUDE The longitude of the center of the sphere described by the SIZE field, expressed as a 32-bit integer, most significant octet first (network standard byte order), in thousandths of a second of arc, rounded away from the prime meridian. 2^31 represents the prime meridian; numbers above that are east longitude. ALTITUDE The altitude of the center of the sphere described by the SIZE field, expressed as a 32-bit integer, most significant octet first (network standard byte order), in centimeters, from a base of 100,000m below the [WGS 84] reference spheroid used by GPS (semimajor axis a=6378137.0, reciprocal flattening rf=298.257223563). Altitude above (or below) sea level may be used as an approximation of altitude relative to the the [WGS 84] spheroid, though due to the Earth's surface not being a perfect spheroid, there will be differences. (For example, the geoid (which sea level approximates) for the continental US ranges from 10 meters to 50 meters below the [WGS 84] spheroid. Adjustments to ALTITUDE and/or VERT PRE will be necessary in most cases. The Defense Mapping Agency publishes geoid height values relative to the [WGS 84] ellipsoid.


Constructor Summary
LocationRecordEncoder()
           
 
Method Summary
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

LocationRecordEncoder

public LocationRecordEncoder()


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