edu.wisc.ssec.mcidas.adde
Class AddeURLConnection

java.lang.Object
  extended by java.net.URLConnection
      extended by edu.wisc.ssec.mcidas.adde.AddeURLConnection

public class AddeURLConnection
extends java.net.URLConnection

This class extends URLConnection, providing the guts of the work to establish an ADDE network connection, put together a request packet, and initiate data flow. Connections for image data, image directories, grid data, grid directory, point source data and dataset information (McIDAS AGET, ADIR, GDIR, GGET, MDKS, TXTG and LWPR requests) are supported.

See Also:
McIDAS Programmer's Manual

 URLs must all have the following format:

   adde://host/request?keyword_1=value_1&keyword_2=value_2

 where request can be one of the following:

   datasetinfo - request for data set information (LWPR)
   griddirectory - request for grid directory information (GDIR)
   griddata - request for grid data (GGET)
   imagedata - request for data in AreaFile format (AGET)
   imagedirectory - request for image directory information (ADIR)
   pointdata - request for point data (MDKS)
   textdata - request to read a text file (TXTG) 

 There can be any valid combination of the following supported keywords:

 -------for any request

   group=         ADDE group name
   user=            ADDE user identification
   proj=             a valid ADDE project number
   trace=<0/1>               setting to 1 tells server to write debug 
                               trace file (imagedata, imagedirectory)
   version=                  ADDE version number, currently 1 except for
                             griddata requests
   debug=                    set to true to watch the printlns stream by
   compress=                 set to true if you want to use compressed
                             transfers.  You need to have the VisAD package
                             if you want to support this.

 -------for images:

   descr=        ADDE descriptor name
   band=               spectral band or channel number 
   mag=          image magnification, postitive for blowup, 
                               negative for blowdown (default = 1, emag=lmag)
                               (imagedata only)
   latlon=         lat/lon point to center image on (imagedata only)
   linele=   line/element to center image on (imagedata only)
   place=         placement of lat/lon or linele points (center 
                               or upperleft (def=center)) (imagedata only)
   pos=            request an absolute or relative ADDE position 
                               number
   size=    size of image to be returned (imagedata only)
   unit=               to specify calibration units other than the 
                               default 
   spac=              number of bytes per data point, 1, 2, or 4 
                               (imagedata only)
   doc=              specify yes to include line documentation 
                               with image (def=no) 
   aux=              specify yes to include auxilliary information 
                               with image 
   time=       specify the time range of images to select
                               (def=latest image if pos not specified)
   day=                 specify the day of the images to select
                               (def=latest image if pos not specified)
   cal=            request a specific calibration on the image 
                               (imagedata only)
   id=               radar station id 

 ------ for grids:

   descr=        ADDE descriptor name
   param=        parameter code list
   time=     time in hhmmss format
   day=       day in ccyyddd format
   lev=          list of requested levels (value or SFC, MSL 
                               or TRO)
   ftime=     valid time (hhmmss format) (use with fday)
   fday=       forecast day (ccyyddd)
   fhour=    forecast hours (offset from model run time)
                                (hhmmss format)
   num=                 maximum number of grids to return (nn)

 ------ for point data:

   descr=        ADDE descriptor name
   pos=            request an absolute or relative ADDE 
                               position number
   select=