RJ, sorry you're having such a frustrating time. I'm sure there's much better ways the GML I/O support could have been designed - it was done in a hurry, to meet a pretty specific use case. There may also be bugs in the codebase, which is possibly what you're running into.
However, until someone has the time & ideas to write something better, that's what we're stuck with. :-( Why don't you post a sample GML file and your template, and maybe someone (maybe even me!) will be able to figure out how to get it to work? Rahkonen Jukka wrote: > Hi, > > I believe I can be classified as a power user of number of commercial and > open source GIS software. Though I do not believe I can ever write a working > input or output template. I have tried with poor success. But perhaps it is > impossible to make it more user friendly? > The use cases I have had deal with WFS services. Usually it is possible to > get a feature type out of a WFS with a browser or wget or something even if > the server is somehow badly configured so that the real clients won't parse > the GML document. I have been dreaming of storing the bad GML on disk for > editing, and then just open the corrected GML directly with OpenJUMP. > Unfortunately I haven't been able to make a proper input template so far. > > -Jukka Rahkonen- > > > -----Alkuperäinen viesti----- > Lähettäjä: [EMAIL PROTECTED] puolesta: Martin Davis > Lähetetty: ti 29.1.2008 19:16 > Vastaanottaja: List for discussion of JPP development and use. > Aihe: Re: [JPP-Devel] Question about GML > > Here's an extract from the JUMP User Guide: > > APPENDIX: GML INPUT & OUTPUT TEMPLATES > To read a general GML file, JUMP makes use of a mapping file called a > GML input > template. This template specifies how the contents of the GML file are > mapped to a JUMP > features. Similarly, when saving a GML file, JUMP uses a GML output > template to specify > the structure of the output GML. The following sections explain how to > create GML input and > output templates. > > Note: You don't need to create input or output templates for JUMP GML > files. For more > information, see 4.1 Loading A Layer and 4.2 Saving A Layer. > > 12.1 WRITING A GML INPUT TEMPLATE > > GML Input Templates are able to extract a single FeatureCollection of > features from a GML > file. Attribute values for each feature can be extracted from the GML > describing the feature > in a variety of ways. > Listing 12-1 below shows an example of an input template (the column > definitions are > omitted and will be discussed later). > > <?xml version='1.0' encoding='UTF-8'?> > <JCSGMLInputTemplate> > <CollectionElement>dataFeatures</CollectionElement> > <FeatureElement>Feature</FeatureElement> > <GeometryElement>gml:polygonProperty</GeometryElement> > <ColumnDefinitions> > ............. > </ColumnDefinitions> > </JCSGMLInputTemplate> > > Listing 12-1 - Example of an input template (column definitions omitted) > > The input template begins by specifying the GML document's collection > element > (dataFeatures) and the feature element (Feature). This information tells > JUMP how to > identify each feature in the GML document. > Next, the geometry element and column definitions are given. These > specify the spatial > and non-spatial attributes of each feature. They specify child elements > of the feature > element (e.g. gml:polygonProperty is a child element of Feature). > If there is more than one kind of geometry element in the file (e.g. > Polygons and > MultiPolygons), you can specify multiple GeometryElement tags. Note > however that JUMP > still assumes that each feature has only one geometry. If a feature is > found to have more > than one geometry, only the last one is read. > Within the <ColumnDefinitions> tags are <column> tags, for each of the > feature's nonspatial > attributes. Listing 12-2 below shows an example of a column definition. > > <column> > <name>Rainfall</name> > <type>DOUBLE</type> > <valueelement elementname="rainfall"/> > <valuelocation position="body"/> > </column> > Listing 12-2 - Example of a column definition > > name is the name that you want the column to have in JUMP. > type may be STRING, INTEGER, DOUBLE, or DATE. (JUMP can identify and > parse a variety > of date formats, but the recommended format for your data is yyyy-mm-dd). > value-element tells JUMP how to find the XML element containing the > column value. In the > example, the element is the one named "rainfall". In some cases there > may be multiple > elements with the same name in the GML for a feature. To handle these > cases, elements > may be identified more precisely by providing a combination of the > following attributes: > > Attribute Value Optional? > element-name The name of the element N > attribute-name The name of an attribute on the element Y > attribute-value The value of the given attribute Y > value-location tells JUMP how to extract the actual value of the column > from the identified > element. In the example the value is being extracted from the body of > the element. The > template also supports specifying that the value is located as the value > of an attribute of the > element by using the attributeName attribute: > <value-location position="attribute" attributeName="average-rainfall"/> > > 12.2 WRITING A GML OUTPUT TEMPLATE > > Output templates are literally a "template" for the text in the desired > output file. They > consist of constant GML markup, together with symbols which will be > replaced by the > geometry and attribute information in a JUMP feature collection. This > allows complete > flexibility in the GML produced. (In fact, the output does not have to > be GML at all, > although the only Geometry output format currently supported is GML). > GML output templates have the following structure: > > Header Section > <%FEATURE%> > Feature-Definition Section > <%ENDFEATURE%> > Footer Section > > Listing 12-3 - Output-template structure > > The header and footer sections can contain arbitrary GML markup or data. > They will appear > at the beginning and end of the output GML file. They contain the > opening and closing > markup for the GML file elements as well as any elements which open and > close the GML > FeatureCollection. > The Feature-Definition Section can contain arbitrary GML markup, as well > special output > template tags. In the output GML the template tags will be replaced by > the actual data for > the geometry and attributes of a JUMP feature collection. The > Feature-Definition Section > will be repeated once for each feature in the JUMP feature collection. > The supported output > template tags are given below. > > Table 12-1 - Special output-template tags > > TAG DESCRIPTION > <%=COLUMN columnname%> Inserts the value of the attribute named columnname. > <%=GEOMETRY%> Inserts a GML representation of the geometry. > > An example of an output template is given in Listing 12-4 below. > > <?xml version='1.0' encoding='UTF-8'?> > <dataset> > <%FEATURE%> > <Feature> > <property name="FID"><%=COLUMN fid%></property> > <property name="DESCRIPTION"> > <%=COLUMN description%> > </property> > <GEOMETRY> > <%=GEOMETRY%> > </GEOMETRY > > </Feature> > <%ENDFEATURE%> > </dataset> > Listing 12-4 - Example of an output template > > Note: If you open a GML or FME GML file then save it again in the same > format, some > information may be lost. The Workbench preserves only the information it > uses: > · one spatial attribute for each feature (the "geometry") > · some non-spatial attributes for each feature (strings, dates and numbers) > Any information that the Workbench does not use will not be present in > the document that > gets saved. Therefore, you should generally avoid using the Workbench to > overwrite > existing files, unless you are sure that you won't need all of the > information in the old file. > > Giuseppe Aruta wrote: > >> Some days ago I recived an e-mail from Alice, a studend of Verona who >> is studing GML specification. She wanted to know how she can write >> template to read/write GML files in OpenJUMP. >> She also write a letter to OpenJUMP Users List. I post her letter to >> the Developer list. >> If some developers know how and can explain it , this would be a >> benefit for everybody . I also have difficult to understand Jump User >> manual on how to use GML files. >> The best, useful answer willl be used as wiki page on OJ documentation >> Best Regards >> Peppe >> _____________________________ >> Hi, my name is Alice Falchi and I'm an italian student in informatics >> at University of Verona (Italy). I'm doing an analysis of available >> softwares to visualization GML file. >> One of these is exactly Jump. >> By my research I realized that now the GML standard isn't well defined >> yet. Infact I'm not able to run any GML files. >> Please, can you help me to understand how to build correctly GML >> files? Which features with? And finally, how I create "input template"? >> Thanks! >> >> ------------------------------------------------------------------------ >> ------------------------------------------------------------------------ >> L'email della prossima generazione? Puoi averla con la nuova Yahoo! >> Mail >> <http://us.rd.yahoo.com/mail/it/taglines/hotmail/nowyoucan/nextgen/*http://it.docs.yahoo.com/nowyoucan.html> >> >> >> >> ------------------------------------------------------------------------ >> >> ------------------------------------------------------------------------- >> This SF.net email is sponsored by: Microsoft >> Defy all challenges. Microsoft(R) Visual Studio 2008. >> http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ >> >> ------------------------------------------------------------------------ >> >> _______________________________________________ >> Jump-pilot-devel mailing list >> Jump-pilot-devel@lists.sourceforge.net >> https://lists.sourceforge.net/lists/listinfo/jump-pilot-devel >> > > -- Martin Davis Senior Technical Architect Refractions Research, Inc. (250) 383-3022 ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. 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