PSVI ramblings

[Thomas Cox]

Title: Message

I have to use org.apache.xerces.impl.xs.psvi.* pretty heavily in production software, and I just wanted to post some musings and perhaps a wistful question.   The PSVI APIs seem to be fairly crufty. (Please don't take this as a rant. OK, maybe a friendly rant... ;-) Of course, having spent far too much dealing with the XML Schema spec, I have a great deal of sympathy for why that is the case. I also understand it's in the "impl" set of packages, with limited support, but it's the only game in town. (For me anyway - I don't know if it's better or not, but I can't use http://www.eclipse.org/xsd/ due to licensing issues.)   Here's my "do-it-yourself" analogy:  Let's say I need a left-handed metric wing-nut. I know I've probably got one in a Mason jar in the garage, so I put down my tools, go out, dump the jar on my workbench, poke through it until I finally find what I need, rake the parts back into the jar, and go back to work.   That's what PSVI feel like to me. It's especially poignant when I'm staring at the data I need in the debugger but it takes an extra hour to figure out all the API hooks to look it up. It's not that big an issue if you only use it occasionally, but it's not so great for frequent use. (Mind you, I'm VERY thankful I don't have to make a left-handed metric wing-net from scratch. ;-)   Here's an example: I'm traipsing through a schema, and want to find out if this element has an associated enumeration. I've already looked up the type def, so I call -       static private ArrayList getEnumFacet(XSTypeDefinition xstd)     {         ArrayList enum = null;         if (xstd != null && xstd instanceof XSSimpleTypeDefinition)         {             XSSimpleTypeDefinition xsstd = (XSSimpleTypeDefinition)xstd;             XSObjectList xsol = xsstd.getMultiValueFacets();             if (xsol != null)             {                 for (int f = 0; f < xsol.getLength(); ++f)                 {                     XSObject xob = xsol.item(f);                     if (xob instanceof XSMultiValueFacet)                     {                         XSMultiValueFacet xsmvf = (XSMultiValueFacet)xob;                         if (xsmvf.getFacetKind() == XSSimpleTypeDefinition.FACET_ENUMERATION)                         {                             enum = new ArrayList();                             StringList vals = xsmvf.getLexicalFacetValues();                             for (int v = 0; v < vals.getLength(); ++v)                             {                                 enum.add(vals.item(v));                             }                         }                     }                 }             }         }         return enum;     }   Well, OK; I got my enumeration back, so I'm fairly happy, but then I have to write a helper like that for every facet I care about. (More casting than a bass-fishing tournament. ;-) Just adding a few dozen helper functions in the right places might be enough.   The doc isn't always a big help here, either. For example see http://xml.apache.org/xerces2-j/javadocs/xerces2/index.html   ++++   Interface XSMultiValueFacet    ... getFacetKind public short getFacetKind() Returns: The name of the facet: e.i. enumeration, or pattern.   ----   LOL... OK, I've had days like that too, but could this get this fixed? Just making it "Returns: a short indicating the facet type: i.e. XSSimpleTypeDefinition.FACET_ENUMERATION or XSSimpleTypeDefinition.FACET_PATTERN."  would be helpful.     So, the big question: can we look for improvements in PSVI anytime soon?   Thanks, Thomas Cox