Re: [JBoss-dev] XML config files, whitespace and CDATA... and JAXB
Did you ever look into this more? --jason On Thu, 9 Aug 2001, David Jencks wrote: On 2001.08.09 17:30:51 -0400 Toby Allsopp wrote: On Wed, Aug 08, 2001 at 11:30:39PM -0400, David Jencks wrote: At the risk of changing the subject ;-) There seem to be two xml-configuration parsing systems in use. The older stuff like for ejb-jar uses code that partially validates the xml while setting properties, whereas the rar deployer uses a reflection based scheme that pretty completely separates the xml structure from the property setting. I like the reflection-based structure-independent way better, although I think it should only be used with a dtd and xml parser validation-- although this should be done anyway imho. Does anyone else have an opinion? Well, I'm quite partial to the reflection-based technique :-) Me too!! Good work Toby!! It will run into problems with complicated data structures because it pretty much just flattens the XML file into a series of setAttribute calls. I didn't find this problem, I made a pretty complicated data structure load. I used [collections of] inner classes, and the appropriate setXXX method created an inner class instance and had the reflective parser call the setYYY on the inner class. This was for the rule engine adapter I worked on, the rules and other config was all in xml. Still I'll have to look at the Castor stuff. Hmmm, just looked at sun - there's something called JAXB that apparently compiles an xml schema into a custom parser that does 2 way translation between xml and an object tree. Since this is an impending standard it will presumably be the way to go.. for castor as well. david jencks Toby. ___ Jboss-development mailing list [EMAIL PROTECTED] http://lists.sourceforge.net/lists/listinfo/jboss-development ___ Jboss-development mailing list [EMAIL PROTECTED] http://lists.sourceforge.net/lists/listinfo/jboss-development ___ Jboss-development mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/jboss-development
Re: [JBoss-dev] XML config files, whitespace and CDATA... (Castorway = JAXB)
Hmmm, just looked at sun - there's something called JAXB that apparently compiles an xml schema into a custom parser that does 2 way translation between xml and an object tree. Since this is an impending standard it will presumably be the way to go.. for castor as well. I don't really like the idea of having to regenerate classes whenever the DTD/schema changes, but JAXB does look kind of cool. If you look into the expert group for JAXP (JSR 031) you'll find Intalio there. This is the company that's behind Castor and the entire exolab.org. Castor has 2 ways of providing you with marshalling/unmarshalling your Java objects into/from XML SourceGenerator: You just write an XML schema for you XML, run Castor's SourceGenerator, it builds a hierarchy of classes. Objects of these classes are used upon unmarshalling of an XML to build an object tree. You can specify a common superclass for all the generated classes, and package name. more advanced choice XML mapping You have your custom hierarchy of classes that you use to build object trees that you want eventually to marshal into/unmarshal from XML. You write a mapping.xml file which describes the mapping. Castor uses reflection API to marshal/unmarshal using a combination of your mapping.xml and default rules, if something is missing from your mapping description. In either case, you never have to mess with XML parsing yourself, Castor does the fancy footwork of setting all the fields and building the object tree for you. Here is my experience of using Castor. I've used SourceGenerator to create class hierarchies to marshal/unmarshal application.xml, ejb-jar.xml and jboss.xml I use these to automatically generate/modify deployment descriptors. As far as working, the system works well but I find using the class hierarchy generated by SourceGenerator a bit cumbersome. The reason is, probably due to poor XML design of these config files. Perhaps, I am wrong here. Just my 2 cents: ejb-jar.xml - Information that is logically coupled (ejb description, method permissions for this bean and method transaction settings) are located in different entities. The default generated classes, obvously do not have any idea of the logical coupling. When I need to gather all the information about a bean, I have to traverse the objet tree looking for objects which are related and putting them together with my own 'glue' classes. Ideally I would want logically-related items to be glued together during unmarshalling automatically. I'll probably have to look at custom mapping through XML mapping, when I have a clearer picture of things. For those interested, I can provide my XML Schemas of the standard config files that I've been using to build my class hierarchies. http://www.cs.nyu.edu/~akkerman/schemas.jar (I had to recover jboss.xsd, so it may not be exactly correct, I'll recheck it and might update it) Anatoly. Toby. ___ Jboss-development mailing list [EMAIL PROTECTED] http://lists.sourceforge.net/lists/listinfo/jboss-development ___ Jboss-development mailing list [EMAIL PROTECTED] http://lists.sourceforge.net/lists/listinfo/jboss-development
Re: [JBoss-dev] XML config files, whitespace and CDATA
On Wed, 8 Aug 2001, David Jencks wrote: Hi, I like it. Don't we also need a dtd for jboss.jcml (or is there one I haven't found?)? My experience with adding a dtd indicates whitespace handling may be affected-- maybe we should add the dtd and validation first? At the risk of changing the subject ;-) There seem to be two xml-configuration parsing systems in use. The older stuff like for ejb-jar uses code that partially validates the xml while setting properties, whereas the rar deployer uses a reflection based scheme that pretty completely separates the xml structure from the property setting. I like the reflection-based structure-independent way better, although I think it should only be used with a dtd and xml parser validation-- although this should be done anyway imho. Does anyone else have an opinion? I've been working lately with Castor and its SourceGenerator. My current project has to do with reconfiguring and repackaging (splitting) big EARs into pieces with different configs. SourceGenerator was the quickest way for me to get started, without having to learn anything about parsing XML. They Castor framework also has a mapping framework that allows one to map your custom object hierarchy to XML by just writing a schema. Perhaps, this is a way to go. I was also wondering if someone would rewrite JBoss dtds into XML schemas and maintain them. Schemas are much more expressive. I did hack a translation from jboss dtd to schema, there are tools to do that as well, but it would, probably be good if JBoss community had official XML Schemas for its config XMLs. david jencks On 2001.08.08 22:31:13 -0400 Jason Dillon wrote: I mentioned a while ago something about trimming all whitespace from metadata values, but that was rejected because some data might need that whitespace. I also added support to auto trim attribute values from jboss.jcml. Now I would like to suggest changing things such that all leading and trailing whitespace is truncated for all attribtes (jcml and metadata) unless the data is enclosed in a CDATA element. Initially I was not sure if this was possible, but I just check and we can detect if a node is a CDATA via the Node.getNodeType() == Node.CDATA_SECTION_NODE. Lets assume that there is no autoTrim in ConfigurationService and we have a mbean that looks like this: mbean code=org.jboss.web.WebService name=DefaultDomain:service=Webserver attribute name=Port 8083 /attribute /mbean The value of Port should resolve to 8083. mbean code=org.jboss.web.WebService name=DefaultDomain:service=Webserver attribute name=Port !CDATA[8083]] /attribute /mbean The value of Port should still resolve to 8083, since we can cast aside the first node, since it is empty and its sibling is a cdata. To make this work, some modifications will be required to look for empty nodes with siblings that are CDATA. We could also support comments inside, such that this would also work: mbean code=org.jboss.web.WebService name=DefaultDomain:service=Webserver attribute name=Port !-- use this port -- 8083 /attribute /mbean Any ways, I think that this would be very, very helpful to allow more freedom with respect to usage of XML syntax, and provide a mechanism to indicate that whitespace should not be trimmed. Any comments? --jason ___ Jboss-development mailing list [EMAIL PROTECTED] http://lists.sourceforge.net/lists/listinfo/jboss-development ___ Jboss-development mailing list [EMAIL PROTECTED] http://lists.sourceforge.net/lists/listinfo/jboss-development ___ Jboss-development mailing list [EMAIL PROTECTED] http://lists.sourceforge.net/lists/listinfo/jboss-development
Re: [JBoss-dev] XML config files, whitespace and CDATA... and JAXB
On 2001.08.09 17:30:51 -0400 Toby Allsopp wrote: On Wed, Aug 08, 2001 at 11:30:39PM -0400, David Jencks wrote: At the risk of changing the subject ;-) There seem to be two xml-configuration parsing systems in use. The older stuff like for ejb-jar uses code that partially validates the xml while setting properties, whereas the rar deployer uses a reflection based scheme that pretty completely separates the xml structure from the property setting. I like the reflection-based structure-independent way better, although I think it should only be used with a dtd and xml parser validation-- although this should be done anyway imho. Does anyone else have an opinion? Well, I'm quite partial to the reflection-based technique :-) Me too!! Good work Toby!! It will run into problems with complicated data structures because it pretty much just flattens the XML file into a series of setAttribute calls. I didn't find this problem, I made a pretty complicated data structure load. I used [collections of] inner classes, and the appropriate setXXX method created an inner class instance and had the reflective parser call the setYYY on the inner class. This was for the rule engine adapter I worked on, the rules and other config was all in xml. Still I'll have to look at the Castor stuff. Hmmm, just looked at sun - there's something called JAXB that apparently compiles an xml schema into a custom parser that does 2 way translation between xml and an object tree. Since this is an impending standard it will presumably be the way to go.. for castor as well. david jencks Toby. ___ Jboss-development mailing list [EMAIL PROTECTED] http://lists.sourceforge.net/lists/listinfo/jboss-development ___ Jboss-development mailing list [EMAIL PROTECTED] http://lists.sourceforge.net/lists/listinfo/jboss-development
Re: [JBoss-dev] XML config files, whitespace and CDATA
Hi, I like it. Don't we also need a dtd for jboss.jcml (or is there one I haven't found?)? My experience with adding a dtd indicates whitespace handling may be affected-- maybe we should add the dtd and validation first? At the risk of changing the subject ;-) There seem to be two xml-configuration parsing systems in use. The older stuff like for ejb-jar uses code that partially validates the xml while setting properties, whereas the rar deployer uses a reflection based scheme that pretty completely separates the xml structure from the property setting. I like the reflection-based structure-independent way better, although I think it should only be used with a dtd and xml parser validation-- although this should be done anyway imho. Does anyone else have an opinion? david jencks On 2001.08.08 22:31:13 -0400 Jason Dillon wrote: I mentioned a while ago something about trimming all whitespace from metadata values, but that was rejected because some data might need that whitespace. I also added support to auto trim attribute values from jboss.jcml. Now I would like to suggest changing things such that all leading and trailing whitespace is truncated for all attribtes (jcml and metadata) unless the data is enclosed in a CDATA element. Initially I was not sure if this was possible, but I just check and we can detect if a node is a CDATA via the Node.getNodeType() == Node.CDATA_SECTION_NODE. Lets assume that there is no autoTrim in ConfigurationService and we have a mbean that looks like this: mbean code=org.jboss.web.WebService name=DefaultDomain:service=Webserver attribute name=Port 8083 /attribute /mbean The value of Port should resolve to 8083. mbean code=org.jboss.web.WebService name=DefaultDomain:service=Webserver attribute name=Port !CDATA[8083]] /attribute /mbean The value of Port should still resolve to 8083, since we can cast aside the first node, since it is empty and its sibling is a cdata. To make this work, some modifications will be required to look for empty nodes with siblings that are CDATA. We could also support comments inside, such that this would also work: mbean code=org.jboss.web.WebService name=DefaultDomain:service=Webserver attribute name=Port !-- use this port -- 8083 /attribute /mbean Any ways, I think that this would be very, very helpful to allow more freedom with respect to usage of XML syntax, and provide a mechanism to indicate that whitespace should not be trimmed. Any comments? --jason ___ Jboss-development mailing list [EMAIL PROTECTED] http://lists.sourceforge.net/lists/listinfo/jboss-development ___ Jboss-development mailing list [EMAIL PROTECTED] http://lists.sourceforge.net/lists/listinfo/jboss-development
