Xjc in code - not command line

Question

I'm new to java xml, and may be wanting to force a square peg through a round hole but, I would like to create source files using xjc from dtd's and xjs's from datasources or other basically non file based sources. Am I looking at the wrong tool? I don't want to write the dtd's and xjs's to disk and then compile through a command line.
Thanks
fj

Answer 1

Thanks Danny,
I've read through the pdf's got the example to work as well as many in the java_xml_pack-spring-02-dev. Wipped up a proof of concept database, some JDBC classess, and a servlet. Went through XML Hell with Tomcat 4, then deleted the xerces from the common folder, changed some classpath statements and the example works being triggered from a servlet. Then I gabbed DTD, XJS, and XML content like so
(1) a couple prepared statements
first statement to retrieve an xml file from the database
"SELECT XML_NAM, XML_CNT " +
"FROM XML_CNT_JAXB "
second one to retrieve the DTD and XJS content from a database
"SELECT INFO_DTD_CNT.DTD_CNT, INFO_XJS_CNT.XJS_CNT " +
"FROM INFO_DTDXJS_BLD " +
"INNER JOIN " +
"INFO_DTD_CNT ON INFO_DTDXJS_BLD.DTD_ID = INFO_DTD_CNT.DTD_ID " +
"INNER JOIN " +
"INFO_XJS_CNT ON INFO_DTDXJS_BLD.XJS_ID = INFO_XJS_CNT.XJS_ID " +
"WHERE (INFO_DTDXJS_BLD.DTD_BLD_NM = ?)"
(2) execute and get results
ResultSet resultSet = sqlXML_CNT.executeQuery();
etc..
(3) place resultset XML strings in an InputStream
sbin_XML_CNT = new StringBufferInputStream(str_XML_CNT);
etc..
(4) now it works fine if you already used xjc to create your java classes and compile... then you can just use the BufferedInputStream to build your trees
buildTrees(StringBufferInputStream bIn)
foo = foo.unmarshal(bIn);
etc...
(5) what I don' want to do with the DTD and XJS is stream the content write the file to disk and execute commands to build the java files..
Process myXJC = Runtime.getRuntime().exec("myXJC.bat");
Again I'm new to Java XML, but if people want to use an XML file that does not have a DTD or XJS within a system, say they are requesting a new content area, the app then gives them a screen to define the DTD or builds a DTD for them or whatever, and then asks them for the content they want to manipulate or reports or whatever, and them creates an XJS, Java classes are then built compiled and someone can test and approve them... etc then save them to disk, database, a distributed server,.. etc
I'm sure there is a way to compile Java from within a application. what I'm not sure of is if there is a way avoid the Java -jar %JAXB_HOME%\lib\jaxb-xjc-1.0-ea.jar file.dtd file.xjs -d directory from command line.
If you could point me to any articles or book chapters address this, I'd really appreciate it!
Thanks
fj