JAXB episode compilation with include does not work

Question

I have 2 schemas A, B. I'm reusing some A elements in B.

I do not use namespaces.

I'm using

<groupId>org.jvnet.jaxb2.maven2</groupId>
<artifactId>maven-jaxb2-plugin</artifactId>
<version>0.9.0</version>

I have have defined an inclusion of schema A in schema B as:

<xs:include schemaLocation="classpath:my.schema.A.xsd"/>

and the catalog as

REWRITE_SYSTEM "classpath:my.schema.A.xsd" "maven:my.schema:schema-a!/A.xsd"

The jaxb configuration goes:

<configuration>
    <generatePackage>my.schema.b</generatePackage>
    <schemaIncludes>
        <includes>B.xsd</includes>
    </schemaIncludes>
    <episodes>
        <episode>
            <groupId>my.schema</groupId>
            <artifactId>schema-a</artifactId>
        </episode>
    </episodes>
    <catalog>src/main/catalog/catalog.cat</catalog>
</configuration>

The issue is that whenever I specify the episode dependency the schema does not generate any classes even though it contains some B elements I want to generate the classes for.

[INFO] Parsing input schema(s)...
[INFO] Compiling input schema(s)...
[INFO] Cleaning package directories.
[INFO] Finished execution.

When I remove the episode it works well and generates classes for schema A as well - which I indeed want to avoid.

Do you have any suggestions?

A sample was published in Jaxb episodic compilation

Answer 1

Ok, I've checked your example. The problem is that you don't use namespaces.

Check your META-INF/sub-jaxb.episode file:

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<jaxb:bindings version="2.1" xmlns:jaxb="http://java.sun.com/xml/ns/jaxb">
  <jaxb:bindings scd="x-schema::">
    <jaxb:schemaBindings map="false">
      <jaxb:package name="schema.episode.a"/>
    </jaxb:schemaBindings>
    <jaxb:bindings scd="person">
      <jaxb:class ref="schema.episode.a.Person"/>
    </jaxb:bindings>
  </jaxb:bindings>
</jaxb:bindings>

You see this <jaxb:bindings scd="x-schema::"> and then <jaxb:schemaBindings map="false">. This basically tells XJC "don't map anything in the empty namespace". Since your second schema (b.xsd) also does not use namespaces, when you use a.xsd's episode file (binding above), you suppress generation of code for b.xsd as well.

To sum it up, when using episodes/separate schema compilation you can't put schemas with one namespace into different episodes. This is exactly the issue with include.

This is not a bug in the maven-jaxb2-plugin. I would not also call it a bug in XJC. It's just how episodes work by default.

See my pull request here, it demonstrates episodic compilation, when namespaces are handled accordingly.