Need file from src/main/resources in generate-sources phase for annotation processor config

Question

I have an annotation processor that I need to give some configuration to tell it a few details about how I want it to generate source code. I spent a good deal of time trying to understand why the file was sitting in target/classes after the build, but I was getting an exception during annotation processing stating that the file did not, in fact, exist.

After much digging I finally figured out why the file (stored in src/main/resources/config) isn't getting copied over to target/classes/config for my annotation processor to read - generate-sources happens before process-resources in the build lifecycle, so the file isn't getting copied over in time for the annotation processor to see it during its run. (maven build lifecycle reference: http://maven.apache.org/ref/3.2.2/maven-core/lifecycles.html)

Here's a high level overview of what I'm trying to do:

I have a jar that I've built that processes annotations and generates interface classes from the information in the annotations to base a client api off of. The idea is that including that jar as a compile-time dependency should automatically generate this code for any project that uses these annotations (with as little-as-possible additional configuration in the client project's pom.xml).

How do I go about either:

1. Getting (at a minimum) the config.xml portion of process-resources to happen before generate-sources
2. Adding the file to the classpath of the annotation processor in some other way (we don't need this file in the output archive, so this might be better)
3. I am also open to other (clean) ways of getting configuration information into the annotation processor if there is a better way that I haven't thought of

I would prefer not to write a whole maven plugin for this if possible.

Edit: Here are the relevant parts of the <build> portion of my client pom per request:

<build>
    <finalName>OurApp</finalName>
    <resources>
        <resource>
            <!-- My config.xml file is located here -->
            <directory>src/main/resources</directory>
        </resource>
        <resource>
            <directory>src/main/webapp</directory>
            <includes>
                <include>*.*</include>
            </includes>
            <excludes><exclude>${project.build.directory}/generated-sources/**</exclude></excludes>
        </resource>
    </resources>
    <plugins>
        <!-- Omit Annotation Processor lib from the compilation phase because the code generated is destined for another, separate jar -->
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-compiler-plugin</artifactId>
            <version>${maven-compiler-plugin.version}</version>
            <executions>
              <execution>
                <id>annotation-processing</id>
                <phase>generate-sources</phase>
                <goals>
                  <goal>compile</goal>
                </goals>
                <configuration>
                  <proc>only</proc>
                </configuration>
              </execution>
              <!-- Compile the rest of the code in the normal compile phase -->
              <execution>
                <id>compile-without-generated-source</id>
                <phase>compile</phase>
                <goals>
                  <goal>compile</goal>
                </goals>
                <configuration>
                  <excludes><exclude>${project.build.directory}/generated-sources/**</exclude></excludes>
                  <proc>none</proc>
                  <!-- http://jira.codehaus.org/browse/MCOMPILER-230 because this doesn't
                       work in the opposite direction (setting failOnError in the other execution 
                       and leaving the default top-level value alone) -->
                  <failOnError>true</failOnError>
                </configuration>
              </execution>
            </executions>
            <configuration>
                <source>${java.version}</source>
                <target>${java.version}</target>
                <proc>only</proc>
                <failOnError>false</failOnError>
            </configuration>
        </plugin>
        <!-- package generated client into its own SOURCE jar -->
        <plugin>
            <artifactId>maven-assembly-plugin</artifactId>
            <version>2.4.1</version>
            <configuration>
                <descriptorRefs>
                    <descriptorRef>generated-client-source</descriptorRef>
                </descriptorRefs>
            </configuration>
            <dependencies>
                <dependency>
                    <groupId>com.package</groupId>
                    <artifactId>our-api</artifactId>
                    <version>${our-api.version}</version>
                </dependency>
            </dependencies>
            <executions>
                <execution>
                    <id>client-source</id>
                    <phase>package</phase>
                    <goals>
                        <goal>single</goal>
                    </goals>
                </execution>
            </executions>
        </plugin>
    </plugins>
</build>

Answer 1

So since this file is only needed at compile time, and since any attempt to draw it directly from the classpath was failing miserably, I decided to plop it in the project root, and add a compiler argument in Maven to point to the file.

  <compilerArgs>
      <compilerArg>-AconfigFilePath=${project.basedir}/config.xml</compilerArg>
  </compilerArgs>

Not quite as elegant as getting it off the classpath automatically, but still better than supplying all the configuration elements as separate properties.

Thanks for the suggestions