How to add specific configuration to a Maven plugin

Question

In my pom.xml I configure a plugin to convert certain Protobuf files to Java class files. It looks like this:

<plugin>
        <groupId>com.github.igor-petruk.protobuf</groupId>
        <artifactId>protobuf-maven-plugin</artifactId>
        <version>0.5.3-SNAPSHOT</version>
        <executions>
                 <execution>
                         <goals>
                                 <goal>run</goal>
                         </goals>
                 </execution>
        </executions>
        <configuration>
              <protocCommand>${basedir}/protoc/bin/protoc</protocCommand>
              <inputDirectories>
                    <inputDirectory>proto</inputDirectory>
              </inputDirectories>
        </configuration>
</plugin>

Out of this Maven generates the .classpath file with the following entry:

<classpathentry kind="src" output="target/classes" path="target/generated-sources/protobuf">
    <attributes>
        <attribute name="optional" value="true"/>
        <attribute name="maven.pomderived" value="true"/>
    </attributes>
</classpathentry>

What I would now like Maven to do is to add an additional "attribute" entry to that classpath entry so that the entry looks like this:

<classpathentry kind="src" output="target/classes" path="target/generated-sources/protobuf">
    <attributes>
        <attribute name="optional" value="true"/>
        <attribute name="maven.pomderived" value="true"/>
        <attribute name="ignore_optional_problems" value="true"/>
    </attributes>
</classpathentry>

Like that I won't get warnings from that part of the code.

At the moment I just don't know how to do that. Which files or other settings do I have to edit? Where in Eclipse can I do that?
But this is more or less a general question as to how Maven can be modified to include customized entries, because we have some more spots where we would want to add custom things in.

Answer 1

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