Maven Report Configuration vs Build Configuration

Question

It is interesting what is the differences between

report->configuration element and build->configuration element in POM.

It is written in POM references:

Subtle difference is that a plugin configuration under the reporting element works as build plugin configuration, although the opposite is not true (a build plugin configuration does not affect a reporting plugin).

See http://maven.apache.org/pom.html#Reporting

Could you give particular example of the differences in behaviour?

Answer 1

This statement means the following:

If we have report generation plugin configuration like

  <build>
      <plugins>
          <plugin>
              <groupId>org.apache.maven.plugins</groupId>
              <artifactId>maven-project-info-reports-plugin</artifactId>
              <version>2.8</version>

              <configuration>
                  <linkOnly>true</linkOnly>
              </configuration>
          </plugin>
      </plugins>
  </build>

then linkOnly configuration property won't be used when invoking site generation command

mvn site

Instead, we should use the same configuration under reporting element:

  <reporting>
      <plugins>
          <plugin>
              <groupId>org.apache.maven.plugins</groupId>
              <artifactId>maven-project-info-reports-plugin</artifactId>
              <version>2.8</version>

              <configuration>
                  <linkOnly>true</linkOnly>
              </configuration>

              <reportSets>
                  <reportSet>
                      <reports>
                          <report>license</report>
                      </reports>
                  </reportSet>
              </reportSets>
          </plugin>
      </plugins>
  </reporting>

Here we generate only license report with configuration parameter linkOnly=true.

I.e. build configuration is not used.

Note: If we explicitly invoke report generation goal "license"

mvn project-info-report:license

then it will use configuration under build element. I.e. we have opposite behaviour here.