import org.apache.maven.api.model.DependencyManagement;
import org.apache.maven.api.model.Exclusion;
import org.apache.maven.api.model.Model;
import org.apache.maven.model.building.ModelBuildingRequest;
import org.apache.maven.model.building.ModelProblemCollector;
import org.apache.maven.model.merge.MavenModelMerger;

/**
 * Handles injection of dependency management into the model.
 *

              <include>org.apache.maven.toolchain.building</include>
              <include>org.apache.maven.toolchain.io</include>
              <include>org.apache.maven.toolchain.io.xpp3</include>
              <include>org.apache.maven.toolchain.merge</include>
            </includes>
            <excludes>

import org.apache.maven.model.Model;
import org.apache.maven.model.Plugin;
import org.apache.maven.model.PluginExecution;
import org.apache.maven.model.PluginManagement;
import org.apache.maven.model.building.ModelBuildingRequest;
import org.apache.maven.model.building.ModelProblemCollector;

/**
 * Handles expansion of general build plugin configuration into individual executions.
 *

import org.apache.maven.internal.impl.DefaultSession;
import org.apache.maven.internal.impl.InternalMavenSession;
import org.apache.maven.internal.impl.InternalSession;
import org.apache.maven.model.building.ModelBuildingException;
import org.apache.maven.model.building.ModelProblem;
import org.apache.maven.repository.RepositorySystem;
import org.apache.maven.repository.internal.MavenRepositorySystemUtils;
import org.apache.maven.session.scope.internal.SessionScope;

So, it was a complete additional system.

It is not very popular or used nowadays.

## OpenAPI

OpenAPI (previously known as Swagger) is the open specification for building APIs (now part of the Linux Foundation).

**FastAPI** is based on **OpenAPI**.

That's what makes it possible to have multiple automatic interactive documentation interfaces, code generation, etc.

import org.apache.maven.execution.MavenSession;
import org.apache.maven.model.Repository;
import org.apache.maven.model.building.ModelBuildingException;
import org.apache.maven.model.building.ModelBuildingRequest;
import org.apache.maven.model.building.ModelSource;
import org.apache.maven.model.building.UrlModelSource;
import org.apache.maven.plugin.LegacySupport;
import org.apache.maven.profiles.ProfileManager;

 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
package org.apache.maven.building;

/**
 * Describes a problem that was encountered during settings building. A problem can either be an exception that was
 * thrown or a simple string message. In addition, a problem carries a hint about its source, e.g. the settings file
 * that exhibits the problem.

 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
package org.apache.maven.model.building;

import java.util.Objects;

import org.apache.maven.building.Source;
import org.apache.maven.model.Model;

/**
 * Holds a model along with some auxiliary information. This internal utility class assists the model builder during POM

 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
package org.apache.maven.settings.building;

/**
 * Describes a problem that was encountered during settings building. A problem can either be an exception that was
 * thrown or a simple string message. In addition, a problem carries a hint about its source, e.g. the settings file
 * that exhibits the problem.

    }

    private gradlebuild.docs.dsl.docbook.model.ClassDoc loadClassDoc(String className) {
        if (currentlyBuilding.contains(className)) {
            throw new RuntimeException("Cycle building $className. Currently building $currentlyBuilding")
        }
        currentlyBuilding.addLast(className)
        try {
            ClassMetaData classMetaData = classMetaData.find(className)
            if (!classMetaData) {