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

import java.io.Serial;

import org.apache.maven.api.annotations.Experimental;

@Experimental
public class DependencyResolverException extends MavenException {

    @Serial

 * 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;

import org.apache.maven.building.Source;

/**
 * Provides access to the contents of settings independently of the backing store (e.g. file system, database, memory).
 *
 *
 * @deprecated instead use {@link Source}

    "module": "${pom.artifactId}",
    "version": "${pom.version}",
    "attributes": {
      "org.gradle.status": "${module.status}"
    }
  },
  "createdBy": {
    "maven": {
      "version": "${maven.version}",
      "buildId": "${maven.build.version}"
    }
  },
  "variants": [
    {
      "name": "${variant.jvmEnvironmentVariantName}ApiElements",
      "attributes": {
        "org.gradle.category": "library",

In this case, you could want to document how that external API *should* look like. What *path operation* it should have, what body it should expect, what response it should return, etc.

## An app with callbacks

Let's see all this with an example.

Imagine you develop an app that allows creating invoices.

These invoices will have an `id`, `title` (optional), `customer`, and `total`.

To see all the options you have, checkout <a href="https://docs.pydantic.dev/latest/concepts/types/" class="external-link" target="_blank">Pydantic's Type Overview</a>. You will see some examples in the next chapter.

For example, as in the `Image` model we have a `url` field, we can declare it to be an instance of Pydantic's `HttpUrl` instead of a `str`:

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

import java.io.Serial;

import org.apache.maven.api.annotations.Experimental;

/**
 * An artifact could not correctly being deployed.
 *
 * @since 4.0.0
 */
@Experimental

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

import java.io.Serial;

import org.apache.maven.api.annotations.Experimental;

/**
 * The Exception class thrown by {@link VersionParser}.
 *
 * @since 4.0.0
 */
@Experimental

 * specific language governing permissions and limitations
 * under the License.
 */
package org.apache.maven.model.building;

import java.util.List;

/**
 * Extends the ModelProblemCollector by the capacity of returning the collected problems.
 *
 * @deprecated use {@link org.apache.maven.api.services.ModelBuilder} instead
 */
@Deprecated(since = "4.0.0")

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

import java.io.File;

import org.apache.maven.project.ProjectBuildingException;

/**
 */
public class MavenExecutionException extends Exception {
    private File pomFile;

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

import java.util.Map;

import org.apache.maven.execution.MavenExecutionRequest;
import org.eclipse.aether.repository.AuthenticationSelector;
import org.eclipse.aether.repository.MirrorSelector;