*/

This document outlines the concerns of a general plugin manager that would be used in conjunction with any Plexus-based application. The following outlined concerns are an attempt to describe what a plugin manager would need to do for Maven and for Nexus.

h2. Concerns for the plugin manager

h3. Resolving the dependencies of a plugin

      <role>org.apache.maven.wagon.Wagon</role>
      <role-hint>a</role-hint>
      <implementation>org.apache.maven.artifact.manager.WagonA</implementation>
    </component>
    <component>
      <role>org.apache.maven.wagon.Wagon</role>
      <role-hint>b1</role-hint>
      <implementation>org.apache.maven.artifact.manager.WagonB</implementation>
    </component>
    <component>
      <role>org.apache.maven.wagon.Wagon</role>

    private final ConcurrentHashMap<String, Type> usedTypes;

    private final LegacyArtifactHandlerManager manager;

    @Inject
    public DefaultTypeRegistry(
            List<TypeProvider> providers, LanguageRegistry languageRegistry, LegacyArtifactHandlerManager manager) {
        this.types = nonNull(providers, "providers").stream()
                .flatMap(p -> p.provides().stream())

### Async Context Manager

If you check, the function is decorated with an `@asynccontextmanager`.

That converts the function into something called an "**async context manager**".

{* ../../docs_src/events/tutorial003.py hl[1,13] *}

A **context manager** in Python is something that you can use in a `with` statement, for example, `open()` can be used as a context manager:

```Python
with open("file.txt") as file:

.29.2](https://console.cloud.google.com/gcr/images/k8s-artifacts-prod/us/kube-controller-manager) | [amd64](https://console.cloud.google.com/gcr/images/k8s-artifacts-prod/us/kube-controller-manager-amd64), [arm64](https://console.cloud.google.com/gcr/images/k8s-artifacts-prod/us/kube-controller-manager-arm64), [ppc64le](https://console.cloud.google.com/gcr/images/k8s-artifacts-prod/us/kube-controller-manager-ppc64le), [s390x](https://console.cloud.google.com/gcr/images/k8s-artifacts-prod/us/kube...

.28.7](https://console.cloud.google.com/gcr/images/k8s-artifacts-prod/us/kube-controller-manager) | [amd64](https://console.cloud.google.com/gcr/images/k8s-artifacts-prod/us/kube-controller-manager-amd64), [arm64](https://console.cloud.google.com/gcr/images/k8s-artifacts-prod/us/kube-controller-manager-arm64), [ppc64le](https://console.cloud.google.com/gcr/images/k8s-artifacts-prod/us/kube-controller-manager-ppc64le), [s390x](https://console.cloud.google.com/gcr/images/k8s-artifacts-prod/us/kube...

pha.2](https://console.cloud.google.com/gcr/images/k8s-artifacts-prod/us/kube-controller-manager) | [amd64](https://console.cloud.google.com/gcr/images/k8s-artifacts-prod/us/kube-controller-manager-amd64), [arm64](https://console.cloud.google.com/gcr/images/k8s-artifacts-prod/us/kube-controller-manager-arm64), [ppc64le](https://console.cloud.google.com/gcr/images/k8s-artifacts-prod/us/kube-controller-manager-ppc64le), [s390x](https://console.cloud.google.com/gcr/images/k8s-artifacts-prod/us/kube...

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

import java.util.List;

import org.apache.maven.artifact.Artifact;
import org.apache.maven.artifact.repository.ArtifactRepository;
import org.apache.maven.wagon.ResourceDoesNotExistException;

import static org.eclipse.aether.impl.scope.BuildScopeQuery.singleton;
import static org.eclipse.aether.impl.scope.BuildScopeQuery.union;

/**
 * Maven4 scope configurations. Configures scope manager to support Maven4 scopes.
 * <p>
 * This manager supports all the new Maven 4 dependency scopes defined in {@link DependencyScope}.
 *
 * @since 2.0.0
 * @deprecated since 4.0.0, use {@code maven-api-impl} jar instead
 */

import org.eclipse.aether.internal.impl.scope.ScopeManagerImpl;
import org.eclipse.aether.resolution.ArtifactDescriptorPolicy;
import org.eclipse.aether.util.artifact.DefaultArtifactTypeRegistry;
import org.eclipse.aether.util.graph.manager.ClassicDependencyManager;
import org.eclipse.aether.util.graph.selector.AndDependencySelector;
import org.eclipse.aether.util.graph.selector.ExclusionDependencySelector;