import java.util.Map;

import org.apache.maven.artifact.handler.manager.ArtifactHandlerManager;
import org.apache.maven.artifact.repository.ArtifactRepository;
import org.apache.maven.artifact.repository.ArtifactRepositoryPolicy;
import org.apache.maven.artifact.repository.MavenArtifactRepository;
import org.apache.maven.artifact.repository.layout.ArtifactRepositoryLayout;
import org.apache.maven.artifact.repository.layout.DefaultRepositoryLayout;

<project>
  <parent>
    <artifactId>p0</artifactId>
    <groupId>maven</groupId>
    <version>1.0</version>
  </parent>
  <modelVersion>4.0.0</modelVersion>
  <groupId>maven</groupId>
  <artifactId>p1</artifactId>
  <packaging>pom</packaging>
  <name>p1</name>
  <version>1.0</version>
  <scm>
    <url>scm-url</url>
  </scm>

<project>
  <parent>
    <artifactId>p2</artifactId>
    <groupId>maven.t01</groupId>
    <version>1.0</version>
  </parent>
  <modelVersion>4.0.0</modelVersion>
  <groupId>maven.t01</groupId>
  <artifactId>p3</artifactId>
  <packaging>pom</packaging>
  <name>p3</name>
  <version>1.0</version>
  <organization>
    <name>p3-org</name>
  </organization>

<project>
  <modelVersion>4.0.0</modelVersion>
  <artifactId>aid</artifactId>
  <groupId>gid</groupId>
  <version>0.1</version>

  <build>
    <plugins>
      <plugin>
        <groupId>test</groupId>
        <artifactId>good</artifactId>
        <version>1.0</version>
      </plugin>
      <plugin>
        <groupId>test</groupId>
        <artifactId>mip</artifactId>
        <version>${missing.property}</version>

<project>
  <modelVersion>4.0.0</modelVersion>
  <groupId>maven-test</groupId>
  <artifactId>t06-b</artifactId>
  <packaging>jar</packaging>
  <version>1.0</version>
  <dependencies>
    <dependency>
      <groupId>maven-test</groupId>
      <artifactId>t06-c</artifactId>
      <version>1.0</version>
      <type>jar</type>
      <scope>compile</scope>
    </dependency>
    <dependency>
      <groupId>maven-test</groupId>

<project>
  <modelVersion>4.0.0</modelVersion>
  <artifactId>foo</artifactId>
  <groupId>foo</groupId>
  <version>99.44</version>
  <packaging>jar</packaging>

  <dependencies>
    <dependency>
      <groupId>gid</groupId>
      <artifactId>aid</artifactId>
      <version>1.0</version>
      <exclusions>
        <exclusion>
          <groupId>test?</groupId>
          <artifactId>*</artifactId>
        </exclusion>
      </exclusions>

        <groupId>maven-test</groupId>
        <artifactId>t06-b</artifactId>
        <version>1.1</version>
      </dependency>
      <dependency>
        <groupId>maven-test</groupId>
        <artifactId>t06-c</artifactId>
        <version>1.0</version>
      </dependency>
      <dependency>
        <groupId>maven-test</groupId>
        <artifactId>t06-d</artifactId>
        <version>1.2</version>
        <scope>test</scope>

import javax.inject.Named;
import javax.inject.Singleton;

import java.util.Map;

import org.apache.maven.artifact.repository.ArtifactRepository;
import org.apache.maven.artifact.resolver.ArtifactNotFoundException;
import org.apache.maven.artifact.resolver.ArtifactResolutionException;
import org.apache.maven.artifact.versioning.InvalidVersionSpecificationException;
import org.apache.maven.execution.MavenSession;

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

import java.util.Collections;
import java.util.List;

import org.apache.maven.artifact.Artifact;
import org.apache.maven.artifact.DefaultArtifact;
import org.apache.maven.artifact.handler.ArtifactHandler;
import org.apache.maven.model.Dependency;
import org.apache.maven.model.Plugin;

/**

  <modelVersion>4.0.0</modelVersion>

  <parent>
    <groupId>cyclic-reference</groupId>
    <artifactId>parent</artifactId>
    <version>1.0-SNAPSHOT</version>
  </parent>
  <artifactId>module-b</artifactId>

  <dependencies>
    <dependency>
      <groupId>cyclic-reference</groupId>
      <artifactId>module-a</artifactId>
      <version>1.0-SNAPSHOT</version>
    </dependency>
  </dependencies>