void testValidate() {
        Artifact plugin = new DefaultArtifact(
                "org.apache.maven.its.plugins",
                "maven-it-plugin",
                "0.1",
                "compile",
                "jar",
                null,
                new DefaultArtifactHandler("ignore"));
        PluginDescriptor descriptor = new PluginDescriptor();
        descriptor.setGroupId("org.apache.maven.its.plugins");

    /**
     * Default URL to download the maven-wrapper.jar from, if no 'downloadUrl' is provided.
     */
    private static final String DEFAULT_DOWNLOAD_URL = "https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/"
        + WRAPPER_VERSION + "/maven-wrapper-" + WRAPPER_VERSION + ".jar";

    /**
     * Path to the maven-wrapper.properties file, which might contain a downloadUrl property to

        if ("JAR".equals(packaging)) {
            plugins = new LinkedHashSet<>();

            plugins.add(newPlugin("maven-compiler-plugin", "compile", "testCompile"));
            plugins.add(newPlugin("maven-resources-plugin", "resources", "testResources"));
            plugins.add(newPlugin("maven-surefire-plugin", "test"));
            plugins.add(newPlugin("maven-jar-plugin", "jar"));

<project>
  <modelVersion>4.0.0</modelVersion>
  <groupId>maven-test</groupId>
  <artifactId>t06-a</artifactId>
  <packaging>jar</packaging>
  <version>1.0</version>
  <repositories>
    <repository>
      <id>central</id>
      <name>Fake Maven Central Repository</name>
      <url>file://dummy</url>
    </repository>
  </repositories>
  <dependencies>
    <dependency>
      <groupId>maven-test</groupId>

<project>
  <modelVersion>4.0.0</modelVersion>
  <groupId>maven-test</groupId>
  <artifactId>t07-a</artifactId>
  <packaging>jar</packaging>
  <version>1.0</version>
  <repositories>
    <repository>
      <id>central</id>
      <name>Fake Maven Central Repository</name>
      <url>file://dummy</url>
    </repository>
  </repositories>
  <dependencies>
    <dependency>
      <groupId>maven-test</groupId>

        }
    }

    /**
     * Traverses classes contained in a Jar file.
     * <p>
     * If the specified Jar file has the extension <code>.war</code>, only entries whose path starts with the prefix <code>WEB-INF/classes</code> are traversed.
     * The handler receives the entry name excluding the prefix. For example, if the Jar file contains <code>/WEB-INF/classes/ccc/ddd/Eee.class</code>,

<project>
  <modelVersion>4.0.0</modelVersion>
  <groupId>maven-test</groupId>
  <artifactId>t05-b</artifactId>
  <packaging>jar</packaging>
  <version>2.0</version>
  <dependencies>
    <dependency>
      <groupId>maven-test</groupId>
      <artifactId>t05-c</artifactId>
      <version>1.0</version>
      <type>jar</type>
      <scope>compile</scope>
    </dependency>
    <dependency>
      <groupId>maven-test</groupId>

<project>
  <modelVersion>4.0.0</modelVersion>
  <groupId>maven-test</groupId>
  <artifactId>t08-b</artifactId>
  <packaging>jar</packaging>
  <version>1.0</version>
  <dependencies>
    <dependency>
      <groupId>maven-test</groupId>
      <artifactId>t08-c</artifactId>
      <version>1.0</version>
      <type>jar</type>
      <scope>compile</scope>
    </dependency>
    <dependency>
      <groupId>maven-test</groupId>

            <phase>post-integration-test</phase>
            <goals><goal>test-jar</goal></goals>
          </execution>
        </executions>
      </plugin>
      <plugin>
        <artifactId>maven-jar-plugin</artifactId>
        <executions>
          <execution>
            <id>create-test-jar</id>
            <goals><goal>test-jar</goal></goals>
          </execution>
        </executions>
      </plugin>

        }
        return protocol;
    }

    /**
     * Returns the {@link File} object of the Jar file indicated by the URL.
     *
     * @param fileUrl
     *            The URL of the Jar file. Must not be {@literal null}.
     * @return The {@link File} of the Jar file.
     */
    public static File toFile(final URL fileUrl) {
        assertArgumentNotNull("fileUrl", fileUrl);