* @param project project reference.
     * @param artifactType artifact type.
     * @param artifactFile artifact file.
     */
    void attachArtifact(MavenProject project, String artifactType, File artifactFile);

    /**
     * Add or replace an artifact to the current project.
     * @param project the project reference.
     * @param artifactType the type (e.g. jar) or null.

		t.Fatal(err)
	}
	isClosed := rlk.IsClosed()
	if isClosed {
		t.Fatal("File ref count shouldn't be zero")
	}

	// Increase reference count to 2.
	rlk.IncLockRef()

	isClosed = rlk.IsClosed()
	if isClosed {
		t.Fatal("File ref count shouldn't be zero")
	}

	// Decrease reference count by 1.
	if err = rlk.Close(); err != nil {
		t.Fatal(err)
	}

	isClosed = rlk.IsClosed()
	if isClosed {

  public static <T> T verifyNotNull(@Nullable T reference) {
    return verifyNotNull(reference, "expected a non-null reference");
  }

  /**
   * Ensures that {@code reference} is non-null, throwing a {@code VerifyException} with a custom
   * message otherwise.
   *
   * @param errorMessageTemplate a template for the exception message should the check fail. The

        map.put(keyOne, valueOne);
        InternalEntry<Object, Object, ?> entry = segment.getEntry(keyOne, hashOne);

        @SuppressWarnings("unchecked")
        Reference<Object> reference = (Reference<Object>) entry;
        reference.enqueue();

        map.put(keyTwo, valueTwo);
        assertFalse(map.containsKey(keyOne));
        assertFalse(map.containsValue(valueOne));

        map.put(keyOne, valueOne);
        InternalEntry<Object, Object, ?> entry = segment.getEntry(keyOne, hashOne);

        @SuppressWarnings("unchecked")
        Reference<Object> reference = (Reference<Object>) entry;
        reference.enqueue();

        map.put(keyTwo, valueTwo);
        assertFalse(map.containsKey(keyOne));
        assertFalse(map.containsValue(valueOne));

~~ KIND, either express or implied.  See the License for the
~~ specific language governing permissions and limitations
~~ under the License.

 -----
 Maven CLI Options Reference
 -----
 Hervé Boutemy
 -----
 2012-04-29
 -----

Maven CLI Options Reference

        }

        /**
         * Increments the reference count for this statistics object.
         *
         * @return the new reference count after incrementing
         */
        public int increment() {
            return count.incrementAndGet();
        }

        /**
         * Decrements the reference count for this statistics object.
         *

~~ KIND, either express or implied.  See the License for the
~~ specific language governing permissions and limitations
~~ under the License.

 ---
 Maven Core Extensions Reference
 ---
 Hervé Boutemy
 ---
 2016-06-25
 ---

Maven Core Extensions Reference

  Maven core provides default {{{./extension.html}extensions}} as defined in <<</META-INF/maven/extension.xml>>>:

func (set TargetIDSet) Union(sset TargetIDSet) TargetIDSet {
	nset := set.Clone()

	for k := range sset {
		nset.add(k)
	}

	return nset
}

// Difference - returns difference with given set as new set.
func (set TargetIDSet) Difference(sset TargetIDSet) TargetIDSet {
	nset := NewTargetIDSet()
	for k := range set {
		if _, ok := sset[k]; !ok {
			nset.add(k)
		}
	}

	return nset
}

    @Override
    public void setSession(MavenSession session) {
        AtomicReference<MavenSession> reference = DefaultLegacySupport.SESSION.get();
        if (reference != null) {
            reference.set(null);
        }

        if (session == null && reference != null) {
            DefaultLegacySupport.SESSION.remove();
        } else {