}
        return obj;
    }

    protected static <T> Collection<T> unmodifiable(Collection<T> obj) {
        return obj != null && !obj.isEmpty()
                ? Collections.unmodifiableCollection(new ArrayList<>(obj))
                : Collections.emptyList();
    }

        exceptions.iterator().next());
    ArrayList<? extends Throwable> temp = new ArrayList<>(exceptions);
    this.exceptions = Collections.unmodifiableCollection(temp);
  }

  /** See {@link #create(Collection)}. */
  static RuntimeException create(Throwable... exceptions) {
    ArrayList<Throwable> temp = new ArrayList<>(Arrays.asList(exceptions));

        return Collections.unmodifiableCollection(attached);
    }

    @Override
    public Collection<ProducedArtifact> getAllArtifacts(Project project) {
        ArrayList<ProducedArtifact> result = new ArrayList<>(2);
        result.addAll(project.getArtifacts());
        result.addAll(getAttachedArtifacts(project));
        return Collections.unmodifiableCollection(result);
    }

    @Override

 * object being tested, but the reverse could not be true. This behavior is consistent with the
 * JDK's collection wrappers, such as {@link java.util.Collections#unmodifiableCollection}. Use an
 * interface-specific subclass of {@code ForwardingObject}, such as {@link ForwardingList}, to
 * preserve equality behavior, or override {@code equals} directly.
 *