private final MessageBuilderFactory messageBuilderFactory;

    /**
     * Default ctor is used in IT and most probably some 3rd party code. For those cases, we do provide sane defaults
     * but given this is a component, injection should be used, replacing direct instantiation.
     *
     * @deprecated Do not use this ctor directly, inject this component instead.
     */
    @Deprecated

    /*
     * Don't bother testing. All non-primitive parameters are used only to construct error messages.
     * We never want to pass null for them, so we haven't annotated them to say that null is
     * allowed. But at the same time, it seems wasteful to bother inserting the checkNotNull calls
     * that NullPointerTester wants.
     *
     * (This empty method disables the automatic null testing provided by PackageSanityTests.)
     */

      element = null;
      extras = emptyList();
    }

    IllegalArgumentException multiples(boolean overflow) {
      StringBuilder sb =
          new StringBuilder().append("expected one element but was: <").append(element);
      for (Object o : extras) {
        sb.append(", ").append(o);
      }
      if (overflow) {
        sb.append(", ...");
      }
      sb.append('>');

  @Override
  @J2ktIncompatible // Incompatible return type change. Use inherited implementation
  public Object[] toArray() {
    /*
     * If we could, we'd declare the no-arg `Collection.toArray()` to return "Object[] but elements
     * have the same nullness as E." Since we can't, we declare it to return nullable elements, and
     * we can override it in our non-null-guaranteeing subtypes to present a better signature to
     * their users.

    assertEquals(3, uniqueEntries.size());
  }

  // Wrapper of EnumMultiset factory methods, because we need to skip create(Class).
  // create(Enum1.class) is equal to create(Enum2.class) but testEquals() expects otherwise.
  // For the same reason, we need to skip create(Iterable, Class).
  private static class EnumMultisetFactory {
    @Keep // used reflectively by testEquals

// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Affero General Public License for more details.
//

// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Affero General Public License for more details.
//

// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Affero General Public License for more details.
//

// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Affero General Public License for more details.
//

// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Affero General Public License for more details.
//