All hearings under this chapter shall be heard by the court without a jury. Unless the parties and the court agree otherwise, proceedings of contested hearings shall be recorded. The general public shall be excluded and only those persons shall be admitted whose presence is requested by any person entitled to notice under this chapter or whom the judge finds to have a direct interest in the case or in the work of the court. Persons so admitted shall not disclose any information obtained at the hearing which would identify the individual adoptee or parent involved. The court may require the presence of witnesses deemed necessary to the disposition of the petition, including persons making any report, study, or examination which is before the court if those persons are reasonably available. A person who has executed a valid waiver need not appear at the hearing. If the court finds that it is in the child's best interest, the child may be excluded from the hearing.