N.J. Stat. § 18A:66-15
In computing for retirement or for purposes of resignation or separation from service under sections 18A:66-36 and 18A:66-37 the total service of a member about to be retired, the retirement system shall credit him with all service rendered by him since he last became a member and in addition, with all the service to which he is entitled and with no other service. Except as otherwise provided in this article, such service credit shall be final and conclusive for retirement purposes, or for purposes of resignation under sections 18A:66-36 and 18A:66-37, unless the member shall discontinue his service for more than two consecutive years. In the case of a member for whom compensation is defined in paragraph (2) of subsection d. of N.J.S. 18A:66-2, the retirement system shall credit the member with the time of all service rendered by the member during the part of any year that the member was a participant of the Defined Contribution Retirement Program, pursuant to paragraph (5) of subsection a. of section 2 of P.L. 2007, c. 92(C.43:15C-2) as amended by section 12 of P.L. 2007, c. 103, and making contributions to that program.
For the purpose of computing service for retirement purposes, the board of trustees shall fix and determine by appropriate rules and regulations how much service in any year shall equal a year of service and part of a year of service. Not more than one year shall be credited for all service in a calendar year.
N.J.S. § 18A:66-15