NJ isn't known for trout, and being the most densely populated state in the union, habitat is pretty limited. But where streams exist, they can be as lovely as any trout streams anywhere. And, they can provide isolation and quiet, since most NJ anglers pass them by as they head to the Catskills or the Poconos.
According to the NJ Department of Fish and Wildlife ("NJDFW"), 175 streams in New Jersey support actively reproducing populations of wild trout, and are classified as "Trout Production" or "TP" streams. Of these streams, 36 are regulated as "Wild Trout Streams" or "WTS"
The Wild Trout Streams program in NJ started in 1990, with 36 streams. At least one stream was dropped from the program, and another was added in 2007, a section of the Wanaque River below the Reservoir. According to the NJDFW, selection is "loosely based upon a stream’s ability to support a quality fishery for wild trout and geographic distribution since increasing public awareness and recognition of these waters was considered important". In other words it includes some of the best streams in the state, plus some others included for PR reasons. Moreover, some of the streams no longer support robust populations due to habitat degradation from global climate change and suburban sprawl, while some are still doing quite well. You'll just need to check them out.