This interface is designed to provide a common protocol for objects that generate sequences of pseudorandom values and can easily not only jump but also leap forward, by a large amount (ex. 2¹²⁸), to a very distant point in the state cycle. Typically one will construct a series of RandomGenerator.LeapableGenerator objects by iterative leaping from a single original RandomGenerator.LeapableGenerator object, and then for each such object produce a subseries of objects by iterative jumping. There is little conceptual difference between leaping and jumping, but typically a leap will be a very long jump in the state cycle (perhaps distance 2¹²⁸ or so).

Ideally, all RandomGenerator.LeapableGenerator objects produced by iterative leaping and jumping from a single original RandomGenerator.LeapableGenerator object are statistically independent of one another and individually uniform. In practice, one must settle for some approximation to independence and uniformity. In particular, a specific implementation may assume that each generator in a stream produced by the leaps method is used to produce (by jumping) a number of objects no larger than 2⁶⁴. Implementors are advised to use algorithms whose period is at least 2¹⁹¹.

Methods are provided to perform a single leap operation and also to produce a stream of generators produced from the original by iterative copying and leaping of internal state. The generators produced must implement the RandomGenerator.JumpableGenerator interface but need not also implement the RandomGenerator.LeapableGenerator interface. A typical strategy for a multithreaded application is to create a single RandomGenerator.LeapableGenerator object, calls its leaps method exactly once, and then parcel out generators from the resulting stream, one to each thread. Then the jump() method of each such generator be called to produce a substream of generator objects.

Objects that implement RandomGenerator.LeapableGenerator are typically not cryptographically secure. Consider instead using SecureRandom to get a cryptographically secure pseudo-random number generator for use by security-sensitive applications.