  This paper describes the Jas4pp framework for exploring physics cases and for
detector-performance studies of future particle collision experiments. Jas4pp
is a multi-platform Java program for numeric calculations, scientific
visualization in 2D and 3D, storing data in various file formats and displaying
collision events and detector geometries. It also includes complex
data-analysis algorithms for function minimisation, regression analysis, event
reconstruction (such as jet reconstruction), limit settings and other libraries
widely used in particle physics. The framework can be used with several
scripting languages, such as Python/Jython, Groovy and JShell. Several
benchmark tests discussed in the paper illustrate significant improvements in
the performance of the Groovy and JShell scripting languages compared to the
standard Python implementation in C. The improvements for numeric computations
in Java are attributed to recent enhancements in the Java Virtual Machine.
