Lecture Notes in Computer Science 3472

18 Run-Time Verification 555
Although these are very early days, some of the projects already carried out
in run-time verification produce tools that, when looked at properly, are simply
debuggers with fancy features and/or provide good tracing mechanisms. Examples
include, inter alia, Jass [BFMW01], Opium [Duc90], Morphine [DJ01], Coca
[Duc99], DynaMICs [GRMD01], Daikon [ECGN01], and ESC/Java [RLNS00].
Some approaches in run-time verification include collecting statistics during runtime
to perform some form of debugging later on. However, what is encouraging
amongst the majority of these projects and tools is the use of linear time logic
(or extensions of it) to describe the monitor that monitors the program behavior
[Gei01] or as the basis of a specification language to specify the properties to
monitor [DGJV01]. In particular, Hakansson et al. [HJL03] proposed the generation
of on-line test oracles with a rich logic which contains past operators, metric
time, and can handle data values by means of the quantification construct.
What is needed is a tool (or set of) that software professionals can use to
specify requirements, to design the system, to code, to test, to deploy, and to
monitor the software while running, something like an integrated development
environment (IDE) that combines those attributes. JPAX [HR01a] is going in
the right direction. This is an IDE that tries to combine the positive attributes
of testing, i.e. in terms of scaling up, and that of formal methods, i.e. by providing
temporal formulas for specification. It falls shy to be called a run-time
verification tool as it only monitors a program and emits its results, it does
not automatically correct the monitored program. MaCS [KLS + 02] is going in
the right direction towards being called a run-time verification tool. It combines
monitoring a program with steering that program if, while running, fails to concur
with its specification. There are some obvious problems to tackle in this area,
such as how far forward in a running program should a tool look to correct, and
the computational complexity that is inherent in tackling such a problem.