March 2007
Intermediate to advanced
54 pages
1h 25m
English
Content preview from Checking Java ProgramsBecome an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.
Dynamic Checking with NASA's Java PathFinder
It's not the Mars PathFinder (http://mpfwww.jpl.nasa.gov/default.html), but the Java PathFinder (http://javapathfinder.sourceforge.net) has been to space. Quoting the web site, Java PathFinder was developed "at the NASA Ames Research Center. Started in 1999 as a feasibility study for software model checking, JPF has found its way into academia and industry, and has even helped detect defects in real spacecraft."
NASA's Java PathFinder (JPF for short) is an instrumented JVM that provides a state model checker. It runs your program by trying all potential execution paths through it, checking properties as it goes to detect problems like deadlocks or unhandled exceptions. JPF is good at finding those rarely occurring, unpredictable and impossible-to-see concurrency defects in multithreaded programs. In trying to execute all potential paths through your program, JPF uses two important optimizations:
Backtracking lets JPF back up from, for example, the end of a method and try different paths, instead of starting the program over from the beginning.
State Matching lets JPF compare previous values of your program's state (which is stored as a heap and thread-stack snapshot) to see if it's already "been there, done that."
Even so, there is the possibility for the number of states that have to be tried, particularly in the presence of threading, to become computationally infeasible. So they use some additional techniques:
Configurable (user-provided) ...
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
and much more.
Read now
Unlock full access
More than 5,000 organizations count on O’Reilly
O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.