> > >>>> On 12/14/11 5:45 PM, hernan wrote: > >>>>> I'm using Tomcat 7.0 for developing a new application. A key > >>>>> component in the application have to run an external not > >>>>> multithreaded application. > >>>>> > >>>>> Since I'm not an experienced user in Tomcat, I wonder which > >>>>> implementation alternatives do you recommend for running my > >>>>> external application. I'm trying to avoid launch a new os process > >>>>> from java since I need the result of that process, so in this way > >>>>> I've to deal communicating two processes (may be using serializable > >>>>> objects using sockets). > >>>> > >>>> So, is this other program a Java program? Since you said > >>>> "serializable" you probably are talking about running another Java > >>>> "program". > >>>> > >>>> What makes this "external" "program" non-multithreaded? Is it actually > >>>> not threadsafe? > >>>> > >>>> If you can't run it in the same process as Tomcat, then you'll have to > >>>> either use Runtime.exec or some type of wrapper around it -- or have > >>>> that process running completely separately (as a daemon) and connect > >>>> to it via sockets. Anything else requires native code, which you > >>>> definitely don't want. > >>> > >>> > >>> My external application is a java application that uses java wrapper > >> (using > >>> JNI) for GLPK (written in ANSI C) (http://www.gnu.org/s/glpk/), and > >> GLPK is > >>> not threadsafe. Yes, I will consider those alternatives, executing a > new > >>> process when I receive the request (Runtime.exec) and a separated > deamon > >>> receiving requests launching those processes. > >> > >> Can you not import the application Jars and just interact with them > >> directly then? Why do you have to interact with it via system process? > >> > > > > If I do that, due to glpk is not threadsafe, a call to a method can crash > > tomcat. > > I don't know what glpk does, can you explain?
glpk is a gnu library to solving some kind of mathematical problems http://www.gnu.org/software/glpk/ You can use the library in c, and there exist wrappers for java, python and other programming languages > > I think you may be over thinking the thread safety issue. > > If multiple threads can't access the instances of the thing, thread > safety is not an issue. > > If the entire code block was instantiated inside a Servlet doGet > method with no external exposure or external scope, there is no > problem. > > Do you know why it is not thread safe? > I know about some problems related to process memory allocation/deallocation because I've experienced them. The documentation says that is not thread safe. Why do you think that I'm over thinking thread safety issue?
