Hi, You could ask the author or post an issue here .( https://github.com/s-u/rJava) I had faced a problem and I got a response from him.
In my case I am streaming JVM data and this( http://www.openanalytics.eu/r-service-bus) may be a better idea. I haven't still tried this. Thanks, Mohan On Fri, Sep 26, 2014 at 5:25 PM, Benoît Thiébault <thieba...@artenum.com> wrote: > Hi everyone, > > I want to call a Java application from R and have encountered some > problems with the way rJava deals with the system class loader. > > To run my application, I use the following R script: > > > library(rJava) > > .jinit() > > .jaddClassPath("myApp.jar") > > rWrapper <- .jnew("org/test/RWrapper") > > .jcall(rWrapper,"V","start") > > My Java application has a plugins loading mechanism that uses a specific > PluginClassLoader to load plugins stored in additional JAR files (e.g. > plugin.jar). This PluginClassLoader is programed so that it knows and loads > the plugins JARs. As any Java classloader, it is a child of the system > class loader. > > Finally, plugins not only use classes stored in their plugin.jar file, > they also depend on classes contained in the main myApp.jar file (the > Plugin interface is for example defined in the myApp.far) > > In a pure Java environment, myApp.jar is known from the system class > loader (it is in the classpath) and thus the PluginClassLoader can load > classes from the plugin (it knows both about the plugin.jar and the > myApp.jar files) > > In the R context however, using the above script, its the RJavaClassLoader > that knows about the myApp.jar file. The org.test.RWrapper class is > instatiated by the RJavaClassLoader. The system class loader however does > not know about myApp.jar anymore. Neither does the PluginClassLoader. So > when the PluginClassLoader loads a plugin class, it can only load classes > that are in the plugin.jar file and as soon as a class from the myApp.jar > file is required by the plugin, it crashes with a > java.lang.NoClassDefFoundError message. > > My question is: how can I force rJava to load the classpath in the system > classloader and not only in the RJavaClassLoader? > > I cannot make the PluginClassLoader know the RJavaClassLoader as my > application also has to run in a non-R environment. > > Thanks for your time, > > Kind regards, > > Ben > ______________________________________________ > R-help@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide > http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. > [[alternative HTML version deleted]] ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.