Check JVM for pending expections and clear them
.jcheck checks the Java VM for any pending exceptions and
.jcheck(silent = FALSE)
- If set to
FALSEthen Java is instructed to print the exception on
stderr. Note that Windows Rgui doesn't show
stderrso it will not appear there (the printing is done internally in the JVM, so there is no
The exception handling is currently rather crude as there is no way to obtain programmatical access to thrown exceptions. In addition, some internal code clears exceptions (e.g. after some failed JNI calls), so it may occasionally not behave as expected. However, this applies only to code called as a side-effect (such as when converting an object), so exceptions thrown as a result of a directly invoked code are not affected.
Nevertheless more elaborate exception handling system is planned for rJava 0.5.
TRUEif an exception occurred or
# we try to create a bogus object and # instruct .jnew to not clear the exception v <- .jnew("foo/bar", check=FALSE) # expect TRUE result here because the class doesn't exist print(.jcheck(silent=TRUE)) # next invocation will be FALSE because the exception is now cleared print(.jcheck(silent=TRUE))