Initialize Java VM
.jinit initializes the Java Virtual Machine (JVM). This
function must be called before any rJava functions can be used.
.jinit(classpath = NULL, parameters = getOption("java.parameters"), ..., silent = FALSE)
- Any additional classes to include in the Java class
paths (i.e. locations of Java classes to use). This path will be
prepended to paths specified in the
- character vector of parameters to be passed to the virtual machine. They are implementation dependent and apply to JDK version 1.2 or higher only. Please note that each parameter must be in a separate element of the array, you cannot use a
- Other optional Java initialization parameters (implementation-dependent).
- If set to
TRUEno warnings are issued.
Stating with version 0.3-8 rJava is now capable of modifying the class
path on the fly for certain Sun-based Java virtual machines, even when
attaching to an existing VM. However, this is done by exploiting the
way ClassLoader is implemented and may fail in the future. In general
it is officially not possible to change the class path of a running
At any rate, it is impossible to change any other VM parameters of a
running VM, so when using
.jinit in a package, be generous with
limits and don't use VM parameters to unnecessarily restrict
resources. Also you should always respect the "java.parameters" option
and update only setting if you really must.
- The return value is an integer specifying whether and how the VM was initialized. Negative values indicate failure, zero denotes successful initialization and positive values signify partially successful initilization (i.e. the VM is up, but parameters or class path could not be set due to an existing or incompatible VM).
## use "myClasses.jar" as the class path .jinit(classpath="myClasses.jar")