| jnull {rJava} | R Documentation |
.jnull returns a null reference of a specified class
type.
.jnull(class = "java/lang/Object")
class |
fully qualified target class name in JNI notation
(e.g. "java/lang/String"). |
This function is necesary if null is to be passed as an
argument of .jcall or .jnew, in order to be
able to find the correct method/constructor.
Example: given the following method definitions of the class A:
Calling .jcall("A",,"run",NULL) is ambiguous, because it is
unclear which method is to be used. Therefore rJava requires class
information with each argument to .jcall. If we wanted
to run the String-version, we could use .jcall("A",,"run",.jnull("java/lang/String")).
Returns a Java object reference (jobjRef) of a null
object having the specified object class.
## Not run:
.jcall("java/lang/System","I","identityHashCode",.jnull())
## End(Not run)