scalaPushRegister: Register Functions to Push and Pull Between R and Scala

In rscala: Bridge Between 'R' and 'Scala' with Callbacks

Register Functions to Push and Pull Between R and Scala

Description

The 'rscala' package provides support for serializing objects between R and Scala. These registration functions allows additional, more-specialized push and pull methods to be added. Package developers may want to call these registration functions in the package's .onLoad function.

Usage

scalaPushRegister(pusher, method, bridge = scalaFindBridge())

scalaPullRegister(puller, method, bridge = scalaFindBridge())

Arguments

pusher	A function whose first two arguments are as shown in the example below. Other arguments can be used as additional arguments.
method	A string giving the name of the specific 'push' or 'pull' method.
bridge	A Scala bridge.
puller	A function whose first two arguments are as shown in the example below. Other arguments can be used as additional arguments.

See Also

scalaPush, scalaPull

Examples

s <- scala()

name <- "Grace"
nameAsRObject <- scalaPush(name,"generic")   # Basic serialization
scalaType(nameAsRObject)
identical(name,scalaPull(nameAsRObject,"generic"))

scalaPush.character <- function(x, bridge) {
  if ( is.character(x) && ( length(x) == 1L ) ) bridge(x=x) ^ 'x'
  else stop("'x' should be a character vector.")
}
scalaPushRegister(scalaPush.character, "character")
nameAsString <- scalaPush(name, "character", s)    # More specific serialization
scalaType(nameAsString)

scalaPull.character <- function(reference, bridge) {
  if ( scalaType(reference) == "String" ) reference$toString()
  else stop("'reference' should be a 'String'.")
}
scalaPullRegister(scalaPull.character, "character")
identical(name,scalaPull(nameAsString,"character"))

close(s)

rscala documentation built on Aug. 15, 2023, 9:07 a.m.