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## S4 classes (jobjRef is re-defined in .First.lib to contain valid jobj)
#' java object reference
setClass("jobjRef", representation(jobj="externalptr", jclass="character"),
prototype=list(jobj=NULL, jclass="java/lang/Object"))
#' rugged arrays
setClass("jarrayRef", representation("jobjRef", jsig="character"))
#' rectangular java arrays double[][] d = new double[m][n]
setClass("jrectRef",
representation("jarrayRef", dimension="integer" ) )
# we extend array here so that we can keep dimensions
# in the helper functions below, the storage mode is
# set when the objects are built
# TODO: maybe an initialize method is needed here
# TODO: maybe a validate method is needed here as well
setClass("jfloat", representation("array" ) )
setClass("jlong", representation("array" ) )
setClass("jbyte", representation("array" ) )
setClass("jshort", representation("array" ) )
setClass("jchar", representation("array" ) )
# there is no way to distinguish between double and float in R, so we need to mark floats specifically
.jfloat <- function(x) {
storage.mode( x ) <- "double"
new("jfloat", x )
}
# the same applies to long
.jlong <- function(x) {
storage.mode( x ) <- "double"
new("jlong", x)
}
# and byte
.jbyte <- function(x) {
storage.mode( x ) <- "integer"
new("jbyte", x)
}
# and short
.jshort <- function(x){
storage.mode( x ) <- "integer"
new("jshort", x)
}
# and char (experimental)
.jchar <- function(x){
if (is.character(x)) {
if (length(x) != 1L || is.na(x))
stop(".jchar() supports only (non-NA) character vectors of length one (aka strings)")
## use Java to actually do the conversion
x <- .jcall(.jnew("java.lang.String", x), "[C", "toCharArray")
}
storage.mode( x ) <- "integer"
new("jchar", x)
}
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