don't change java.parameters option, but set defaults in .jinit instead (closes #341)

Author: s-u

R/jfirst.R

@@ -46,10 +46,6 @@
   for (x in .delayed.variables) assign(x, NULL, .env)
   assign(".jniInitialized", FALSE, .env)
 
-  # default JVM initialization parameters
-  if (is.null(getOption("java.parameters")))
-    options("java.parameters"="-Xmx512m")
-  
   ## S4 classes update - all classes are created earlier in classes.R, but jobjRef's prototype is only valid after the dylib is loaded
   setClass("jobjRef", representation(jobj="externalptr", jclass="character"), prototype=list(jobj=.jzeroRef, jclass="java/lang/Object"), where=.env)  
 }

R/jinit.R

@@ -10,7 +10,7 @@
     .Call(RJava_needs_init)
 
 ## initialization
-.jinit <- function(classpath=NULL, parameters=getOption("java.parameters"), ..., silent=FALSE, force.init=FALSE) {
+.jinit <- function(classpath=NULL, parameters=getOption("java.parameters", NA), ..., silent=FALSE, force.init=FALSE) {
   running.classpath <- character()
   if (!.need.init()) {
     running.classpath <- .jclassPath()
@@ -23,6 +23,21 @@
     }
   }
 
+  # default JVM initialization parameters
+  # Up until 1.0-12 jfirst (=onLoad) set java.parameters to -Xmx512m to increase the heap
+  # size, so parameters was always -Xmx512m unless the user set java.parameters or parameters.
+  # We now leave the java.parameters alone and only set the default heap size if
+  # java.parameters is not set -- with mostly the same effect.
+  # (NB: JVMs have changed the default from 256Mb to 25% of available memory in some cases,
+  # thus the default is becoming less important nowadays.)
+  # We also increase the default heap size since machines using R are unlikely
+  # to be starved for RAM. Note that the meaning of NULL has changed to "none"
+  # since 1.0-13.
+  if (any(is.na(parameters)))
+      parameters <- "-Xmx1g"
+  if (is.null(parameters))
+      parameters <- character()
+
   ## determine path separator
   path.sep <- .Platform$path.sep
 

man/jinit.Rd

@@ -11,8 +11,8 @@
   \code{.jvmState() returns the state of the current JVM.}
 }
 \usage{
-.jinit(classpath = NULL, parameters = getOption("java.parameters"), ...,
-silent = FALSE, force.init = FALSE)
+.jinit(classpath = NULL, parameters = getOption("java.parameters", NA), ...,
+       silent = FALSE, force.init = FALSE)
 .jvmState()
 }
 \arguments{
@@ -25,7 +25,10 @@ silent = FALSE, force.init = FALSE)
     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
-    space-separated string with multiple parameters.}
+    space-separated string with multiple parameters. The value of
+    \code{NA} means "use rJava default" which is \code{"-Xmx1g"}
+    currently. \code{NULL} is equivalent to \code{character()}.
+  }
   \item{...}{Other optional Java initialization parameters (implementation-dependent).}
   \item{silent}{If set to \code{TRUE} no warnings are issued.}
   \item{force.init}{If set to \code{TRUE} JVM is re-initialized even if
@@ -89,15 +92,17 @@ silent = FALSE, force.init = FALSE)
   rare and problematic in either case. Behavior of rJava functions other
   than \code{.jinit} and \code{.jvmState} is undefined unless
   \code{.jvmState()$initialized} is \code{TRUE}.
+
+  NOTE: \code{.jinit()} can be called implicitly by other functions such
+  as \code{\link{.jpackage}} or \code{\link{J}}.
 }
 \seealso{
   \code{\link{.jpackage}}
 }
 \examples{
 \dontrun{
-## set heap size limit to 512MB (see java -X) and
-## use "myClasses.jar" as the class path
-.jinit(classpath="myClasses.jar", parameters="-Xmx512m")
+## set heap size limit to 512MB (see java -X)
+.jinit(parameters="-Xmx512m")
 .jvmState()
 }
 }