OCaml <-> Java Interface

Interop with Java

Provides a low-level, unsafe interface between OCaml and Java and high-level, typed OCaml interface using a PPX rewriter.

This is still a work in progress.

Heavily inspired by camljava

Example

A simple example that use the Java's DateFormat class

let () = Java.init [| "-Djava.class.path=bin/ocaml-java.jar" |]

class%java date "java.util.Date" = object end

class%java format "java.text.Format" = object end

class%java date_format "java.text.DateFormat" =
object
	inherit format
	method format : date -> string = "format"
	method parse : string -> date = "parse"
	method [@static] get_instance : date_format = "getInstance"
end

let () =
	let format = Date_format.get_instance () in
	let date_string = "09/13/1996 9:45 AM GMT+1" in
	let date = Date_format.parse format date_string in
	print_endline (Date_format.format format date)

Example jbuild file:

(jbuild_version 1)
(executable
 ((name test)
  (libraries (ocamljava.camljava))
  (preprocess (pps (ocamljava-ppx)))))

Documentation

Modules interfaces:

• Java
• Jcall, unsafe low-level api for calling Java methods
• Jclass to query class/method/field handles
• Jarray to manipulate Java arrays
• Jrunnable to create and run Runnable objects
• Jthrowable to throw and access Java exceptions

Ppx: README

Java side: Caml