[java-atk-wrapper] HACKING: Add some convention and style info

[Magdalen Berns <mberns src gnome org>]

commit 01abf43140910354c2cbde41b7b8b7b67c0f41b6
Author: Magdalen Berns <m berns thismagpie com>
Date:   Sun Mar 1 22:39:40 2015 +0000

    HACKING: Add some convention and style info
    
    Bug: https://bugzilla.gnome.org/show_bug.cgi?id=745386

 HACKING |   16 ++++++++++++++++
 1 files changed, 16 insertions(+), 0 deletions(-)
---
diff --git a/HACKING b/HACKING
index 34c133d..30d64fc 100644
--- a/HACKING
+++ b/HACKING
@@ -102,3 +102,19 @@ Value Interface:
   set_current_value      -   use set_value instead
   get_minimum_increment  -   use get_increment instead
 
+Conventions for Writing Java ATK Wrapper Code
+---------------------------------------------
+
+Spaces instead of tabs.
+Two spaces per indent.
+
+JNI error messages are in the form:
+  g_warning("\n *** method calling instance: instance == NULL *** \n");
+
+Other Things to Keep in Mind
+----------------------------
+
+The jint object is mapped to C's long which is always at least 32 bits), instead
+of of C's int (which could be 16 bits). The resource for glib types can be
+found at <https://developer.gnome.org/glib/stable/glib-Basic-Types.html>
+