ob-java.el: Allow non-public classes

* lisp/ob-java.el: Don't require class definitions to be declared
public.

* testing/lisp/test-ob-java.el: Add test with non-public class.

lisp/ob-java.el

@@ -125,22 +125,22 @@
 Look through BODY for the package and class.  If found, put them
 together into a fully qualified class name and return.  Else just
 return class name.  If that isn't found either, default to Main."
-  (let ((package (if (string-match "package \\\([^ ]*\\\);" body)
+  (let ((package (if (string-match org-babel-java--package-re body)
                      (match-string 1 body)))
-        (class (if (string-match "public class \\\([^ \n]*\\\)" body)
+        (class (if (string-match org-babel-java--class-re body)
                    (match-string 1 body))))
     (or (and package class (concat package "." class))
         (and class class)
         (and package (concat package ".Main"))
         "Main")))
 
-(defconst org-babel-java--package-re "^[[:space:]]*package .*;$"
+(defconst org-babel-java--package-re "^[[:space:]]*package[[:space:]]+\\\([[:alnum:]_\.]+\\\);$"
   "Regexp for the package statement.")
-(defconst org-babel-java--imports-re "^[[:space:]]*import .*;$"
+(defconst org-babel-java--imports-re "^[[:space:]]*import[[:space:]]+\\\([[:alnum:]_\.]+\\\);$"
   "Regexp for import statements.")
-(defconst org-babel-java--class-re "^public class [[:alnum:]_]+[[:space:]]*\n?[[:space:]]*{"
+(defconst org-babel-java--class-re "^[[:space:]]*\\\(?:public[[:space:]]+\\\)?class[[:space:]]+\\\([[:alnum:]_]+\\\)[[:space:]]*\n?[[:space:]]*{"
   "Regexp for the class declaration.")
-(defconst org-babel-java--main-re "public static void main(String\\(?:\\[]\\)? args\\(?:\\[]\\)?).*\n?[[:space:]]*{"
+(defconst org-babel-java--main-re "public static void main(String\\\(?:\\[]\\\)?[[:space:]]+[^ ]+\\\(?:\\[]\\\)?).*\n?[[:space:]]*{"
   "Regexp for the main method declaration.")
 (defconst org-babel-java--any-method-re "public .*(.*).*\n?[[:space:]]*{"
   "Regexp for any method.")

testing/lisp/test-ob-java.el

@@ -137,6 +137,18 @@ public class Simple {
 #+end_src"
    (should (string= "42" (org-babel-execute-src-block)))))
 
+(ert-deftest ob-java/simple-with-non-public-class ()
+  "Hello world program that defines a non-public class."
+  (org-test-with-temp-text
+      "#+begin_src java :results output silent
+class Simple {
+    public static void main(String[] args) {
+        System.out.print(42);
+    }
+}
+#+end_src"
+   (should (string= "42" (org-babel-execute-src-block)))))
+
 (ert-deftest ob-java/simple-with-class-and-package ()
   "Hello world program that defines a class and package."
   (org-test-with-temp-text