foo.rb

# `javac InterfaceA.java InterfaceB.java`

require "java"
require "InterfaceA"
require "InterfaceB"

class Foo
  include Java::Foo::InterfaceA
  include Java::Foo::InterfaceB
  
  def a
    p :a
  end
  
  def b
    p :b
  end
  
end


require "test/unit"

class TestLibraryFileName < Test::Unit::TestCase
  def test_case_name
    assert false
  end
end

p $!  # => #<TypeError: <=> requires JavaClass (NilClass given)>
p $@  # => ["foo.rb:12:in `append_features'", "foo.rb:12"]

InterfaceA.java

package foo;

public interface InterfaceA {
	void a();
}

InterfaceB.java

package foo;

public interface InterfaceB {
	void b();
}