1.
JRuby
Webwith JRuby
Enterprise Web Application Development
2010 12 4 Akasaka.rb
Photo by Michael Pick

2.
Photo by Koichiro Ohba

3.
Rubyist
Struts

4.
Front Controller
ActionServlet RequestProcessor Action
processActionPerform
process
execute

5.
Front Controller
ActionServlet RequestProcessor Action
processActionPerform
process
execute

6.
JRubyRequestController
Struts RequestProcessor
Ruby
class RubyActionRequestProcessor
def process_action_form req, res, mapping
# do something
end
def process_action_perform req, res, action, form, mapping
# do something
end
end

7.
JRubyRequestController.java
public class JRubyRequestProcessor
extends RequestProcessor {
...
@Override
public void init(ActionServlet servlet,
ModuleConfig moduleConfig)
throws ServletException {
super.init(servlet, moduleConfig);
...

8.
struts-config.xml
<struts-config>
...
<controller
processorClass="n.r.s.JRubyRequestProcessor">
<set-property
key="scriptPath"
value="/WEB-INF/request-processor.rb"
/>
</controller>
...
</struts-config>

9.
JRubyRequestController#init()
container = new ScriptingContainer(
LocalContextScope.THREADSAFE
);
•
• LocalContextScope.THREADSAFE
Ruby

10.
JRubyRequestController#init()
container.put("SERVLET_CONTEXT",
servlet.getServletContext());
• ServletContext
SERVLET_CONTEXT

11.
JRubyRequestController#init()
String path =
moduleConfig.getControllerConfig()
.getProperty("scriptPath");
InputStream stream =
servlet.getServletContext()
.getResourceAsStream(path);
EmbedEvalUnit unit =
container.parse(stream, path);
requestProcessor = unit.run();
• scriptPath
requestProcessor

12.
JRubyRequestController#init()
String[] names =
container.callMethod(requestProcessor,
"public_methods",
false,
String[].class);
supportedMethods =
new HashSet<String>(Arrays.asList(names));
• requestProcessor
public_methods false

13.
JRubyRequestController.java
@Override
protected ActionForward process...(
HttpServletRequest request...) throws ...{
if (supportedMethods.contains("process...")){
return container.callMethod(
requestProcessor,
"process...",
new Object[] { request, ... },
ActionForward.class);
} else {
return super.process...
}
...

14.
requestProcessor
JRubyRequsetProcessor
:IRubyObject
processActionPerform
process_action_perform
Ruby

15.
JRubyRequestProcessor

16.
SinatraRequestProcessor
class SinatraRequestProcessor
def initialize
@app = SinatraHelloAction.new
end
def process req, res
servlet_env = ServletRackEnvironment.new req
env = Rack::Handler::LazyEnv.new servlet_env
status, header, body = @app.call env.to_hash
res.setStatus(status)
header.each do |k, v|
res.setHeader(k, v)
end
out = res.getOutputStream
out.print(body.join)
end
end

17.
Happy Hacking!
and
Good Carling!