Installing s3fs on Mac

I'm not a Mac guy but was instructed to do so. Ran through a few web site, try to install pkg-config, fuse, glib, ... ... and end up with the simplest solution.

Step 1:
Install MacPorts from http://www.macports.org/

Step 2:
Install s3fs with MacPorts.
port install s3fs

Done.
Thanks to MacPorts

Manually Sort an ArrayList in Java

Just like to paste this code:

        List sorted = new ArrayList();
        RackPosition temp = null;
        int remove_index = -1;

        while(original.size() > 0) {    
            temp = original.get(0);
            for (int i = 0; i < original.size(); i++ ) {
                RackPosition rp2 = original.get(i);
                if(temp.getPositionNumber().compareTo(rp2.getPositionNumber()) > 0) {
                    temp = rp2;
                    remove_index = i;
                }
            }
            System.out.println("Adding " + temp.getPositionNumber());
            sorted.add(temp);
//          original.remove(temp);
            if(remove_index >= 0) {
                original.remove(remove_index);
            }
            remove_index = 0;
        }

Generate S3 Pre-signed URL in Java

I googled, not happy, so post it myself.

import java.util.Calendar;
import java.util.Date;

import com.amazonaws.HttpMethod;
import com.amazonaws.auth.BasicAWSCredentials;
import com.amazonaws.services.s3.AmazonS3;
import com.amazonaws.services.s3.AmazonS3Client;

public class PreSignURLGenerator {

    private final static String BUCKET_NAME = "this-is-not-porn";
    private final static String FILE_NAME = "not-porn-media-files/0146ce52-bbd5-4998-9378-35c20ece0000.jpg";
    private final static String ACCESS_KEY = "not-telling-you";
    private final static String SECRET_KEY = "it-s-a-secret";

    /**
     * @param args
     */
    public static void main(String[] args) {
        Calendar cal = Calendar.getInstance();
        cal.add(Calendar.SECOND, 1000);
        Date expDate = cal.getTime();
        try {
            BasicAWSCredentials cre = new BasicAWSCredentials(ACCESS_KEY, SECRET_KEY);
            AmazonS3 s3 = new AmazonS3Client(cre);
     String url = s3.generatePresignedUrl(BUCKET_NAME, FILE_NAME, expDate, HttpMethod.GET).toString();
            System.out.println(url);
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

FYI:

and required access to Internet/AWS.

Do feedback if you really like this post.

jBPM - How to trace a lifecycle of a process

Just need to add a ProcesEventListener() to the ksession.

KnowledgeBase kbase = readKnowledgeBase();
StatefulKnowledgeSession ksession = kbase.newStatefulKnowledgeSession();

CustomProcessEventListener customProcessEventListener = new CustomProcessEventListener();
ksession.addEventListener(customProcessEventListener);
...
...

ksession.startProcess("com.sample.MyTaskFlow", params);

And here is the sample CustomProcessEventListener();

private static class CustomProcessEventListener implements ProcessEventListener {

 @Override
 public void afterNodeLeft(ProcessNodeLeftEvent arg0) {
  // TODO Auto-generated method stub
  
 }

 @Override
 public void afterNodeTriggered(ProcessNodeTriggeredEvent arg0) {
  // TODO Auto-generated method stub
 }

 @Override
 public void afterProcessCompleted(ProcessCompletedEvent arg0) {
  // TODO Auto-generated method stub
  logger.debug("Process has completed.");
  System.exit(0);
 }

 @Override
 public void afterProcessStarted(ProcessStartedEvent arg0) {
  // TODO Auto-generated method stub
 }

 @Override
 public void afterVariableChanged(ProcessVariableChangedEvent arg0) {
  // TODO Auto-generated method stub
   
  }

 @Override
 public void beforeNodeLeft(ProcessNodeLeftEvent arg0) {
  // TODO Auto-generated method stub
   
 }

 @Override
 public void beforeNodeTriggered(ProcessNodeTriggeredEvent arg0) {
  // TODO Auto-generated method stub
   
 }

 @Override
 public void beforeProcessCompleted(ProcessCompletedEvent arg0) {
  // TODO Auto-generated method stub
  logger.debug("Process is going to be completed.");
 }

 @Override
 public void beforeProcessStarted(ProcessStartedEvent arg0) {
  // TODO Auto-generated method stub
  
 }

 @Override
 public void beforeVariableChanged(ProcessVariableChangedEvent arg0) {
  // TODO Auto-generated method stub
  
 }
 
}

As you can see, you can do many things on every stage of a process.

Drools again, example for beginner

Who would foresee that I will get my hand dirty again with drools? Well, after 13 months, here I am, looking at drools, again... now with jbpm too.
Anyway, it was good. Got better understanding about it and yeah, as usual, share.

I successfully made this:

I am not posting the codes here, you can request for it if you want.

The first process flow (can be in .rf or .bpmn) shows how to use Script Tasks. In the "Question" script, I ran these:

System.out.println("Who is the smartest man in the world?");

java.io.BufferedReader br = new java.io.BufferedReader(new 

                         java.io.InputStreamReader(System.in));

String name = null;

try {

name = br.readLine();

} catch (java.io.IOException e) {

System.out.println("Error!");

}

kcontext.setVariable("smart_guy", name);

The gateway after the "Question" script I check for this:

return smart_guy.equals("frank");

The "Error message" script just print error message. I ran the process.

ksession.startProcess("interactiveJava");

It will keep on asking you who the question until you say "frank". Pretty basic but it gives you better understand about how things run.

Here is the sample output.

The learning issues here will be:

• Define variable "smart_guy" in the flow/process.

• In the "Question" script, we set the user input to the process variable. 

     kcontext.setVariable("smart_guy", name);

• In the gateway constraint:

     return smart_guy.equals("frank");

For beginners, you should try it out your self.

Many thanks to Drools/jBPM development team and the community for their hard work. Many helpful resources are now available online compare to last year.

Can you cook an egg in your car? Yes you can!

Today I ran a very crazy experiment with my car. Because it was very very hot today, 40°. So I want to see if I can cook an egg inside the car dashboard. And here is the result.
Too bad I didn't record the temperature inside the car, but it IS hot enough to cook an egg.

Who sucks?

When googling and found ... always annoys me. I learned it from the hard way, so I just want to present a fairer view and give you another perspective.



Plain: google search the keyword
Sucks: adds a ' sucks' at the end of the keyword
Great: adds a ' great' at the end of the keyword

I'll let you guys do your own conclusion.