Oracle Certified Master, Java EE 5 Enterprise Architect OCMJEA (SCEA5) part1 passed

On 29 October 2011 I passed OCMJEA part 1, it was quite tricky exam but I enjoy it and everything went fine, I also completed required hands on training and subscribed for part 2 assignment which I must complete until may 2012.
I'm very happy now:).

Using thread pool starting from java5

import java.util.concurrent.ExecutorService;
import java.util.concurrent.ScheduledThreadPoolExecutor;

/**
 * Processing jobs thread pool
 */
public class ProcessingJobExecutorService {
    private static ProcessingJobExecutorService _instance =null;
    private ExecutorService executorService;
   
    private ProcessingJobExecutorService(){
        executorService = new ScheduledThreadPoolExecutor(500);   
    }
   
    public static ProcessingJobExecutorService getInstance(){
        if(_instance==null){
            _instance=new ProcessingJobExecutorService();
        }
        return _instance;
    }
    public void execute (Runnable r){
        executorService.execute(r);
       
    }

}

Developing Applications for the Java EE 6 Platform Oracle training

This week I completed this training from Oracle. It was a pleasure to listen and do some exercises with Netbeans and Glassfish. The course was quite expensive but I chose it for mandatory course attendance requirement in case of jee architect certification.

Wicket: Add tabindex from java code

Read this forum

Marcus Vitruvius Pollio

Read this wiki !

java to javascript in wicket

//

//---- code in wicket page constructor ----
//internationalised message to javascript visible in html page
 String contributor = "";
 add(new StringHeaderContributor(contributor));
//

Domain driven vs service oriented architecture/design

Domain driven design and service oriented design are opposite approaches, while service oriented approach is more stateless (SOA) and more procedural programming like, the domain driven approach is more stateful and object oriented.
The best practices in each case tend to become anti-patterns in the other case.

md5 in java whitout reading file in a buffer

import java.io.BufferedReader;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.PrintStream;
import java.util.Scanner;


public class MD5 {

 /**
  * @param args
  * @throws Exception 
  */
 public static void main(String[] args) throws Exception {
    String[] cmd = new String[]{"md5sum","/home/user/workspace/project/buildfile"};
       ProcessBuilder pb = new ProcessBuilder(cmd);
       Process p = pb.start();
       BufferedReader br = new BufferedReader(new InputStreamReader(p.getInputStream()));  
       StringBuffer sb = new StringBuffer();  
       String line;  
       while ((line = br.readLine()) != null) {  
         sb.append(line).append("\n");  
       }  
       String answer = sb.toString();  
       
       int val = p.waitFor();
       String md5 ="";
       if(val == 0){
        Scanner s = new Scanner(answer);
        if(s.hasNext()){
         md5 = s.next();
         System.out.println(md5);
        }
       }else{
        System.out.println("Error executing command md5sum");
       }
      
 }
 

}

JQuery - select html elements with id starting with given string

//select all divs with id starting with 'jpassword'



 $("div[id^='jpassword']").style.display = 'none';

Exit on ESC in Wicket ModalWindow

//Every modal dialog will extend this class

public class ModalPanelContainer extends ModalWindow implements IHeaderContributor {



    //the magic is in this method

    @Override

    public void show(final AjaxRequestTarget target) {

        if (!isShown()) {

            final AppendingStringBuffer buffer = new AppendingStringBuffer(500);

            buffer.append("function mwClose(ev) {\n" +

                    "var code = ev.keyCode || ev.which;\n" +

                        "if (code == 27) { " +

                            getCloseJavacript() +

                        "};" +

                    "}");

            buffer.append("jQuery(document).keypress(mwClose);\n");

            target.appendJavascript(buffer.toString());

        }

        super.show(target);

    } 







}

Custom 404 error page in Wicket

In web.xml you must have something like this:

	WicketFilter

	org.apache.wicket.protocol.http.WicketFilter

	

	

		applicationClassName

		com.yourproject.FrontendWebApplication

	





	WicketFilter

	/*

	REQUEST

	ERROR





	404

	/error404

After this create a page with mounting point "errror404".

That's it.