Let your mind go and your body will follow

Excellent Netty introduction

2011-07-19T05:31:00.000-07:00

I'm trying Netty these days and I find it very nice to work with.

I came upon this fine introduction about Netty.

java.lang.OutOfMemoryError: PermGen space problem

2011-06-21T07:04:00.001-07:00

We had a few these days.
Came upon this nice article on how to solve them.
http://blogs.oracle.com/fkieviet/entry/how_to_fix_the_dreaded

In the meantime we just increased it.

JConsole on a remote machine

2010-06-16T02:52:00.000-07:00

If you want to monitor your app on a remote machine use this when you start it:

-Dcom.sun.management.jmxremote
-Dcom.sun.management.jmxremote.port=8888
-Dcom.sun.management.jmxremote.ssl=false
-Dcom.sun.management.jmxremote.authenticate=false
-Djava.rmi.server.hostname=putYourAppRemoteIPHere

Funny 404 page

2010-03-25T03:19:00.000-07:00

Turn your sound on.
System is down!

More nice thoughts

2010-03-23T04:10:00.000-07:00

why the lucky stiff

From Drop Box

Blaise Aguera y Arcas demos augmented-reality maps

2010-02-19T03:15:00.000-08:00

One more

2010-02-10T06:39:00.000-08:00

"It is not knowledge, but the act of learning, not possession but the act of getting there, which grants the greatest enjoyment. When I have clarified and exhausted a subject, then I turn away from it, in order to go into darkness again; the never-satisfied man is so strange if he has completed a structure, then it is not in order to dwell in it peacefully, but in order to begin another. I imagine the world conqueror must feel thus, who, after one kingdom is scarcely conquered, stretches out his arms for others."

—KARL FRIEDRICH GAUSS, Letter to Bolyai, 1808.

The Best One From Jazoon 09

2010-02-09T01:45:00.000-08:00

Really inspiring talk, not only for programmers.

Nice one about politicians

2010-01-27T04:58:00.000-08:00

Sink A Ship included in the Softpedia Mac OS software database

2010-01-10T00:10:00.000-08:00

Few months ago I got mail from softpedia saying:

"Congratulations,

Sink A Ship, one of your products, has been added to Softpedia's database
of software programs for Mac OS...
...We are impressed with the quality of your
product and encourage you to keep these high standards in the future..."

:)

Although it's simple game, the feeling is nice when you get this kind of email. I didn't write to softpedia and the only places I wrote about the game is here, on blogspot, and on jfxstudio, place for sharing JavaFX experiments.

My experiment with JavaFX turned out to be interesting for kids these days just like the game which "Sink a ship" was based on, "Seawolf", was interesting for me and my sister when we were kids.

Well, show it to your kids and share some ideas for improvements.

My better half, my <3 made me work harder to make the game looks like this. I wanted to try JavaFX and my game would look like a bunch of triangles running around.

How to set Java memory usage of Tomcat 4.1 started as a Windows service

2009-12-23T05:54:00.000-08:00

If you try to set Java parameters -Xms or -Xmx in catalina.bat it would work only if you start Tomcat with startup.bat.
If you want to start Tomcat as a service you must dig through registry.
Taken from jguru.

1. Open up the registry (Run -> Regedit)

2. Find the entry for your Tomcat service entry. Either do a search for the service name in the registry or navigate to:
HKEY_LOCAL_MACHINE.SYSTEM.CurrentControlSet.Services.Apache Tomcat 4.1.Parameters

3. You should see several numbered "JVM Option Number" parameters

4. Add two new "String Value" parameters, succeeding the ordinal count of those already there, in my case 4 and 5

5. Add your arguments. I used: -Xms128m and -Xmx128m

6. Modify the JVM Option Count accordingly.

7. Restart your service.

Punished By Rewards

2009-10-22T06:24:00.000-07:00

I'm interested in reading:
Punished By Rewards: The Trouble with Gold Stars, Incentive Plans, A's, Praise, and Other Bribes

Can't find it in bookstores and I have trouble ordering it from Amazon since my country is not in love with the rest of the world!

Interesting review from Yolanda on Amazon:
"Rewards fail for five reasons.
- First, rewards punish and control by seduction. The failure to win a reward or the threat to remove a reward is functionally identical to the threat to employ a punishment.
- Second, rewards rupture relationships both vertically (student/teacher) and horizontally (student/student). Both rewards and punishment are really about someone maintaining power and control over another and they induce a behavior pattern whereby the subordinate tries to curry favor and impress the rewarder rather than encourage a relationship of trust and openness. Also, rewards lead to destructive competition.
- Third, employing rewards can change superficial behavior effectively, but it ignores the underlying reasons for the problem behavior and so does not effect long-term change. Rewards are not solutions, they are gimmicks, shortcuts, quick fixes that mask problems.
- Fourth, rewards discourage risk taking, creativity, and taking on challenges because the task is now just something that stands in the way of gaining the prize. - Finally, and most tragically, rewards change the way people approach the task. To reward someone for something that many find intrinsically interesting and enjoy doing is to destroy motivation. For example, the Pizza Hut "Book It" reading incentive and summer library reading incentive programs are, according to Kohn, very destructive. Reading is presented not as a pleasurable experience, but as something one has to be bribed to do with a food reward or other token."

Exporting pdf from Jasper (problem with unicode)

2009-10-13T02:49:00.000-07:00

In my other post I described how to export from Jasper.

There is potential problem if you need to use unicode fonts.

In order to export Jasper to pdf, you need TrueType font that has all the characters that your exported pdf is going to contain.
I had a lot of trouble to find free font that has all the glyphs I need.
Found it on myfonts.

euro-sans-pro

All you need to write in jrxml file is:


<font pdffontname="myPathToFonts\fontFileName.ttf" pdfencoding="Identity-H">

Cool animation from Mesai

2009-07-29T05:25:00.000-07:00

VIM code formatting

2009-07-13T14:45:00.000-07:00

I'm experimenting with Vim.
It's geeky!
:)

Sandeep Singhal made Vim more interesting to me with his post about formatting:
sandeepsinghal.blogspot.com

It's getting sick

2009-06-30T03:50:00.000-07:00

JavaFX Experiment

2009-02-18T16:29:00.000-08:00

Launch Sink A Ship

You can check out code on:
Google code

Open source company business model

2009-02-09T00:44:00.000-08:00

Interesting article about business model for open source company.
Hacking Business Models

Eclipse Singletone template

2009-01-26T05:23:00.000-08:00

Eclipse->Window->Preferences

Java->Editor->Templates->New..
Name:Singletone
Description:{whatever}
Pattern should look like:


// *** SIngletone impl
private static class InstanceHolder{
 private static ${enclosing_type} instance = new ${enclosing_type}();
}

private ${enclosing_type}() {}

public static ${enclosing_type} getInstance() {
   return InstanceHolder.instance;
}
// ***

Now every time you need quick singletone implementation you just type single and ctrl+space...

I looove eclipse

2009-01-13T06:51:00.000-08:00

We are bringing code review in our small team as an experiment. And I like it!
I liked it until I got "... and put brackets around every one statement if/else block..." in review of my code.
Thank you Oisin and thank you Eclipse!

Keep your code clean with Eclipse V3.3

Interesting code-review document

2008-11-24T03:31:00.000-08:00

Smartbear best practices

Syntax highlighter

2008-10-16T05:34:00.000-07:00

There was a time when I wanted to give up blogger because poor code formating options.

Google to the rescue:

http://code.google.com/p/syntaxhighlighter/

Dangerous SQL usage of "NOT IN"

2008-10-16T03:46:00.000-07:00

Here is example structure:


CREATE TABLE CUSTOMER
(
  ID                           INTEGER          NOT NULL,  
  FIRSTNAME                    VARCHAR          NOT NULL,
  LASTNAME                     VARCHAR          NOT NULL
);
CREATE TABLE CARD
(
  ID                          INTEGER           NOT NULL,
  CUSTOMERID                  INTEGER,
  SOMEDATA                    VARCHAR           DEFAULT 'ffff'
);
insert into card (id, customerid, somedata)
values (1, null, 'abcd');
insert into card (id, customerid, somedata)
values (2, null, 'efgh');
insert into card (id, customerid, somedata)
values (3, null, 'ijkl');
insert into customer (id, firstname, lastname)
values (1, 'John', 'Doe');
insert into customer (id, firstname, lastname)
values (2, 'Jane', 'Doe');
insert into customer (id, firstname, lastname)
values (3, 'Jim', 'Doe');
update card set customerid = 1 where id = 2;

SELECT
    MIN (customer.ID)
FROM customer
WHERE customer.ID NOT IN 
    (SELECT customerId FROM card WHERE customerId IS NOT NULL)

Last SELECT statement returns 2 which is ok but if you remove this part "WHERE customerId IS NOT NULL" all you get is NULL.
Database recognizes NULL value as "unknown".
It can't tell "I'm sure there IS NO customer.ID in that SELECT." because there are unknowns!!!
:)

Oracle analytic functions

2008-08-14T06:32:00.000-07:00

Simple example:
My firm with employees :)


-- Simple table
CREATE TABLE Emp
(
dept VARCHAR2(20) NOT NULL,
nick VARCHAR2(20) NOT NULL,
pay  NUMBER NOT NULL
);


-- All with different pays
INSERT INTO Emp
(dept, nick, pay)VALUES
('Admins' ,'Mike' ,5000 );
INSERT INTO Emp
(dept ,nick ,pay) VALUES
('Admins' ,'Michael' ,4000 );
INSERT INTO Emp
(dept ,nick ,pay) VALUES
('Admins' ,'Wellington' ,3000 );


-- First two with same pay checks
INSERT INTO Emp
(dept ,nick ,pay) VALUES
('Programers' ,'Bix' ,5000 );
INSERT INTO Emp
(dept ,nick ,pay) VALUES
('Programers' ,'Pierre' ,5000 );
INSERT INTO Emp
(dept ,nick ,pay) VALUES
('Programers' ,'Ivanhoehoe' ,3000 );
INSERT INTO Emp
(dept ,nick ,pay) VALUES
('Programers' ,'Boldrick' ,2000 );
INSERT INTO Emp
(dept ,nick ,pay) VALUES
('Programers' ,'Payson' ,1000 );


-- 3. and 4. with same checks
INSERT INTO Emp
(dept ,nick ,pay) VALUES
('CEOs' ,'Maush' ,50000);
INSERT INTO Emp
(dept ,nick ,pay) VALUES
('CEOs' ,'Pierre' ,4000 );
INSERT INTO Emp
(dept ,nick ,pay) VALUES
('CEOs' ,'Bob' ,3000 );
INSERT INTO Emp
(dept ,nick ,pay) VALUES
('CEOs' ,'Boldrick' ,3000 );
INSERT INTO Emp
(dept ,nick ,pay) VALUES
('CEOs' ,'Vlax' ,1000 );

row_number(), rank(), dense_rank()
Here is the difference in functions:


SELECT dept, nick, pay,
row_number() over (partition by dept ORDER BY pay desc) rnum,
rank() over (partition by dept ORDER BY pay desc) rnk,
dense_rank() over (partition by dept ORDER BY pay desc) densrnk
FROM Empdept nick pay RNUM RNK DENSRNK;

Admins	Mike	5,000	1	1	1
Admins	Michael	4,000	2	2	2
Admins	Wellington	3,000	3	3	3
CEOs	Maush	50,000	1	1	1
CEOs	Pierre	4,000	2	2	2
CEOs	Bob	3,000	3	3	3
CEOs	Boldrick	3,000	4	3	3
CEOs	Vlax	1,000	5	5	4
Programers	Bix	5,000	1	1	1
Programers	Pierre	5,000	2	1	1
Programers	Ivanhoe	3,000	3	3	2
Programers	Boldrick	2,000	4	4	3
Programers	Payson	1,000	5	5	4

Partition by
Watch what "partition by" can do:
If we need 3 most payed emps by department we surround our query with SELECT * FROM( ourQuery ) where rnum < 4


LEAD/LAG
-- LEAD/LAG
SELECT dept, nick, pay,
LEAD(pay, 1, 0) OVER (PARTITION BY dept ORDER BY pay DESC NULLS LAST) NEXT_LOWER_SAL,
LAG(pay, 1, 0) OVER (PARTITION BY dept ORDER BY pay DESC NULLS LAST) PREV_HIGHER_SAL
FROM Emp
ORDER BY dept, pay DESC;dept nick pay NEXT_LOWER_SAL PREV_HIGHER_SAL

Admins Mike 5,000 4,000 0
Admins Michael 4,000 3,000 5,000
Admins Wellington 3,000 0 4,000
CEOs Maush 50,000 4,000 0
CEOs Pierre 4,000 3,000 50,000
CEOs Bob 3,000 3,000 4,000
CEOs Boldrick 3,000 1,000 3,000
CEOs Vlax 1,000 0 3,000
Programers Bix 5,000 5,000 0
Programers Pierre 5,000 3,000 5,000
Programers Ivanhoe 3,000 2,000 5,000
Programers Boldrick 2,000 1,000 3,000
Programers Payson 1,000 0 2,000

FIRST_VALUE and LAST_VALUE
FIRST_VALUE and LAST_VALUE work on first and last record in table


-- FIRST_VALUE/LAST_VALUE
SELECT nick, dept, pay - FIRST_VALUE(pay)
OVER (PARTITION BY dept ORDER BY pay DESC) pay_GAP
FROM Emp
ORDER BY dept, pay_GAP DESCnick dept pay_GAP

Mike Admins 0
Michael Admins -1,000
Wellington Admins -2,000
Maush CEOs 0
Pierre CEOs -46,000
Bob CEOs -47,000
Boldrick CEOs -47,000
Vlax CEOs -49,000
Bix Programers 0
Pierre Programers 0
Ivanhoe Programers -2,000
Boldrick Programers -3,000
Payson Programers -4,000
KEEP
Dunno what this does.


--FIRST/LAST
SELECT dept,
nick,
pay,
MIN(pay) KEEP (DENSE_RANK FIRST ORDER BY pay) OVER (PARTITION BY dept) "Lowest",
MAX(pay) KEEP (DENSE_RANK LAST ORDER BY pay) OVER (PARTITION BY dept) "Highest"
FROM Emp
ORDER BY dept, pay;dept nick pay Lowest Highest

Admins Wellington 3,000 3,000 5,000
Admins Michael 4,000 3,000 5,000
Admins Mike 5,000 3,000 5,000
CEOs Vlax 1,000 1,000 50,000
CEOs Boldrick 3,000 1,000 50,000
CEOs Bob 3,000 1,000 50,000
CEOs Pierre 4,000 1,000 50,000
CEOs Maush 50,000 1,000 50,000
Programers Payson 1,000 1,000 5,000
Programers Boldrick 2,000 1,000 5,000
Programers Ivanhoe 3,000 1,000 5,000
Programers Pierre 5,000 1,000 5,000
Programers Bix 5,000 1,000 5,000

Have Fun!

Getting serious (Exporting PDF from Jasper)

2008-03-03T07:01:00.000-08:00

Ok, ok... Blogging is good for your health :)
My boss asked me today did I use JFlex and can I provide quick tutorial.
I used JFLex, JCUp... made some compiling efforts back then. But I can't remember a thing.
So, my first effort in getting serious :) will be my work in progress, using JasperReports and IReport.

IReport crash course
Ok, what is important.
Go to View->Fields. Field names are in my example "myObjectAttribute1" and "myObjectAttribute2". I'll use them later in Java for my data source method "getFieldValue(JRField jrField)". And thats all for simple report! :)
Put some static text, some pictures... and your text fields for "myObjectAttributes". Something like this:

Now save as "MyTemplateName.jrxml".
Compile.
Put it where your Java code can find it.
That's all.
What you need in your Java code
First you need a DataSource for your report. I needed swing table in my report so I'm getting my table model ArrayList and making MyDataSource:

 
public class CustomJasperDataSource implements JRDataSource {

MyObjectInMyTableClass chartEntry;

Iterator iterator;

ArrayList chartEntries;

public CustomJasperDataSource(ArrayList chartEntries) {
this.chartEntries = chartEntries;
iterator = chartEntries.iterator();
}

public Object getFieldValue(JRField jrField) throws JRException {
if (jrField.getName().equalsIgnoreCase("myObjectAttribute1")) {
 return chartEntry.getMyObjectAttribute1();
}
if (jrField.getName().equalsIgnoreCase("myObjectAttribute2")){
 return chartEntry.getMyObjectAttribute2();
}
...
return null;
}

public boolean next() throws JRException {
boolean hasNext = iterator.hasNext();
if (hasNext) {
 chartEntry = (MyObjectInMyTableClass) iterator.next();
}
return hasNext;
}

}

Invoking Jasper
This is called when you press some swing button:

 
protected void jButtonCreatePdfActionPerformed(ActionEvent e) {

 JasperPrint jp = generateReport(myArrayListOfData);
 JasperViewer jasperViewer = new JasperViewer(jp, false);
 jasperViewer.setVisible(true);

}

And this is how generateReport method looks like:

 
private JasperPrint generateReport(ArrayList data) {
    JasperPrint jasperPrint = null;
    String templateName = "MyTemplateName.jasper";
    try {
        jasperPrint = JasperFillManager.fillReport(templateName,
                new HashMap(), new CustomJasperDataSource(data));
    } catch (JRException e) {
                  doSOmeExcCatching();
    }
    return jasperPrint;
}

Some nice thoughts

2007-09-24T08:03:00.000-07:00

Martin Luther King:"History will record that the greatest tragedy of this period of social transition, was not the vitriolic words and actions of the bad people – but the appalling silence and indifference of the good people. Our generation will not only have to repent for the words and acts of the children of darkness, but also for the fears and apathy of the children of light."

Some nice thoughts

2007-09-12T02:37:00.000-07:00

http://devizen.com/blog/2007/09/11/ruin/
Blaise Pascal: “We never keep to the present. We … anticipate the future as if we found it too slow in coming and were trying to hurry it up, or we recall the past as if to stay its too rapid flight. We are so unwise that we wander about in times that do not belong to us and do not think of the only one that does; so vain that we dream of times that are not and blindly flee the only one that is… [We] think of how we are going to arrange things over which we have no control for a time we can never be sure of reaching… Thus we never actually live, but hope to live, and since we are always planning how to be happy, it is inevitable that we should never be so.”