Substance of Code

Thanks Atlassian

Tommi Laukkanen — Fri, 18 Jul 2008 21:22:29 +0000

It was a nice suprise to find Atlassian’s Codegeist T-shirt from my mailbox the other day. This year I was only able to code a small plugin for JIRA called NetBeans JIRA Plugin. I got the idea for this plugin as I was reading a book, Rich Client Programming, which has a great value when you are programming rich desktop apps or plugins for NetBeans platform.

Atlassian Codegeist T-Shirt

The plugin uses JIRA’s Web Service API to search, view and edit issues straight from the IDE. This is especially handy when you are writing a code to a specific issue and want to check some details or log work done for the issue.

The Atlassian Codegeist is a competition where everyone can write plugins for Atlassian products, such as JIRA, Bamboo, Confluence, FishEye, Crucible etc. I use those tools daily at work and I can truly say that they really improve the daily development process signifigantly.

ShareThis

Sending files to mobile phone using Bluetooth and OBEX

Tommi Laukkanen — Fri, 20 Jun 2008 11:43:46 +0000

My previous posting “Using Bluetooth stack in desktop application” was quite a success if measured by the number of comments. It seems that there aren’t many tutorials or articles about the Desktop usage of Bluetooth.

Here is a next chapter in the same category: using Bluetooth to send files from a computer to a mobile phone.

Read on if you are interested…

I wrote this small application so that I could send files (images) to my phone using the Bluetooth.

Creating a new application

I used NetBeans IDE to create this application. First I created a new Java application project. I created a following files for the app:

ApplicationContext.java - Contains list of devices near-by
ApplicationFrame.java - Actual UI, extends JFrame
BluetoothBrowser.java - Helper class to browse near-by devices
ListItem.java - DAO class used by ApplicationFrame
Main.java - Application entry point
SendFileTask.java - The OBEX magic for sending a file

I designed the UI with NetBeans IDE’s Matisse editor, which allows developer to design desktop user interfaces very easily.

Next I added code for searching devices when user presses the Refresh button. This was already discussed in the previous article. Also simple coding was done for browsing the file when Browse button gets clicked.

Next step was to add the actual business logic for sending the file to a selected Bluetooth device when Upload file to device button is clicked.

Code for upload button action performed

// Get selected item from list
ListItem selectedItem =
(ListItem) deviceList.getSelectedValue();
RemoteDevice device = selectedItem.getDevice();
// Build URL for the bluetooth device, note the port 9
String url =
"btgoep://" + device.getBluetoothAddress() + ":9";
// Get file as bytes
FileInputStream stream =
new FileInputStream(fileTextField.getText());
File f = new File(fileTextField.getText());
int size = (int) f.length();
byte[] file = new byte[size];
stream.read(file);
// Filename
String filename = f.getName();
// Trigger the task in a different thread
// so it won’t block the UI
SendFileTask task =
new SendFileTask(url, file, filename);
Thread thread = new Thread(task);
task.run();

Next step was to write the code for sending a file using the OBEX protocol.

Code for send file task

/*
* To change this template, choose Tools | Templates
* and open the template in the editor.
*/
package bluetoothfileexchange;
import java.io.OutputStream;
import javax.microedition.io.Connection;
import javax.microedition.io.Connector;
import javax.obex.ClientSession;
import javax.obex.HeaderSet;
import javax.obex.Operation;
/**
*
* @author Tommi Laukkanen (tlaukkanen at gmail dot com)
*/
public class SendFileTask implements Runnable {
private String btConnectionURL;
private byte[] file;
private String filename;
public SendFileTask(
String url, byte[] file, String filename) {
this.btConnectionURL = url;
this.file = file;
this.filename = filename;
}
public void run() {
try {
Connection connection =
Connector.open( btConnectionURL );
// connection obtained
// now, let’s create a session
// and a headerset objects
ClientSession cs =
(ClientSession) connection;
HeaderSet hs = cs.createHeaderSet();
// now let’s send the connect header
cs.connect(hs);
hs.setHeader(HeaderSet.NAME, filename);
// content-type could be
// checked from a filename
hs.setHeader(HeaderSet.TYPE, "image/jpeg");
hs.setHeader(
HeaderSet.LENGTH,
new Long(file.length));
Operation putOperation = cs.put(hs);
OutputStream outputStream =
putOperation.openOutputStream();
outputStream.write(file);
// file push complete
outputStream.close();
putOperation.close();
cs.disconnect(null);
connection.close();
} catch (Exception e) {
e.printStackTrace();
}
}
}

That was it. Now when the application is run, user can send a selected file to a selected Bluetooth device. I get a normal “Message received” notification on my mobile phone, Nokia N80, when I send a new image file to the phone.

You can download the whole project along with source codes from here.

ShareThis

Mobile Trail Explorer v1.10

Tommi Laukkanen — Tue, 06 May 2008 19:42:37 +0000

Lots of coding have been done for the next version of Mobile Trail Explorer. I’m happy to announce the release of version 1.10. This release contains many fixes such as loading/saving of trails. Previous version wasn’t necessarily able to load saved trails because of corrupted data.

Another nice feature is the ability to import both trails and waypoints from KML files so now you can create trail in Google Earth and import it to Mobile Trail Explorer where you can display it as a ghost trail that you can follow.

There is also a new feature for allowing you to post your location to web and create a web service that records your trails. User guide contains a bit more information about this. Location can be posted in the specified URL with query parameters like this:

…/record.php?lon=@LON@&lat=@LAT@&alt=@ALT@

It is very recommended to uninstall the previous version and it’s data before installing this release.

Here are release notes for the v1.10:

Support varying screen sizes like rotating screen on N95
Improved startup time
Support for uploading position to web server
Scrolling (up/down) on the information screen
Fixed the saving/loading of trails using RMS
Import trails from KML files
Import waypoints from KML files
Fixed waypoint editing when handling quickly added or imported waypoints

??????

Lots of great feature ideas have been shared in the Google Group discussions so join the conversations if you have some feature needs in your mind.

You can download the binaries (JAR and JAD) from Mobile Trail Explorer page???????? and source code can be downloaded from Google Code project page.

Go ahead and start recording your trails!

ShareThis

Analog clock service for web apps

Tommi Laukkanen — Sat, 12 Apr 2008 21:13:10 +0000

I’m nowadays working in an international company which has offices in multiple countries. I was looking for a way to get our Confluence, Enterprise Wiki, to display current time in all of our offices in one page. I didn’t find any simple solutions as lots of services just provided me a chunk of HTML that I could add to my page to create a dynamic clock but wiki syntax doesn’t really let me do that.

I’m a great fan of Google Charts API. Developers at Google have developed a really nice URL based API for the charting purposes. This was inspiration for me when I created Clock Service API for my own needs.

Clock Service is a simple servlet implementation that generates an image with the specified parameters. API can be used to define image size (s=100), timezone (tz=zone), title (t=Helsinki) and 12h/24h format (f=24). With this I can use the following URLs to produce three different clock images for three different timezones.

/clockservice/clock?tz=America/New_York&s=150&t=Atlanta&f=12
/clockservice/clock?tz=Europe/Helsinki&s=150&t=Helsinki&f=12
/clockservice/clock?tz=Australia/Sydney&s=150&t=Sydney&f=12

If you use those URLs in IMG tags then the result would look like this:

The images above aren’t created dynamically as I don’t have any public servlet container available.

The code behind the service is really quite simple. There are only two classes ClockServlet and Clock. Servlet implementation is only used for parsing the parameters from the request and writing the bytes from Clock.getImageData(..) to the web response.

Timezones are handled using the Java’s Calendar and TimeZone classes like this:

TimeZone tz = TimeZone.getTimeZone("Europe/Helsinki");
Calendar cal = Calendar.getInstance(tz);
int hour = cal.get(Calendar.HOUR);
int minute = cal.get(Calendar.MINUTE);

You can find the source code and compiled WAR package from the application page, here. Application is distributed under the Apache License v2.0.

ShareThis

Test driving NetBeans IDE 6.1 Beta

Tommi Laukkanen — Tue, 08 Apr 2008 20:49:52 +0000

I’ve been using NetBeans IDE for quite a few years now. It has improved very nicely over the years and it have became a top player in the IDE field. If you are a Eclipse or IDEA developer I’d suggest you to at least try it out as it is not the same as it was year before.

I’m eagerly waiting for the actual release as it is packed with useful features that will truly improve the development flow. Here are some of the features what I’m waiting for the most:

JavaScript support with semantic highlighting, code completion, type analysis, quick fixes, semantic checks and refactoring
Spring framework support with features such as configuration file support, code completion and hyperlinks to speed navigation
New MySQL support in the Database Explorer to make it easier to create, launch and view MySQL databases
+lots of other features

See some of the highlights in action after the jump.

JavaScript Support

I’ve been doing lots of web development lately so the JavaScript support is definitely coming handy. I especially like the code completion that feels to work very well. I listened Java Posse podcast few days ago and there Tor Norbye explained that the editor is indeed using semantic code completion so it will do a better job then most of the other JavaScript editors that only rely on the external index files in code completion.

Code completion also displays method documentation if available as seen here:

MySQL support

It was clear that NetBeans would have a better MySQL support since the Sun Microsystems bought MySQL. It is now nicely integrated into the database management section in Services view:

Plus there are probably hundreds of minor tweaks and fixes that will make the IDE even better. You can read the full beta information page to get full details. So to borrow some words from the movie Full Metal Jacket:

This is my IDE, there are many like it, but this one is mine! :)

ShareThis

Mobile Trail Explorer v1.9

Tommi Laukkanen — Tue, 01 Apr 2008 20:00:38 +0000

I’m proud to announce the release of Mobile Trail Explorer v1.9. Big thanks for all contributors and team members. This version should fix some of the issues with the Sony Ericsson phones and add bunch of great features such as:

Trail is now projected using the mercator projection
Both trail and map are now zoomed with same keys (1 and 3)
File browser for importing trails and selecting export path
Logger can now write to the filesystem
Signal strength SNR key to Sky View and updated help screen
Change screen on space key as well as 0 key
Export and import waypoints

One of the most wanted feature is the support for the internal GPS devices such as Nokia N95 and E90. This is now implemented in this version and it can be activated from the menu:

Settings > Development Menu > Use JSR179 (if available)

It would be great if N95, E90 and other JSR-179 device owners could test out this feature and report how it is working for them. This is something that will get me buying N95 (or N96) if we get it working correctly.

Go ahead and download the latest binaries from here or download the whole source from here. Don’t forget to send your feedback either to this blog post or to the Google Group of Mobile Trail Explorer.

ShareThis

Twittering with Twim v1.0

Tommi Laukkanen — Sun, 02 Mar 2008 21:09:52 +0000

I have made a small improvements to my mobile Twitter client that is called Twim. I contacted Twitter engineers and they helped me so that status updates will now have a correct source in style “… from Twim” as seen on my Twitter page. You can also now check the transferred data amount from the about screen. Here is a photo of Twim running on my Nokia N80. As you can see, it also now displays the status time (e.g. 2 hours ago).

So please upgrade your Twim to the latest version by downloading it from here. If you are a software developer you might be interested in looking at the source code that is available here with the Apache License 2.0.

Please send me any feature suggestions, bug reports and Twitter feeds that I should be checking out :) Happy Twittering!

ShareThis

Charting with JFreeChart

Tommi Laukkanen — Sat, 26 Jan 2008 21:53:29 +0000

I’ve been coding dashboard applications lately with Java SE. I have used JFreeChart library to generate all pie, line and bar charts. The library is awesome and is also Open Source. It would be very nice to see similar projects in the .NET world.

It was very easy to create first charts with JFreeChart mostly because it is so commonly used so there are many resources available in the Internet including tutorials and tips&tricks.

Here is a small sample how to create a simple pie chart and use it in your Swing application:

// First create dataset
DefaultPieDataset dataset = new DefaultPieDataset();
dataset.setValue("Finland", 5300367);
dataset.setValue("Sweden", 9107649);
dataset.setValue("Norway", 4606363);
dataset.setValue("Denmark", 5427459);
dataset.setValue("Iceland", 309699);
// Create chart using the ChartFactory
JFreeChart chart = ChartFactory.createPieChart(
"the Nordic countries", // Title
dataset, // Dataset
false, // Don’t show legend
false,
false);

The following code adjusts chart appearance and section colors. This is not mandatory but shows how easily you can customize the visual parts of the chart.

// Adjust appearance (optional)
chart.getTitle().setPaint(Color.LIGHT_GRAY);
chart.setAntiAlias(true);
PiePlot plot = (PiePlot)chart.getPlot();
plot.setShadowPaint(Color.DARK_GRAY);
plot.setBackgroundPaint(
new GradientPaint(0,0,Color.DARK_GRAY,0,100,Color.GRAY) );
plot.setLabelBackgroundPaint(Color.GRAY);
plot.setLabelLinkPaint(Color.LIGHT_GRAY);
plot.setLabelOutlinePaint(Color.LIGHT_GRAY);
plot.setLabelShadowPaint(Color.DARK_GRAY);
// Adjust section colors (optional)
Color[] colors = {
new Color(0xB0CC99),
new Color(0×677E52),
new Color(0xB7CA79),
new Color(0xF6E8B1),
new Color(0×89725B)
};
for(int i=0; igetItemCount(); i++) {
Color sectionColor = colors[i%colors.length];
plot.setSectionPaint(i, sectionColor);
}

That is all you have to do to create a chart object. Then if you wish to display this chart for example in your Swing application you’ll need to do the following:

ChartPanel chartPanel = new ChartPanel( chart );
yourPanel.add( chartPanel );

And this is the result:

ShareThis

Fix for Sony Ericsson phones (MTE Beta)

Tommi Laukkanen — Tue, 08 Jan 2008 21:10:11 +0000

Lots of Mobile Trail Explorer users have complained that application doesn’t work with Sony Ericcson phones. Latest version (1.8) doesn’t even seem to start. Phone only displays “Operation Failed” error message.

Fortunately there are some active people in the community as one of the users discovered the source for the problem. He wrote the solution to the Google Code’s project site describing that the use of Samsung and Siemens specific APIs for the backlight feature was causing the trouble. When references were removed from the code base the application worked without problems.

import com.samsung.util.LCDLight; import com.siemens.mp.game.Light; ...

Shortly after this I made the same changes to the code and I uploaded the fixed version for people to try out and I have already received multiple positive feedbacks from this change. Please try it out yourself and report back if the problems with the v1.8 are gone. Note: Unfortunately OutOfMemory exceptions are still there but hopefully we are also able to fix those in the future releases.

Download the beta v1.9 build here.

ShareThis

NetBeans Goodies

Tommi Laukkanen — Thu, 20 Dec 2007 22:04:57 +0000

I thought it was already Christmas as I just received a package from Sun Microsystems full of NetBeans goodies. I won these from the NetBeans.TV competition. Package included nice T-shirt, Rich Client Programming book, NetBeans pen, 1Gb memory stick and stress ball (or cube actually).

I have used NetBeans IDE 6.0 from the early daily builds and participated into NetCAT 6.0 program which was very nice experience. Now I’m using the latest release version of the NetBeans IDE and I’m loving every minute of it! NetBeans team have done excellent job! Best IDE just got better :)

Go ahead and download the latest release if you haven’t tried it out already.

ShareThis