SUN: PC+ Monitor + Color Printer Under $300

After huge China deal, SUN seems to be on roll. AOL started started selling PC (With Monitor, Color Printer, Star Office rebranded as AOL Office) for $299.
This could be huge. The only gotcha is that you have to commit to use AOL for a year($23.90 per Month). If this offer becomes successful you find more and more home users using Star Office. I am sure J2SE1.4 is preinstalled on these machines (Though not mentioned anywhere).
Find the offer from AOL here:

An interview with Java Desktop System team is published at OS News.

J2ME: MIDP2.0 phone from Motorola

Motorola i730 is available in us markets. Key features:
J2ME Support : MIDP 2.0 (JSR 118),Mobile Media(JSR 135), WMA (JSR 120)
OEM Support: Motorola LWT, Look And Feel, Polyphonic MIDI, WAV, AU, Vibrator, Lighting, Motion JPEG, Still image capture, Location API, Phonebook, Datebook, External display, Call Receive and Initiation, Recent calls, File I/O, Serial port, Crypto, Digital Camer, Java Menu MIDlet icon, RF enabling, Alpha blending, Secure file connection, Voicenote, 3D
Heap Size: 1.15 MB
Midlet Storage: >2MB (installed MIDlet space), >2MB (file storage), Recommended Maximum jar file size is 500KB. Now serious business applications and Games are possible on i730.
Max Sockets: TCP: 16,HTTP: 8,UDP: 24 (21 according to developer guide and 24 according to Device specs).
65K Color Display: Vibrant display with enhanced clarity allows you to customize your screen with downloadable wallpapers, adjustable color palettes, and choice of three font sizes.
Concurrency: Supports execution of upto 3 MIDlets at the same time. (Ofcourse only one MIDlet can be in foreground).

Another cool innovative feature is Airplane Mode where you can turn off network connection and use programs, games, voice record, and datebook. Phone will display “Airplane Mode” while in use and display “Service Restricted Airplane Mode On”. The nice thing about i88S and i730 from Motorola is that you can query your location from your phone(using J2ME) without paying a single cent.

Compared to this my Motorola i88s looks so dumb and ugly. I wish I can exchange my phone :-)

M$: Another entry to hall of shame

Image is self explanatory:

J2SE: 10 References for 1.4.X GC

Sun has several docs for 1.4.x GC settings. Here are 10 of them:
1. Performance FAQ.
2. Java HotSpot VM Options.
3. Tuning Garbage Collection with 1.4.2.
4. Threading.
5. Big Heaps and Intimate Shared Memory.
6. Performance White Paper(1.4.2).
7. HotSpot FAQ(1.4.2).
8. Improving Java Application Performance and Scalability by Reducing Garbage Collection Times and Sizing Memory Using JDK 1.4.1.
9. Java HotSpot Virtual Machine.
10. Turbo-charging the Java HotSpot Virtual Machine, v1.4.x to Improve the Performance and Scalability of Application Servers.

Directories are Java source file package names

After reading this blog by Gregg Wonderly and some of the comments posted at the blog I decided to write this blog entry.
For a long time I used to think directories are not Java source file package names because Chapter 7 of Java language specification said so. Also many a times(For any product that you work on for long time) maintaining directories as Java source file package names is a pain. Imagine you are developing a product called javamagic. You are working for a oraganization which has several suborganizations and with several products for each sub organization. If your java source files must be in a directory tree mirroring the package name, your source directory would typically look something like this:

Having this structure is pain and sounds dumb because you know com/javaswamy/jone/javamagic is always constant and there is absolutely no need to maintian this filesystem hierarchy as you know what you are working on. If possible a simple hierarchy like this would be what everyone likes to have:

This is easy to navigate and presents developer view of the code.

Now lets get back to reality. Though Java Language Specification doesn't impose the restiction of Directories are Java source file package names, JavaDoc does. JavaDoc tool faq states "If your classes do not all belong to the unnamed package, you must put them in directories named after the packages.". So if you need to generate javadocs for your project and use JavaDoc tool to generate the documentation, Directories are Java source file package names.

Like many other java programmers, I would love to see JavaDoc team solve these problems that exist since JDK1.1 days:
1. Directories are Java source file package names.
2. Deprecation warning is suppressed if the compilation unit containing the deprecation is being compiled at the same time as the compilation unit using the deprecated class or member.

Office: OpenOffice.org 1.1 released

OpenOffice.org announced first major update to OpenOffice. 1.1 is now final and English version is available for download on Windows, Solaris and Linux. I have been using 1.0.x versions and 1.1 RC's for a while. With every update OpenOffice is getting better and better and better compatability with M$ Office. OpenOffice is now the only office suite on my home machine.
The two new major features for me in 1.1 update are export to PDF format from OpenOffice.org Writer and export to Macromedia Flash format (.swf) from OpenOffice.org Impress. Support for export to PDF got better with every update.
Checkout my blog archive for the month 2003_09 exported to PDF from Writer:Kumar Mettu's Blog.pdf. The only data lost from saved html file is Hyperlinks.
Here is a simple presentation exported to Macromedia Flash format (.swf):


Check out OpenOffice.org XML Essentials book online.

J2ME: Get Weather Forecasts Free

Weather on Demand is one of the most common applications of SMS. Few of weather service examples are:

1. Weather alerts from Verizon .
2. Weather Network and TELUS Mobility's On Demand Weather service and
3. Weather.com's Radar on Mobile Phones.
With a simple MIDlet you can get Weather forcasts free on your phone. US government provides free weather forecasts here. Note that the weather forecasts are not as high quality as commercial services. The simple MIDlet here displays weather at SF(modify the URL to point to your city):

001 import java.io.IOException; 002 import java.io.InputStream; 003  004 import javax.microedition.io.Connector; 005 import javax.microedition.io.StreamConnection; 006 import javax.microedition.lcdui.Command; 007 import javax.microedition.lcdui.CommandListener; 008 import javax.microedition.lcdui.Display; 009 import javax.microedition.lcdui.Displayable; 010 import javax.microedition.lcdui.Form; 011 import javax.microedition.midlet.MIDlet; 012  013  014 /** 015  * MIDlet to display weather forecast for SF. 016  * 017  * @author Kumar Mettu 018  * @version 1.0 019  * 020  */ 021 public class Weather extends MIDlet implements CommandListener { 022  023     private Display display; 024     //Exit command. 025     private Command  exitCommand = new Command( "Exit", Command.SCREEN, 1 ); 026     //SF Weather URL. 027     private static final String SF_URL = 028         "http://weather.noaa.gov/pub/data/forecasts/city/ca/san_francisco.txt"; 029  030     /** 031      * Weather MIDlet constructor. 032      */ 033     public Weather() { 034        display = Display.getDisplay(this); 035     } 036  037     /** 038      * This will be invoked when we start the MIDlet. 039      * Display the downloaded data. If an error occurs while downloading 040      * the data display the error to user. 041      * 042      */ 043     public void startApp() { 044         try { 045             getViaStreamConnection(); 046         } catch (IOException e) { 047             Form forecast = new Form("Error Downloading"); 048             forecast.append(e.getMessage()); 049             forecast.addCommand( exitCommand ); 050             forecast.setCommandListener( this ); 051             display.setCurrent(forecast);        052        } 053     } 054  055     /** 056      * Pause, discontinue .... 057      */ 058     public void pauseApp() { 059  060     } 061  062     /** 063      * Destroy. Cleanup everything. 064      */ 065     public void destroyApp(boolean unconditional) { 066     } 067  068     /** 069      * Download the weather and display it. 070      * 071      * @throws IOException when IO Error occurs while downloading 072      *  data from URL. 073      */ 074     private void getViaStreamConnection() throws IOException { 075         StreamConnection sc = null; 076         InputStream in = null; 077         StringBuffer b = new StringBuffer(); 078  079         try { 080           sc = (StreamConnection)Connector.open(SF_URL); 081           in = sc.openInputStream(); 082           int ch; 083           while ((ch = in.read()) != -1) { 084              b.append((char) ch); 085           } 086  087         } finally { 088            if (in != null) { 089               in.close(); 090            } 091            if (sc != null) { 092               sc.close(); 093            } 094         } 095  096         Form forecast = new Form("Weather at SF"); 097         forecast.append(b.toString()); 098         forecast.addCommand( exitCommand ); 099         forecast.setCommandListener( this ); 100         display.setCurrent(forecast); 101     } 102  103     /** 104      * Indicates that a command event has occurred on Displayable d. 105      * @param c - a Command object identifying the command. 106      * @param d - the Displayable on which this event has occurred. 107      */ 108     public void commandAction( Command c, Displayable d ){ 109         if (c == exitCommand){ 110             exit(); 111         } 112     } 113  114   /** 115    * Distroy app when exit button is used. 116    */ 117     private void exit(){ 118         destroyApp(true); 119         notifyDestroyed(); 120     }     121  122 }

You can download Weather.jar and Weather.jad directly. Tested on my i88s. Here is the screen snapshot of Motorola i88s simulator:



This can be further extended to support features like:
1. Select the city where you want weather forcast(using kxml)
2. If your phone supports GPS( like my Motorola i88s), you can display weather forecasts for your current location.