By Sangyoon Oh
on the Palm (J2ME/MIDP/CLDC)
announced that it plans to ship a developer release of Java 2
Platform, Micro Edition technology and the Mobile Information Device
Profile (MIDP) for the Palm OS platform. If it is released, it will make
easy for developers using Java to create applications for the Palm
OS. This is not only
providing developer Java API for Palm OS, but also it allows Palm to use
Thousand of MIDP application, which is initially targeted at Mobile
PalmSource 2000 conference in Santa Clara, Ca, there are several J2ME
products for Palm. They are using Connected Limited Device Configuration
(CLDC) and Palm Overlay, which is evaluation version of CLDC API. If MIDP
for Palm is available as Sun announced, they can move on to CDLC plus
MIDP on Palm OS.
One of interesting product is a
wireless trading application from Swiss company, Ergon. It is based on Java and
operated on Palm platform. It uses IR as a communication method between Palm
and Mobile Phone. After it makes a wireless connection to Trading Server, SSL
3.0 gives secure transaction as equal as PC with wired-connection.
Demonstration of Egron¡¯s trading application-using Java
KVM be a perfect as its siblings, Waba is possible choice for Palm Java
Programmers. It is created by California Company Wabasoft and makes
Java-like coding for Micro OS (Palm OS / WinCE).
is a very strict subset of Java language for smaller device. Its VM need
just 34K in memory and additional 40K is for standard library.
important features of Java are removed to obtain micro-size VM. They are:
GUI: No AWT, No Swing.
Events: Very few event such as KeyEvent, No ActionListener and
Exception Handling: Lacks an Exception class.
Threads: No threads, No multithreading.
One other inconvenience is very
critical for network programmer like us. Waba package contains Socket class but
neither of exception class or ServerSocket class and the method in class is
very weak so you can only write and read Byte to Socket.
has better performance on Palm (Maybe, it left so many things out). Waba
classes are loaded almost 2 to 5 times faster than KVM class.
far, Waba won in reliability and performance. But as soon as Sun is
serious on Palm, as they announced, the power will shift to Sun¡¯s Java.
released WinCE 3.0 embedded operating system. It has many new features (http://www.microsoft.com/windows/embedded/ce/guide/features/whatsnew30.asp),
but among them, COM (limited features)/DCOM (Full support compatible with
Windows NT 4.0 SP5) support is eye-catching application service. Also it
has enhanced Microsoft Message Queuing Service (MSMQ), which is
independent message queuing service with Window 9x, NT and 2000
compatibility. The new Internet Explorer for WinCE 3.0 support XML,
128-bit SSL, HTML 4.0/DHTML and ActiveX controls.
OS 4.0 (Currently, 3.5) is planed to release this spring. But since Palm
OS 3.5 support 1, 2, 4, and 8-bit color and grayscale, there are not much
expected from this coming 4.0 version Palm OS. Palm OS is still market-dominant PDA OS and not only
Palm (3Com) is involved OS development and application. Rather, other
device manufactures such as IBM, Handspring, and Sony is also
participating in its development.
is a client for the Palm that provides remote access to VNC server
machine (PC/Mac/UNIX) over a normal TCP/IP network connection.
was originally written by Vladimir Minenko. He wrote version 1.1 for Palm
OS 1.0 to 3.1. Which were black and white display and the performance was
un-bearable. It was like not working after event was occurs.
Jan. 7th of 2001, PalmVNC version 1.40 has been released and
it solve the performance problems. Even the display for non-color device
is not very good, the performance improvement is remarkable. Initial
loading time for 1.10 is about a half minute and 1.40 version can be
initiated less than 6 seconds. Also, display refresh after event occurs
is several times faster than 1.10.
this test, PalmIIIx with Palm OS 3.3 and 9600bps Palm modem is used.
2 PalmVNC 1.40
Wireless Service provider, such as OmniSky, connects many Palm devise to
network. But Wireless LAN is more and more popular after they have power
on price and performance. Definitely, the price matters are including
installation and maintenance issues. Based on IEEE 802.11b protocol standard,
we can get 11Mbps on it. And IEEE 802.11a will be 54Mbps. à
Mature enough to use
- Bluetooth: In fact, the future of Bluetooth
was vague. After the specification has been released, it is rare (Not
much product on the market), buggy (More complete version 1.1 will not
release until June) and it is above the affordable price range.
Currently, early products of 1.0 are reported that it has power consuming
and interoperability problems. UK based CRS is trying to push down
Bluetooth chip price to $5 from current $15. If it will be by this
summer, that make a big effect on wireless connection market with new
released version, since Bluetooth will make a better effect on
Collaboration. It is not only make a connection to LAN (like wireless
LAN); rather it will make a connection with any of Bluetooth device. à
Premature to use.
is a simple implementation of ¡°Control Java3D object from PDA with Waba
application¡±. Java3D object communicates with Waba application on PDA
over TCP/IP socket over Wireless LAN.
- .ppt: Java3D Controlling over PDA-Server
Pic 4. User
Interface on PDA