• The Java IrDA API is another Open Source project from HP, again built thanks to contributions from the community. The API was initially written by A.Venkataramani thanks to Hewlett Packard sponsoring his work.
• The API is very similar to java.net.Socket API and has been implemented using the Linux-IrDA stack (version included in kernel 2.4.0 and above).
• The API is also interoperable with Microsoft Windows 98, Windows 2000 and Windows CE IrSock, and with Linux-IrDA IrSock. Hence, the peer for this API could be an application running on a WinCE device such as HP Jornada 540/720/820 or on a Windows/Linux workstation.
• The specification of the API is not Linux-specific, so it would be possible to offer the same API on a variety of platforms, and have Java-IrDA applications run anywhere. However, the present package is implemented on top of Linux-IrDA IrSock and uses a few Linux-specific features, so the low level part of the package would need some slight changes for other platforms.
• Both connection oriented streams (IrSocket and IrServerSocket) and connectionless Ultra (UltraSocket and UltraPacket) interfaces are available. Sequenced packets and datagrams sockets are not implemented, because rarely used, but would be easy to add if needed.
• The API has been tested out on Linux RedHat 6.1 and GNU/Linux Debian 2.2 running Blackdown JDK 1.2 and 1.2.2, both using a serial to Infrared dongle.
• This API is defined directly on top of the Linux kernel, but of course you will need the Linux-IrDA stack up and running.

This API is distributed under the terms of the GNU Lesser General Public License.

Download

Java_IrSockets-1.1.tar.gz (37 kB) : everything is included in this archive.

A sample Java code using the API look like this.

Documentation

hp.infrared package (also provided in the .tar.gz file)

Installation

See the INSTALL and README files included in the .tar.gz file.

The Java-IrDA API require the IrDA stack in kernel 2.4.0. I've got also basic installation instructions for this version of the Linux-IrDA stack.

Communication with a Palm

The Palm mostly uses a protocol called Obex to exchange various objects (business cards, appointements, ...). Obex is a standard IrDA protocol implemented on top of the IrDA sockets, and that is more or less a compressed version of HTTP.

There exist some implementation of Obex for Linux and Win32 written in C, the most popular beeing OpenObex. But, of course, you want to do your coding in Java. We have looked in doing a JNI wrapper around the OpenObex library, but I must admit that the OpenObex API is not appropriate for this.

The other solution is to do an implementation of Obex in Java, written on top of the Java-IrDA API. In fact, the JRed project already contains a cut down version of Obex written in Java, and it should be an easy task to port it over our API. Another project that may have an Obex implementation in Java in the future is Jir.

Contact

If you find any bugs, have suggestions, please contact A.Venkataramani (avramani@india.hp.com) or Jean Tourrilhes (jt@hpl.hp.com).

IrNET and e-Squirt

e-Squirt is one of the main protocol used in Cooltown. One of the main use of the Java-IrDA API was to offer a way to use e-Squirt in Java applications. I also did some sample e-Squirt implementations for Linux in C.

You might also be interested in IrNET, a module allowing you to transport TCP/IP over an IrDA socket. This would allow you to use regular TCP/IP sockets in Java over IrDA...

This package is an offshoot of the Cooltown Appliance Computing project of Hewlett Packard Laboratories.