Using RXTX In NetBeans

From Rxtx

Installation in a project

Under Netbeans 5.5 on Windows, I needed to right-click Libraries under Projects on the left hand side of the screen, and select "Add JAR/Folder", picking the RXTXcomm.jar file.

Only then did my

import gnu.io.*; 

become a valid command.

Also, I got a run-time error where it failed to load the rxtxSerial.DLL library because it couldn't find it. I needed to right-click the project name, select properties, select Run under categories, and add a VM Options: entry of

-Djava.library.path="C:\where-ever-you-stuck-rxtxSerial.DLL-file;%PATH%

Example:

-Djava.library.path="C:\rxtx-2.1-7-bins-r2\Windows\i368-mingw32\;%PATH%"

While I'm sure there is more than one way of adding the directory to your path, this worked for me. Note I did the default NetBeans 5.5/JDK 1.6.0 isntall accepting all the default options(ie clicking next until I got to finish), so I haven't modified my java paths or anything.

Alternatively you can copy the *.dll into C:\Windows\System32\, Java will find it there automatically.

Note that you cannot use the 32bit DLL when running a 64bit JRE:

You will get an error similar to:

Can't load IA 32-bit .dll on a AMD 64-bit platform thrown while loading gnu.io.RXTXCommDriver

To solve this simply install the 32bit JDK and add a new Platform in Netbeans under Tools->Java Platforms->Add Platform and change the project settings to use the newly created platform. make sure you type "import gnu.io.*"

Installing under JDK

If you have followed the installation method of copying files into "Java\jreXXX\lib\ext" and "Java\jreXXX\bin" and have the same problem descibed above, you should note that for using Netbeans you must have installed JDK first, wich in turn may have installed its own JRE, on that case to fix said problem you should simply copy the .jar and the .dlls to "Java\jdkXXX\jre\lib\ext" and "Java\jdkXXX\jre\bin". It works like a charm.