your libary does not work

[pcmadn...@gmail.com]

clean install used you example build 

error 

pi@raspberrypi:/opt/pi4j/examples $ sudo java GpioOutputExample 

Error: A JNI error has occurred, please check your installation and try again

Exception in thread "main" java.lang.NoClassDefFoundError: com/pi4j/platform/PlatformAlreadyAssignedException

at java.lang.Class.getDeclaredMethods0(Native Method)

at java.lang.Class.privateGetDeclaredMethods(Class.java:2701)

at java.lang.Class.privateGetMethodRecursive(Class.java:3048)

at java.lang.Class.getMethod0(Class.java:3018)

at java.lang.Class.getMethod(Class.java:1784)

at sun.launcher.LauncherHelper.validateMainClass(LauncherHelper.java:544)

at sun.launcher.LauncherHelper.checkAndLoadMain(LauncherHelper.java:526)

Caused by: java.lang.ClassNotFoundException: com.pi4j.platform.PlatformAlreadyAssignedException

at java.net.URLClassLoader.findClass(URLClassLoader.java:381)

at java.lang.ClassLoader.loadClass(ClassLoader.java:424)

at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331)

at java.lang.ClassLoader.loadClass(ClassLoader.java:357)

... 7 more

[Harald Sattmann]

Hi

Are you SUDO

[pcmadn...@gmail.com]

indeed see my dump from console

[Raffy Ibasco]

First of all, it DOES work. 

Secondly, Is this your first time using Java?  The problem is pretty obvious just by looking at the stack trace... You are trying to run the program without even specifying the classpath entries. I suggest  you run it with the built-in utility script instead. 

# pi4j -r GpioOutputExample

[pcmadn...@gmail.com]

thats what i did and i been using java for many years

[Raffy Ibasco]

From the console dump you posted above, it showed that you did a

sudo java GpioOutputExample

 instead of 

pi4j -r <example>.java

[pcmadn...@gmail.com]

is there a way and can use java command nativly with your libary

[Robert Savage]

Sure, take a loot at this example

http://pi4j.com/example/control.html

At the bottom of the page there is a section on EXECUTING the sample code using the java command line. 

Note that the java command line must include the classpath to find the Pi4J libraries on your system.

javac -classpath .:classes:/opt/pi4j/lib/'*' -d . ControlGpioExample.java

Thanks, Robert

[pcmadn...@gmail.com]

pi@raspberrypi:/opt/pi4j/examples $ sudo pi4j GpioOutputExample + java -classpath '.:classes:*:classes:/opt/pi4j/lib/*' GpioOutputExample

************************************************************

************************************************************

                  <-- The Pi4J Project -->                  

                     GPIO Output Example                    

************************************************************

************************************************************

------------------------------

|    PRESS CTRL-C TO EXIT    |

------------------------------

Unable to determine hardware version. I see: Hardware : BCM2835

,

 - expecting BCM2708 or BCM2709.

If this is a genuine Raspberry Pi then please report this

to proj...@drogon.net. If this is not a Raspberry Pi then you

are on your own as wiringPi is designed to support the

Raspberry Pi ONLY.

[Robert Savage]

Which version of Pi4J do you have installed?

pi4j --version

You may need to upgrade to the latest 1.2-SNAPSHOT version.  

http://pi4j.com/download.html

On Wednesday, August 2, 2017 at 6:15:01 PM UTC-4, pcmadn...@gmail.com wrote:

pi@raspberrypi:/opt/pi4j/examples $ sudo pi4j GpioOutputExample + java -classpath '.:classes:*:classes:/opt/pi4j/lib/*' GpioOutputExample

************************************************************

************************************************************

                  <-- The Pi4J Project -->                  

                     GPIO Output Example                    

************************************************************

************************************************************

------------------------------

|    PRESS CTRL-C TO EXIT    |

------------------------------

Unable to determine hardware version. I see: Hardware : BCM2835

,

 - expecting BCM2708 or BCM2709.

If this is a genuine Raspberry Pi then please report this

to .... If this is not a Raspberry Pi then you

[Andrew Chandler]

The latest kernel update changed how the CPU identifies itself. Wiring pi which pi4j relies on is hard coded to only support real raspberry pi so it checks that identifier. They have fixed that check I believe but it does require the update.

[pcmadn...@gmail.com]

this was a fresh install  a few days ago and also updates as well to get this working 

Wiring pi works fine its your libary that produces the error 

[Robert Savage]

@pcmadn...@gmail.com,

Please see this thread:

https://github.com/Pi4J/pi4j/issues/349

You either need to use 1.2-SNAPSHOT builds or use the dynamic linking option.