B4J Question b4j and raspberry pi 2

[kalarius]

I try to run my program at raspberry pi 2 (the program run on windows 10 and b4j with java8)
but I got a lot of error messages at log field

even if I try to run this
ub AppStart (Form1 As Form, Args() As String)
MainForm = Form1
MainForm.SetFormStyle("UNIFIED")
'MainForm.RootPane.LoadLayout("Layout1") 'Load the layout file.
MainForm.Show
End Sub

java.lang.reflect.InvocationTargetException
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:483)
at sun.launcher.LauncherHelper$FXHelper.main(LauncherHelper.java:767)
Caused by: java.lang.NullPointerException
at com.sun.javafx.application.LauncherImpl.launchApplicationWithArgs(LauncherImpl.java:362)
.....
......
......
and more error

my configure path is
C:\Program Files\Java\jdk1.7.0_79\bin\javac.exe
and I have install the raspberry as earl describe at an other topic

what is going wrong ?

thank

 

[Erel]

UI apps are not supported. It is possible to install Java 8u6 on the raspberry pi and then it will work. But it will work slow and in full screen mode only.

 

[kalarius]

Installing Oracle JDK 8 on Raspberry Pi
Posted by Rahul Kar × 8:16 PM


This post will show how to download and set up Oracle JDK 8 on Raspberry Pi.

Visithttp://www.oracle.com/technetwork/java/javase/downloads/jdk8-downloads-2133151.html, click the download button of Java Platform (JDK) 8. Click to Accept License Agreement, download jdk-8-linux-arm-vfp-hflt.tar.gz for Linux ARM v6/v7 Hard Float ABI.


Log-in Raspberry Pi, enter the command to extract jdk-8-linux-arm-vfp-hflt.tar.gz to /opt directory.
$ sudo tar zxvf jdk-8-linux-arm-vfp-hflt.tar.gz -C /opt

Set default java and javac to the new installed jdk8.
$ sudo update-alternatives --install /usr/bin/javac javac /opt/jdk1.8.0/bin/javac 1
$ sudo update-alternatives --install /usr/bin/java java /opt/jdk1.8.0/bin/java 1

$ sudo update-alternatives --config javac
$ sudo update-alternatives --config java

After all, verify with the commands with -verion option.
$ java -version
$ javac -version


I install as describe above
now the compiler does not show any error but at the TV I do not see my application
The bridge refer that is connect
but how can I run the allplication on the raspberry?

 

[Erel]

Are you able to run a non-UI app?

 

[kalarius]

yes But I want to show a video on the screen

since now I have download and install the ver 8u65 but it has not include the javaFX I found a addin for java ver 8u40 and I can run a simple form But I can not run the program with MP.Initialize("mp",File.geturi("/home/pi","nba.mp4"))
it says that have problem with thae stack and thw VM try to fix it.
so now I try to find the java version 8u40 for the arms

do you know from where I can down load it because at the oracle archive at the 8u40 jdk does not have something for arms

 

[Erel]

You need to install Java 8u6 (8.06). This is the latest ARM version with JavaFX. However if I remember correctly it doesn't include MediaPlayer implementation.

 

[kalarius]

looking to solve the problem with javafx at the internet I found the arm6hf-sdk, anf following the instractions I manage to have run a simple program with a form but That i want is to paly a video on the screen Just one mp4 file The same again and again

With this program i read the follow message

Java HotSpot(TM) Client VM warning: You have loaded library /opt/jdk1.8.0_65/jre/lib/arm/libjfxmedia.so which might have disabled stack guard. The VM will try to fix the stack guard now.
It's highly recommended that you fix the library with 'execstack -c <libfile>', or link it with '-z noexecstack'.

this is the error message after I try to run the program the file libjfxmedia.so there is into the arm directory
but i do not know what the message wants to do

 

[Cableguy]

It seems to be related to the VM machine you're working on and to the RasPi... Have tried a "normal" windows machine?