This document provides instructions for setting up and using a Raspberry Pi with a touchscreen to run Java applications. It outlines downloading and installing Java 8 on the Raspberry Pi, connecting the touchscreen and other hardware, setting up the WiFi connection, and provides an example of running a sample JavaFX application. It also describes additional sensors that can be connected and sample code for interacting with them through the Pi4J library.

1. Java on Raspberry Pi Lab
Stephen Chin
Java Technology Ambassador
JavaOne Content Chair
@steveonjava

2. What Runs Java?

3. =
Have Java With Your Dessert
Raspberry Pi

4. Chalkboard Electronics Touchscreen
 10" or 7" Form Factor
 Connects via HDMI/USB
 Tested with JavaFX 8
 10% Exclusive Discount:
G1F0U796Z083

5. GPIO access

6. How to Setup Your Pi
> Step 1: Install Linux
> Step 2: Download/Copy Java 8 for ARM EA
> Step 3: Deploy and Run JVM Language Apps
http://steveonjava.com/
javafx-on-raspberry-pi-3-easy-steps/

7. Electronic Safety!
> Unplug from wall before wiring
> Get rid of static by touching a metal
surface
> Don't touch exposed wires/metal
> Never remove/insert SD Card while
power is on
7

8. What Comes in Your Lab Kit
1. Touch Screen
2. SD Card
3. Keyboard
4. Yellow Box:
 Power Adapter
 LVDS Cable/Board
 Raspberry Pi Model B
 Mini-USB Cable (power)
 Micro-USB Cable (keyboard)
 Wifi Adapter
Please Save All the Packaging for Later

9. Hooking Up the Pi (Part A)
1. Insert the SD Card in to the Pi
 Will appear upside down when looking at the top
of your Pi
2. Insert the HDMI board into the Pi's HDMI
jack
3. Connect the Pi power to the HDMI board
 Use the Micro USB Cable (short one)
9
Important: Connect everything before plugging into the wall

10. Hooking Up the Pi (Part B)
4. Slide the LCD cable into the back of the display
 Side with gold connectors goes up
 Be careful, the connector is fragile!
5. Insert the wifi adapter into one of the USB ports
6. Hook up the USB keyboard
 Use the Mini USB cable (long one)
7. [Optional ] Connect the USB end to one of the Pi's USB host ports
 This provides touch input – will need to unplug wifi or keyboard
10
Verify connections and plug into power now

11. Is it Working?
> Should get a bunch of flashing LEDs to indicate booting
 Boot takes approx 30 seconds
> The LCD screen should light up
 Might be dim if the light sensor is obstructed
> And you will should see a Linux boot screen with lots of text

12. Logging In
At the login prompt type your username:
> pi
And enter the password:
> raspberry

13. Running the JavaFX Sample Application
Change directory to the project folder
> cd MaryHadALittleLambda
Run the build script
> ant

14. 14

15. Connecting to the Wifi network
> On your computer:
 SSID: NightHacking
 Password: steveonjava
> To get the Pi's ip address
1. Type "ifconfig"
2. Look for the "wlan0" settings
15

16. Downloading Lab Software
> Start a web browser and navigate to the Pi's IP:
 http://10.0.1.xx (something like this)
> Download and install Java 8 SDK
 Make sure you use this SDK for compiling and testing on the Pi
> Grab an SFTP and SSH client if you need one
 Real hackers use the command line!

17. Interacting With Your Pi
> Connect via SSH command line or Putty
 ssh pi@10.0.1.xx
 Password: raspberry
> Connect via SFTP command line or GUI Client
 sftp pi@10.0.1.xx
 Password: raspberry
Accept the generated SSH certificate from your Pi

18. To make an application run
> Build and package your application as a jar
> Copy this to the Raspberry Pi using SFTP
> Execute it via SSH:
> java –jar YourApp.jar
Hacking Time!

19. Stuff to do…
> Changes to MaryHadALittleLambda:
 Change the number of sheep
 Make the rainbow have different colors
 Change the fox size to be fatter/skinnier
 Add new graphics (additional image files under images/extra)
> Playing with hardware
 Pi4j is in /opt/pi4j
 Check out the sample and try blinking the LED (pin wiring is different)
 Come up and get additional hardware to play with
19

20. Pi4J Help
> The samples build script is hardcoded to
/opt/pi4j directory. Easiest fix is to rename
the folder to match this.
> Pi4j needs root access to use GPIO (use
"sudo")
> Debian uses secure paths for sudo by
default. Either disable this, or type the full
path to the java executable (easily
discovered using "which java")
20
LED is on GPIO 7

21. Using the other sensors…
> Read Angela's blog here:
 https://blogs.oracle.com/acaicedo/entry/some_samples_using_gpio_an
d
> Download the source for the…
 Pressure/Temperature sensor:
https://blogs.oracle.com/acaicedo/resource/RPi-HOL/Sensor.java
 Accelerometer/Gyroscope/Compass sensor:
https://blogs.oracle.com/acaicedo/resource/RPi-HOL/Sensor.java
21

22. Stephen Chin
tweet: @steveonjava
blog: http://steveonjava.com
nighthacking.com
Real Geeks
Live Hacking
NightHacking Tour

23. Safe Harbor Statement
The preceding is intended to outline our general product
direction. It is intended for information purposes only, and
may not be incorporated into any contract. It is not a
commitment to deliver any material, code, or functionality,
and should not be relied upon in making purchasing
decisions. The development, release, and timing of any
features or functionality described for Oracle’s products
remains at the sole discretion of Oracle.