Raspberry PI и JAVA: пристальный взгляд

Настройка доступа к Raspberry PI по ssh без пароля

$ scp /home/user1/.ssh/id_rsa.pub pi@raspberry_server:~/
$  ssh pi@raspberry_server
$ mkdir .ssh
$ cat ~/id_rsa.pub >> ~/. ssh /authorized_keys

Заглядываем под капот

$ cat /proc/cpuinfo

Features: swp half thumb fastmult vfp edsp java tls

Установка JAVA SE Embedded

$ sudo tar -xvf ejre-7u45-fcs-b15-linux-arm-vfp-hflt-client_headless-26_sep_2013.tar.gz -C /opt

$ sudo chmod a+w /etc/profile
$ echo 'export PATH=/opt/ejre1.7.0_45/bin:$PATH' >> /etc/profile 
$ echo 'export JAVA_HOME=/opt/ejre1.7.0_45' >> /etc/profile 
$ sudo chmod a-w /etc/profile

$ java -version

Тестируем скорость работы

Работа с GPIO

public class Test1 {
 public static void main(String[] args) throws InterruptedException {
 GpioController gpioController = GpioFactory.getInstance();
 GpioPinDigitalOutput gpioPinDigitalOutput = gpioController.provisionDigitalOutputPin(RaspiPin.GPIO_01, "MyLED", PinState.HIGH);
 GpioPinDigitalInput gpioPinDigitalInput = gpioController.provisionDigitalInputPin(RaspiPin.GPIO_02,PinPullResistance.PULL_DOWN);
 gpioPinDigitalInput.addListener(new GpioPinListenerDigital() {
 @Override
 public void handleGpioPinDigitalStateChangeEvent(GpioPinDigitalStateChangeEvent gpioPinDigitalStateChangeEvent) {
 System.out.println("GPIO Pin changed" + gpioPinDigitalStateChangeEvent.getPin() + gpioPinDigitalStateChangeEvent.getState());
 System.out.println("Sleeping 5s");
 try {
 Thread.sleep(5000);
 } catch (InterruptedException e) {
 e.printStackTrace();
 }
 System.out.println("Unsleep");
 }
 });

 while (true) {
 gpioPinDigitalOutput.toggle();
 Thread.sleep(500);
 }


 }
}

$ sudo java

ln -s /opt/ejre1.7.0_45/bin/java /bin/java