dependency to pi4j and basic example added

Author: DieterHolz

build.gradle

@@ -8,8 +8,12 @@ group 'ch.fhnw'
 version '0.1'
 
 repositories {
-	jcenter();
+	jcenter()
     mavenCentral()
+	maven {
+		url "https://oss.sonatype.org/content/repositories/snapshots/"
+	}
+
 }
 
 
@@ -28,6 +32,8 @@ compileJava {
 }
 
 dependencies {
+	implementation 'com.pi4j:pi4j-core:1.4-SNAPSHOT'
+
 	testImplementation('org.junit.jupiter:junit-jupiter:5.6.0')
 }
 

src/main/java/gpiosimulator/HelloGPIO.java

@@ -0,0 +1,54 @@
+package gpiosimulator;
+
+import com.pi4j.io.gpio.GpioController;
+import com.pi4j.io.gpio.GpioFactory;
+import com.pi4j.io.gpio.GpioPinDigitalInput;
+import com.pi4j.io.gpio.GpioPinDigitalOutput;
+import com.pi4j.io.gpio.GpioPinPwmOutput;
+import com.pi4j.io.gpio.PinPullResistance;
+import com.pi4j.io.gpio.PinState;
+import com.pi4j.io.gpio.RaspiBcmPin;
+import com.pi4j.io.gpio.RaspiGpioProvider;
+import com.pi4j.io.gpio.RaspiPinNumberingScheme;
+import com.pi4j.io.gpio.event.GpioPinListenerDigital;
+import com.pi4j.util.Console;
+
+public class HelloGPIO {
+
+    public static void main(String[] args) throws Exception {
+        GpioFactory.setDefaultProvider(new RaspiGpioProvider(RaspiPinNumberingScheme.BROADCOM_PIN_NUMBERING)); //like on GPIO Extension Board
+
+        final GpioController gpio = GpioFactory.getInstance();
+
+        GpioPinDigitalOutput led = gpio.provisionDigitalOutputPin(RaspiBcmPin.GPIO_16, // PIN NUMBER
+                                                                  "My LED" ,           // PIN FRIENDLY NAME (optional)
+                                                                   PinState.LOW);      // PIN STARTUP STATE (optional)
+
+
+        led.setShutdownOptions(true, PinState.LOW);
+
+        final GpioPinDigitalInput button = gpio.provisionDigitalInputPin(RaspiBcmPin.GPIO_05,
+                                                                         PinPullResistance.PULL_DOWN);
+
+        // set shutdown state for this input pin
+        button.setShutdownOptions(true);
+
+        button.addListener((GpioPinListenerDigital) event -> {
+            if(event.getState().isHigh()){
+                led.high();
+            }
+            else {
+                led.low();
+            }
+        });
+
+        Console console = new Console();
+        console.promptForExit();
+
+        while (console.isRunning()) {
+            Thread.sleep(1000);
+        }
+
+        gpio.shutdown();
+    }
+}