added lab12 ex1

src/lab12_singleton/ex1/CarSensorSingletonLauncher.java

@@ -0,0 +1,29 @@
+package lab12_singleton.ex1;
+
+import lab12_singleton.ex1.sensors.*;
+import lab12_singleton.ex1.managers.*;
+
+public class CarSensorSingletonLauncher {
+    public CarSensorSingletonLauncher() {
+
+    }
+
+    public static void main(String[] args) {
+        CarSensorSingletonLauncher launcher = new CarSensorSingletonLauncher();
+        launcher.launch();
+    }
+
+    public void launch() {
+        this.test(SimpleSingletonSensorsManager.getInstance());
+        this.test(SynchSingletonSensorsManager.getInstance());
+        this.test(EagerSingletonSensorsManager.getInstance());
+        this.test(DbleCheckedSingletonSensorsManager.getInstance());
+    }
+
+    private void test(SingletonSensorManager manager) {
+        manager.addSensor(new TemperatureSensor());
+        manager.addSensor(new SpeedSensor());
+        manager.addSensor(new RoadConditionSensor());
+        manager.printState();
+    }
+}

src/lab12_singleton/ex1/Sensor.java

@@ -0,0 +1,15 @@
+package lab12_singleton.ex1;
+
+public abstract class Sensor {
+    private boolean ok = true;
+
+    public abstract String getName();
+    public void setOk(boolean ok) {
+        this.ok = ok;
+    }
+
+    @Override
+    public String toString() {
+        return getName() + ": " + (ok ? "Ok" : "Warning");
+    }
+}

src/lab12_singleton/ex1/SingletonSensorManager.java

@@ -0,0 +1,17 @@
+package lab12_singleton.ex1;
+
+import java.util.ArrayList;
+
+public abstract class SingletonSensorManager {
+    private final ArrayList<Sensor> sensors = new ArrayList<>();
+
+    protected SingletonSensorManager() {}
+
+    public void addSensor(Sensor sensor) {
+        sensors.add(sensor);
+    }
+
+    public void printState() {
+        System.out.println("<" + this.getClass().getSimpleName() + ": " + sensors.toString() + ">");
+    }
+}

src/lab12_singleton/ex1/managers/DbleCheckedSingletonSensorsManager.java

@@ -0,0 +1,18 @@
+package lab12_singleton.ex1.managers;
+
+import lab12_singleton.ex1.SingletonSensorManager;
+
+public class DbleCheckedSingletonSensorsManager extends SingletonSensorManager {
+    private static DbleCheckedSingletonSensorsManager instance;
+
+    public static DbleCheckedSingletonSensorsManager getInstance() {
+        if (instance == null) {
+            synchronized (DbleCheckedSingletonSensorsManager.class) {
+                if (instance == null) {
+                    instance = new DbleCheckedSingletonSensorsManager();
+                }
+            }
+        }
+        return instance;
+    }
+}

src/lab12_singleton/ex1/managers/EagerSingletonSensorsManager.java

@@ -0,0 +1,11 @@
+package lab12_singleton.ex1.managers;
+
+import lab12_singleton.ex1.SingletonSensorManager;
+
+public class EagerSingletonSensorsManager extends SingletonSensorManager {
+    private static final EagerSingletonSensorsManager instance = new EagerSingletonSensorsManager();
+
+    public static EagerSingletonSensorsManager getInstance() {
+        return instance;
+    }
+}

src/lab12_singleton/ex1/managers/SimpleSingletonSensorsManager.java

@@ -0,0 +1,14 @@
+package lab12_singleton.ex1.managers;
+
+import lab12_singleton.ex1.SingletonSensorManager;
+
+public class SimpleSingletonSensorsManager extends SingletonSensorManager {
+    private static SimpleSingletonSensorsManager instance;
+
+    public static SingletonSensorManager getInstance() {
+        if (instance == null) {
+            instance = new SimpleSingletonSensorsManager();
+        }
+        return instance;
+    }
+}

src/lab12_singleton/ex1/managers/SynchSingletonSensorsManager.java

@@ -0,0 +1,14 @@
+package lab12_singleton.ex1.managers;
+
+import lab12_singleton.ex1.SingletonSensorManager;
+
+public class SynchSingletonSensorsManager extends SingletonSensorManager {
+    private static SynchSingletonSensorsManager instance;
+
+    public static synchronized SynchSingletonSensorsManager getInstance() {
+        if (instance == null) {
+            instance = new SynchSingletonSensorsManager();
+        }
+        return instance;
+    }
+}

src/lab12_singleton/ex1/sensors/RoadConditionSensor.java

@@ -0,0 +1,10 @@
+package lab12_singleton.ex1.sensors;
+
+import lab12_singleton.ex1.Sensor;
+
+public class RoadConditionSensor extends Sensor {
+    @Override
+    public String getName() {
+        return "Road Condition";
+    }
+}

src/lab12_singleton/ex1/sensors/SpeedSensor.java

@@ -0,0 +1,10 @@
+package lab12_singleton.ex1.sensors;
+
+import lab12_singleton.ex1.Sensor;
+
+public class SpeedSensor extends Sensor {
+    @Override
+    public String getName() {
+        return "Speed";
+    }
+}

src/lab12_singleton/ex1/sensors/TemperatureSensor.java

@@ -0,0 +1,10 @@
+package lab12_singleton.ex1.sensors;
+
+import lab12_singleton.ex1.Sensor;
+
+public class TemperatureSensor extends Sensor {
+    @Override
+    public String getName() {
+        return "Temperature";
+    }
+}