added lab15 ex2

src/lab15_observer/ex2/AnalogTimer.java

@@ -0,0 +1,103 @@
+package lab15_observer.ex2;
+
+public class AnalogTimer implements TimerObserver {
+    private final MyTimer timer;
+    private static final String[][] digits = {
+        {
+            "┌─┐",
+            "│ │",
+            "└─┘"
+        },
+        {
+            "  ╷",
+            "  │",
+            "  ╵"
+        },
+        {
+            "╶─┐",
+            "┌─┘",
+            "└─╴"
+        },
+        {
+            "╶─┐",
+            " ─┤",
+            "╶─┘"
+        },
+        {
+            "╷ ╷",
+            "└─┤",
+            "  ╵"
+        },
+        {
+            "┌─╴",
+            "└─┐",
+            "╶─┘"
+        },
+        {
+            "┌─╴",
+            "├─┐",
+            "└─┘"
+        },
+        {
+            "╶─┐",
+            "  │",
+            "  ╵"
+        },
+        {
+            "┌─┐",
+            "├─┤",
+            "└─┘"
+        },
+        {
+            "┌─┐",
+            "└─┤",
+            "╶─┘"
+        },
+    };
+
+    public AnalogTimer(MyTimer timer) {
+        this.timer = timer;
+        timer.registerObserver(this);
+    }
+
+    public void update(int hours, int minutes, int seconds) {
+        String[] lines = {"", "", ""};
+
+        addDigit(lines, hours / 10);
+        addSpace(lines);
+        addDigit(lines, hours % 10);
+
+        addSep(lines);
+
+        addDigit(lines, minutes / 10);
+        addSpace(lines);
+        addDigit(lines, minutes % 10);
+
+        addSep(lines);
+
+        addDigit(lines, seconds / 10);
+        addSpace(lines);
+        addDigit(lines, seconds % 10);
+
+        System.out.println(lines[0]);
+        System.out.println(lines[1]);
+        System.out.println(lines[2]);
+    }
+
+    private void addDigit(String[] lines, int digit) {
+        String[] parts = digits[digit];
+        for (int i = 0; i < 3; i++) {
+            lines[i] += parts[i];
+        }
+    }
+    private void addSpace(String[] lines) {
+        lines[0] += " ";
+        lines[1] += " ";
+        lines[2] += " ";
+    }
+    private void addSep(String[] lines) {
+        lines[0] += " o ";
+        lines[1] += "   ";
+        lines[2] += " o ";
+    }
+}

src/lab15_observer/ex2/ClockTimer.java

@@ -0,0 +1,8 @@
+package lab15_observer.ex2;
+
+public interface ClockTimer {
+    int getHour();
+    int getMinute();
+    int getSecond();
+    void tick();
+}

src/lab15_observer/ex2/DigitalTimer.java

@@ -0,0 +1,15 @@
+package lab15_observer.ex2;
+
+public class DigitalTimer implements TimerObserver {
+    private final MyTimer timer;
+
+    public DigitalTimer(MyTimer timer) {
+        this.timer = timer;
+        timer.registerObserver(this);
+    }
+
+    @Override
+    public void update(int hours, int minutes, int seconds) {
+        System.out.printf("Time: %02d:%02d:%02d%n", hours, minutes, seconds);
+    }
+}

src/lab15_observer/ex2/Main.java

@@ -0,0 +1,10 @@
+package lab15_observer.ex2;
+
+public class Main {
+    public static void main(String[] args) {
+        MyTimer clockTimer = new MyTimer();
+
+        new AnalogTimer(clockTimer);
+        new DigitalTimer(clockTimer);
+    }
+}

src/lab15_observer/ex2/MyTimer.java

@@ -0,0 +1,53 @@
+package lab15_observer.ex2;
+
+import java.util.*;
+
+public class MyTimer implements ClockTimer {
+    private final List<TimerObserver> observers = new ArrayList<>();
+    private Calendar cal;
+    private Timer timer;
+
+    public MyTimer() {
+        cal = Calendar.getInstance();
+        timer = new Timer();
+        timer.schedule(new TimerAction(), 0, 1000);
+    }
+
+    class TimerAction extends TimerTask {
+        @Override
+        public void run() {
+            cal = Calendar.getInstance();
+            tick();
+        }
+    }
+
+    @Override
+    public int getHour() {
+        return cal.get(Calendar.HOUR_OF_DAY);
+    }
+
+    @Override
+    public int getMinute() {
+        return cal.get(Calendar.MINUTE);
+    }
+
+    @Override
+    public int getSecond() {
+        return cal.get(Calendar.SECOND);
+    }
+
+    @Override
+    public void tick() {
+        for (TimerObserver o : observers) {
+            o.update(getHour(), getMinute(), getSecond());
+        }
+    }
+
+    public void registerObserver(TimerObserver o) {
+        observers.add(o);
+    }
+
+    public void removeObserver(TimerObserver o) {
+        observers.remove(o);
+    }
+}

src/lab15_observer/ex2/TimerObserver.java

@@ -0,0 +1,5 @@
+package lab15_observer.ex2;
+
+public interface TimerObserver{
+    void update(int hours, int minutes, int seconds);
+}