Data commit

Task/Nautical-bell/Java/nautical-bell.java

@@ -0,0 +1,50 @@
+import java.text.DateFormat;
+import java.text.SimpleDateFormat;
+import java.util.TimeZone;
+
+public class NauticalBell extends Thread {
+
+    public static void main(String[] args) {
+        NauticalBell bells = new NauticalBell();
+        bells.setDaemon(true);
+        bells.start();
+        try {
+            bells.join();
+        } catch (InterruptedException e) {
+            System.out.println(e);
+        }
+    }
+
+    @Override
+    public void run() {
+        DateFormat sdf = new SimpleDateFormat("HH:mm:ss");
+        sdf.setTimeZone(TimeZone.getTimeZone("UTC"));
+
+        int numBells = 0;
+        long time = System.currentTimeMillis();
+        long next = time - (time % (24 * 60 * 60 * 1000)); // midnight
+
+        while (next < time) {
+            next += 30 * 60 * 1000; // 30 minutes
+            numBells = 1 + (numBells % 8);
+        }
+
+        while (true) {
+            long wait = 100L;
+            time = System.currentTimeMillis();
+            if (time - next >= 0) {
+                String bells = numBells == 1 ? "bell" : "bells";
+                String timeString = sdf.format(time);
+                System.out.printf("%s : %d %s\n", timeString, numBells, bells);
+                next += 30 * 60 * 1000;
+                wait = next - time;
+                numBells = 1 + (numBells % 8);
+            }
+            try {
+                Thread.sleep(wait);
+            } catch (InterruptedException e) {
+                return;
+            }
+        }
+    }
+}