Fix DX Cluster spot formatting - emit fixed 75-character DXSpider-compatible lines - align callsign, comment, and UTC fields - support frequencies up to 24 GHz - reject overlong callsigns instead of truncating them - add protocol tests and update documentation Fixes #86

2026-09-12 12:15:33 +02:00 · 2026-09-02 20:03:55 +02:00
parent 6b0d699a98
commit 51aa04bfb5
15 changed files with 422 additions and 77 deletions
@@ -0,0 +1,165 @@
+package kst4contest.controller;
+
+import java.nio.charset.StandardCharsets;
+import java.util.Locale;
+
+/**
+ * Formats local DX Cluster spots using the fixed-column layout emitted by
+ * DXSpider and accepted by common logging programs.
+ */
+final class DXClusterSpotFormatter {
+
+    /** Length of the DX Cluster line before BEL and CRLF framing. */
+    /* package */
+    static final int LINE_LENGTH = 75;
+    /** One-based column in which the spotted callsign starts. */
+    /* package */
+    static final int DX_CALL_COLUMN = 27;
+    /** Width of the fixed comment field. */
+    /* package */
+    static final int COMMENT_LENGTH = 30;
+    /** One-based column in which the UTC time starts. */
+    /* package */
+    static final int TIME_COLUMN = 71;
+
+    /** Zero-based exclusive end position of the frequency field. */
+    private static final int FREQUENCY_END = 24;
+    /** Maximum width of the spotted callsign field. */
+    private static final int DX_CALL_LENGTH = 12;
+    /** Required width of the HHMMZ time field. */
+    private static final int TIME_LENGTH = 5;
+    /** Minimum separator width between spotter and frequency. */
+    private static final int MIN_FREQUENCY_GAP = 1;
+    /** Wire framing appended to every formatted line. */
+    private static final String PAYLOAD_SUFFIX = "\u0007\u0007\r\n";
+
+    private DXClusterSpotFormatter() {
+    }
+
+    /** Builds the fixed 75-character payload line without wire framing. */
+    /* package */
+    static String formatLine(
+            final String spotterCallSign,
+            final String frequency,
+            final String dxCallSign,
+            final String comment,
+            final String time
+    ) {
+        final String spotter = requireValue(
+                spotterCallSign,
+                "spotter callsign"
+        )
+                .toUpperCase(Locale.ROOT);
+        final String frequencyValue = requireValue(frequency, "frequency");
+        final String dxCall = requireValue(dxCallSign, "DX callsign")
+                .toUpperCase(Locale.ROOT);
+        final String timeValue = requireValue(time, "time");
+
+        validateDxCall(dxCall);
+        validateTime(timeValue);
+
+        final String prefix = "DX de " + spotter + ":";
+        final int frequencyPadding = calculateFrequencyPadding(
+                prefix,
+                frequencyValue
+        );
+        final String normalizedComment = normalizeComment(comment);
+
+        final String line = prefix
+                + " ".repeat(frequencyPadding)
+                + frequencyValue
+                + "  "
+                + padRight(dxCall, DX_CALL_LENGTH)
+                + " "
+                + padRight(normalizedComment, COMMENT_LENGTH)
+                + " "
+                + timeValue;
+
+        if (line.length() != LINE_LENGTH) {
+            throw new IllegalStateException(
+                    "DX Cluster formatter produced "
+                            + line.length()
+                            + " characters instead of "
+                            + LINE_LENGTH
+            );
+        }
+
+        return line;
+    }
+
+    /** Builds one complete ASCII spot payload including BEL and CRLF framing. */
+    /* package */
+    static byte[] formatPayload(
+            final String spotterCallSign,
+            final String frequency,
+            final String dxCallSign,
+            final String comment,
+            final String time
+    ) {
+        return (formatLine(
+                spotterCallSign,
+                frequency,
+                dxCallSign,
+                comment,
+                time
+        ) + PAYLOAD_SUFFIX).getBytes(StandardCharsets.US_ASCII);
+    }
+
+    private static void validateDxCall(final String dxCall) {
+        if (dxCall.length() > DX_CALL_LENGTH) {
+            throw new IllegalArgumentException(
+                    "DX callsign exceeds 12 characters: " + dxCall
+            );
+        }
+    }
+
+    private static void validateTime(final String time) {
+        if (time.length() != TIME_LENGTH) {
+            throw new IllegalArgumentException(
+                    "DX Cluster time must contain exactly five characters"
+            );
+        }
+    }
+
+    private static int calculateFrequencyPadding(
+            final String prefix,
+            final String frequency
+    ) {
+        final int padding = FREQUENCY_END
+                - prefix.length()
+                - frequency.length();
+
+        if (padding < MIN_FREQUENCY_GAP) {
+            throw new IllegalArgumentException(
+                    "Spotter callsign and frequency do not fit the DX Cluster prefix"
+            );
+        }
+
+        return padding;
+    }
+
+    private static String normalizeComment(final String comment) {
+        final String normalized = comment == null ? "" : comment.trim();
+
+        return normalized.length() > COMMENT_LENGTH
+                ? normalized.substring(0, COMMENT_LENGTH)
+                : normalized;
+    }
+
+    private static String requireValue(
+            final String value,
+            final String fieldName
+    ) {
+        if (value == null || value.isBlank()) {
+            throw new IllegalArgumentException(
+                    "DX Cluster " + fieldName + " is missing"
+            );
+        }
+
+        return value.trim();
+    }
+
+    private static String padRight(final String value, final int length) {
+        return value + " ".repeat(length - value.length());
+    }
+}
@@ -152,6 +152,7 @@ public class DXClusterThreadPooledServer implements Runnable {
    public boolean broadcastSingleDXClusterEntryToLoggers(
            ChatMember chatMember
    ) {
+        final byte[] clusterPayload;
        final String clusterMessage;

        try {
@@ -162,24 +163,27 @@ public class DXClusterThreadPooledServer implements Runnable {
                            .getNotify_optionalFrequencyPrefix()
            );

-            clusterMessage =
-                    "DX de "
-                            + chatController
+            clusterPayload = DXClusterSpotFormatter.formatPayload(
+                    chatController
                            .getChatPreferences()
                            .getNotify_DXCSrv_SpottersCallSign()
-                            .getValue()
-                            + ":   "
-                            + frequency
-                            + "  "
-                            + chatMember.getCallSign().toUpperCase()
-                            + "             "
-                            + chatMember.getQra().toUpperCase()
-                            + "  "
-                            + new Utils4KST()
+                            .getValue(),
+                    frequency,
+                    chatMember.getCallSign(),
+                    chatMember.getQra(),
+                    new Utils4KST()
                            .time_generateCurrenthhmmZTimeStringForClusterMessage()
-                            + ((char) 7)
-                            + ((char) 7)
-                            + "\r\n";
+            );
+            clusterMessage = new String(
+                    clusterPayload,
+                    StandardCharsets.US_ASCII
+            );
+        } catch (IllegalArgumentException exception) {
+            LOGGER.log(
+                    Level.WARNING,
+                    "DX Cluster spot rejected: " + exception.getMessage()
+            );
+            return false;
        } catch (Exception exception) {
            LOGGER.log(
                    Level.SEVERE,
@@ -204,11 +208,7 @@ public class DXClusterThreadPooledServer implements Runnable {

                try {
                    OutputStream output = socket.getOutputStream();
-                    output.write(
-                            clusterMessage.getBytes(
-                                    StandardCharsets.US_ASCII
-                            )
-                    );
+                    output.write(clusterPayload);
                    output.flush();
                    deliveredClients++;
                } catch (IOException exception) {
@@ -360,4 +360,4 @@ class DXClusterServerWorkerRunnable implements Runnable {
            }
        }
    }
-}
+}
@@ -1,44 +0,0 @@
-package kst4contest.controller;
-
-import javafx.beans.property.SimpleStringProperty;
-import kst4contest.model.ChatMember;
-import kst4contest.model.ChatPreferences;
-
-public class DXClusterThreadPooledServerTest {
-
-    public static void main(String[] args) {
-
-        ChatController client = new ChatController();
-        ChatPreferences testPreferences = new ChatPreferences();
-        testPreferences.setStn_loginCallSign("DM5M");
-
-        client.setChatPreferences(testPreferences);
-        DXClusterThreadPooledServer dxClusterServer = new DXClusterThreadPooledServer(8000, client, client);
-
-        new Thread(dxClusterServer).start();
-
-
-        try {
-            Thread.sleep(10 * 1000);
-            System.out.println(">>>>>>>>>>>>>>>>>>>>>>>>ready.....go!");
-        } catch (InterruptedException e) {
-            e.printStackTrace();
-        }
-
-        ChatMember test = new ChatMember();
-        test.setCallSign("DL5ASG");
-        test.setQra("JO51HK");
-        test.setFrequency(new SimpleStringProperty("144776.0"));
-
-        dxClusterServer.broadcastSingleDXClusterEntryToLoggers(test);
-
-
-//        try {
-//            Thread.sleep(20 * 3333);
-//        } catch (InterruptedException e) {
-//            e.printStackTrace();
-//        }
-//        System.out.println("Stopping Server");
-//        server.stop();
-    }
-}
@@ -1847,14 +1847,14 @@ public class MessageBusManagementThread extends Thread {
 	 * @param sender station for which the DX Cluster spot is generated
 	 * @return locator with up to two optional AP entries
 	 */
-	private String buildDxClusterSpotComment(ChatMember sender) {
+	static String buildDxClusterSpotComment(ChatMember sender) {
 		if (sender == null) {
 			return "";
 		}

 		String locator = sender.getQra() == null
 				? ""
-				: sender.getQra().trim();
+				: sender.getQra().trim().toUpperCase(Locale.ROOT);

 		AirPlaneReflectionInfo reflectionInfo =
 				sender.getAirPlaneReflectInfo();
@@ -1882,7 +1882,7 @@ public class MessageBusManagementThread extends Thread {

 			aircraftComments.add(
 					aircraft.getArrivingDurationMinutes()
-							+ "min, "
+							+ "m/"
 							+ aircraft.getPotential()
 							+ "%"
 			);
@@ -1893,11 +1893,11 @@ public class MessageBusManagementThread extends Thread {
 		}

 		String apComment =
-				"AP: " + String.join("; ", aircraftComments);
+				"AP " + String.join(";", aircraftComments);

 		return locator.isEmpty()
 				? apComment
-				: locator + " , " + apComment;
+				: locator + " " + apComment;
 	}

 	/**
@@ -10736,7 +10736,7 @@ public class Kst4ContestApplication extends Application implements StatusUpdateL
 					testSpot.setFrequency(
 							new SimpleStringProperty("300")
 					);
-					testSpot.setQra("Testing DXC-Spot: Congrats, you donated $100!");
+					testSpot.setQra("DXC test: You donated $100!");
 					testSpot.setCallSign("DO5AMF");

 					if (!dxClusterServer
@@ -0,0 +1,138 @@
+package kst4contest.controller;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+import java.nio.charset.StandardCharsets;
+import java.util.stream.Stream;
+
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.Arguments;
+import org.junit.jupiter.params.provider.MethodSource;
+
+class DXClusterSpotFormatterTest {
+
+    @ParameterizedTest
+    @MethodSource("supportedFrequencies")
+    void keepsFixedColumnsAcrossSupportedFrequencies(
+            String spotter,
+            String frequency
+    ) {
+        String line = DXClusterSpotFormatter.formatLine(
+                spotter,
+                frequency,
+                "DL5ASG",
+                "JO51HK",
+                "1234Z"
+        );
+
+        assertEquals(DXClusterSpotFormatter.LINE_LENGTH, line.length());
+        assertEquals(
+                "DL5ASG",
+                line.substring(
+                        DXClusterSpotFormatter.DX_CALL_COLUMN - 1,
+                        DXClusterSpotFormatter.DX_CALL_COLUMN - 1 + 6
+                )
+        );
+        assertEquals(
+                "JO51HK",
+                line.substring(39, 45)
+        );
+        assertEquals(
+                "1234Z",
+                line.substring(DXClusterSpotFormatter.TIME_COLUMN - 1)
+        );
+        assertEquals(
+                frequency,
+                line.substring(0, 24).trim().replaceFirst("^DX de .+?:\\s*", "")
+        );
+    }
+
+    @Test
+    void padsShortCommentsAndTruncatesLongCommentsToThirtyCharacters() {
+        String shortLine = DXClusterSpotFormatter.formatLine(
+                "DM5M",
+                "144205.0",
+                "DL5ASG",
+                "JO51HK",
+                "1234Z"
+        );
+        String longLine = DXClusterSpotFormatter.formatLine(
+                "DM5M",
+                "144205.0",
+                "DL5ASG",
+                "123456789012345678901234567890EXTRA",
+                "1234Z"
+        );
+
+        assertEquals(
+                "JO51HK" + " ".repeat(24),
+                shortLine.substring(39, 69)
+        );
+        assertEquals(
+                "123456789012345678901234567890",
+                longLine.substring(39, 69)
+        );
+    }
+
+    @Test
+    void keepsVariableDxCallsignsWithoutMovingTheComment() {
+        String twelveCharacterLine = DXClusterSpotFormatter.formatLine(
+                "DO5AMF",
+                "24048100.0",
+                "ABCDEFGHIJKL",
+                "JO51HK AP 1m/100%;4m/75%",
+                "2359Z"
+        );
+
+        assertEquals("ABCDEFGHIJKL", twelveCharacterLine.substring(26, 38));
+        assertEquals(
+                "JO51HK AP 1m/100%;4m/75%" + " ".repeat(6),
+                twelveCharacterLine.substring(39, 69)
+        );
+        assertThrows(
+                IllegalArgumentException.class,
+                () -> DXClusterSpotFormatter.formatLine(
+                        "DO5AMF",
+                        "144205.0",
+                        "ABCDEFGHIJKLM",
+                        "JO51HK",
+                        "2359Z"
+                )
+        );
+    }
+
+    @Test
+    void appendsExactlyTwoBellCharactersAndCrlf() {
+        byte[] payload = DXClusterSpotFormatter.formatPayload(
+                "DM5M",
+                "50200.0",
+                "DL5ASG",
+                "JO51HK",
+                "0000Z"
+        );
+
+        assertEquals(DXClusterSpotFormatter.LINE_LENGTH + 4, payload.length);
+        assertEquals(7, payload[75]);
+        assertEquals(7, payload[76]);
+        assertEquals('\r', payload[77]);
+        assertEquals('\n', payload[78]);
+        assertEquals(
+                75,
+                new String(payload, 0, 75, StandardCharsets.US_ASCII).length()
+        );
+    }
+
+    private static Stream<Arguments> supportedFrequencies() {
+        return Stream.of(
+                Arguments.of("DM5M", "50200.0"),
+                Arguments.of("DO5AMF", "70250.0"),
+                Arguments.of("DM5M", "144205.0"),
+                Arguments.of("DO5AMF", "432088.0"),
+                Arguments.of("DM5M", "1296338.0"),
+                Arguments.of("DO5AMF", "10368100.0"),
+                Arguments.of("DO5AMF", "24048100.0")
+        );
+    }
+}
@@ -0,0 +1,51 @@
+package kst4contest.controller;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import javafx.collections.FXCollections;
+import kst4contest.model.AirPlane;
+import kst4contest.model.AirPlaneReflectionInfo;
+import kst4contest.model.ChatMember;
+import org.junit.jupiter.api.Test;
+
+class MessageBusManagementThreadDxClusterCommentTest {
+
+    @Test
+    void keepsLocatorAndAddsCompactAirScoutInformation() {
+        ChatMember sender = new ChatMember();
+        sender.setQra("jo51hk");
+
+        AirPlane firstAircraft = new AirPlane();
+        firstAircraft.setArrivingDurationMinutes(1);
+        firstAircraft.setPotential(100);
+
+        AirPlane secondAircraft = new AirPlane();
+        secondAircraft.setArrivingDurationMinutes(4);
+        secondAircraft.setPotential(75);
+
+        AirPlaneReflectionInfo reflectionInfo = new AirPlaneReflectionInfo();
+        reflectionInfo.setRisingAirplanes(
+                FXCollections.observableArrayList(
+                        firstAircraft,
+                        secondAircraft
+                )
+        );
+        sender.setAirPlaneReflectInfo(reflectionInfo);
+
+        assertEquals(
+                "JO51HK AP 1m/100%;4m/75%",
+                MessageBusManagementThread.buildDxClusterSpotComment(sender)
+        );
+    }
+
+    @Test
+    void returnsLocatorWhenAirScoutInformationIsMissing() {
+        ChatMember sender = new ChatMember();
+        sender.setQra("JO51HK");
+
+        assertEquals(
+                "JO51HK",
+                MessageBusManagementThread.buildDxClusterSpotComment(sender)
+        );
+    }
+}