throw exception when receiving a mode A/C reply, they can be ignored for now

Author: filipjonckers

gradle.properties

@@ -1,5 +1,5 @@
 GROUP=aero.t2s
-VERSION_NAME=0.2.4-SNAPSHOT
+VERSION_NAME=0.2.5-SNAPSHOT
 
 POM_ARTIFACT_ID=mode-s
 POM_NAME=Mode-S/ADS-B (1090Mhz)

src/main/java/aero/t2s/modes/ModeAcMessageException.java

@@ -0,0 +1,5 @@
+package aero.t2s.modes;
+
+public class ModeAcMessageException extends Exception implements DownlinkException {
+
+}

src/main/java/aero/t2s/modes/ModeSHandler.java

@@ -30,7 +30,11 @@ public void onMessage(Consumer<DownlinkFormat> onMessage) {
     public abstract DownlinkFormat handleSync(String data);
 
 
-    protected short[] toData(final String input) throws EmptyMessageException {
+    protected short[] toData(final String input) throws EmptyMessageException, ModeAcMessageException {
+        if(input.length() == 6) {
+            // example mode A/C: *21D2; *0200; *0101;
+            throw new ModeAcMessageException();
+        }
         if (input.startsWith("*0000")) {
             throw new EmptyMessageException();
         }

src/main/java/aero/t2s/modes/ModeSMessageHandler.java

@@ -38,7 +38,7 @@ public DownlinkFormat handleSync(final String input) {
             }
 
             return df;
-        } catch (EmptyMessageException ignored) {
+        } catch (ModeAcMessageException | EmptyMessageException ignored) {
         } catch (InvalidExtendedSquitterTypeCodeException | UnknownDownlinkFormatException e) {
             LOGGER.error(e.getMessage());
         } catch (Throwable throwable) {

src/main/java/aero/t2s/modes/ModeSTrackHandler.java

@@ -85,7 +85,7 @@ public DownlinkFormat handleSync(final String input) {
             }
 
             return df;
-        } catch (EmptyMessageException ignored) {
+        } catch (ModeAcMessageException | EmptyMessageException ignored) {
         } catch (InvalidExtendedSquitterTypeCodeException | UnknownDownlinkFormatException e) {
             LOGGER.error(e.getMessage());
         } catch (Throwable throwable) {