30 operational status v1

src/main/java/de/serosystems/example/ExampleDecoder.java

@@ -215,7 +215,6 @@ public void decodeMsg(long timestamp, String raw, Position receiver) {
 				AirborneOperationalStatusV1Msg opstatA1 = (AirborneOperationalStatusV1Msg) msg;
 				System.out.println("["+icao24+"]: Using ADS-B version "+opstatA1.getVersion());
 				System.out.println("          Barometric altitude cross-checked: "+opstatA1.getBarometricAltitudeIntegrityCode());
-				System.out.println("          Gemoetric vertical accuracy: "+opstatA1.getGeometricVerticalAccuracy()+"m");
 
 				if (opstatA1.getHorizontalReferenceDirection())
 					System.out.println("          Horizontal reference: true north");
@@ -225,18 +224,18 @@ public void decodeMsg(long timestamp, String raw, Position receiver) {
 				System.out.println("          Position Uncertainty (based on NACp): " + opstatA1.getPositionUncertainty());
 				System.out.println("          Has NIC supplement A: " + opstatA1.hasNICSupplementA());
 				System.out.println("          Surveillance/Source Integrity Level (SIL): " + opstatA1.getSIL());
-				System.out.println("          System design assurance: " + opstatA1.getSystemDesignAssurance());
-				System.out.println("          Has 1090ES in: " + opstatA1.has1090ESIn());
+				System.out.println("          Has 1090 ES In: " + opstatA1.has1090ESIn());
 				System.out.println("          IDENT switch active: " + opstatA1.hasActiveIDENTSwitch());
 				System.out.println("          Has operational TCAS: " + opstatA1.hasOperationalTCAS());
 				System.out.println("          Has TCAS resolution advisory: " + opstatA1.hasTCASResolutionAdvisory());
-				System.out.println("          Has UAT in: " + opstatA1.hasUATIn());
-				System.out.println("          Uses single antenna: " + opstatA1.hasSingleAntenna());
 				System.out.println("          Supports air-referenced velocity reports: " + opstatA1.hasAirReferencedVelocity());
 
-				// SIL supplement in version 2
 				if (msg instanceof AirborneOperationalStatusV2Msg) {
+					System.out.println("          Gemoetric vertical accuracy: "+((AirborneOperationalStatusV2Msg) msg).getGeometricVerticalAccuracy()+"m");
+					System.out.println("          System design assurance: " + ((AirborneOperationalStatusV2Msg) msg).getSystemDesignAssurance());
+					System.out.println("          Has UAT in: " + ((AirborneOperationalStatusV2Msg) msg).hasUATIn());
 					System.out.println("          Has SIL supplement: " + ((AirborneOperationalStatusV2Msg) msg).hasSILSupplement());
+					System.out.println("          Uses single antenna: " + ((AirborneOperationalStatusV2Msg) msg).hasSingleAntenna());
 				}
 
 				break;
@@ -245,7 +244,6 @@ public void decodeMsg(long timestamp, String raw, Position receiver) {
 				SurfaceOperationalStatusV1Msg opstatS1 = (SurfaceOperationalStatusV1Msg) msg;
 
 				System.out.println("["+icao24+"]: Using ADS-B version "+opstatS1.getVersion());
-				System.out.println("          Gemoetric vertical accuracy: "+opstatS1.getGeometricVerticalAccuracy()+"m");
 
 				if (opstatS1.getHorizontalReferenceDirection())
 					System.out.println("          Horizontal reference: true north");
@@ -254,24 +252,23 @@ public void decodeMsg(long timestamp, String raw, Position receiver) {
 				System.out.println("          Navigation Accuracy Category for position (NACp): " + opstatS1.getNACp());
 				System.out.println("          Position Uncertainty (based on NACp): " + opstatS1.getPositionUncertainty());
 				System.out.println("          Has NIC supplement A: " + opstatS1.hasNICSupplementA());
-				System.out.println("          Has NIC supplement C: " + opstatS1.getNICSupplementC());
 				System.out.println("          Surveillance/Source Integrity Level (SIL): " + opstatS1.getSIL());
-				System.out.println("          System design assurance: " + opstatS1.getSystemDesignAssurance());
-				System.out.println("          Has 1090ES in: " + opstatS1.has1090ESIn());
+				System.out.println("          Has 1090 ES In: " + opstatS1.has1090ESIn());
 				System.out.println("          IDENT switch active: " + opstatS1.hasActiveIDENTSwitch());
 				System.out.println("          Has TCAS resolution advisory: " + opstatS1.hasTCASResolutionAdvisory());
-				System.out.println("          Has UAT in: " + opstatS1.hasUATIn());
-				System.out.println("          Uses single antenna: " + opstatS1.hasSingleAntenna());
 				System.out.println("          Airplane length: " + opstatS1.getAirplaneLength() + "m");
 				System.out.println("          Airplane width: " + opstatS1.getAirplaneWidth() + "m");
-				System.out.println("          Navigation Accuracy Category for velocity (NACv): " + opstatS1.getNACv());
 				System.out.println("          Low (<70W) TX power: " + opstatS1.hasLowTxPower());
-				System.out.println("          Encoded GPS antenna offset: " + opstatS1.getGPSAntennaOffset());
 				System.out.println("          Has track heading info: " + opstatS1.hasTrackHeadingInfo());
 
-				// SIL supplement in version 2
 				if (msg instanceof SurfaceOperationalStatusV2Msg) {
+					System.out.println("          Has NIC supplement C: " + ((SurfaceOperationalStatusV2Msg) msg).getNICSupplementC());
+					System.out.println("          System design assurance: " + ((SurfaceOperationalStatusV2Msg) msg).getSystemDesignAssurance());
+					System.out.println("          Navigation Accuracy Category for velocity (NACv): " + ((SurfaceOperationalStatusV2Msg) msg).getNACv());
 					System.out.println("          Has SIL supplement: " + ((SurfaceOperationalStatusV2Msg) msg).hasSILSupplement());
+					System.out.println("          Has UAT in: " + ((SurfaceOperationalStatusV2Msg) msg).hasUATIn());
+					System.out.println("          Encoded GPS antenna offset: " + ((SurfaceOperationalStatusV2Msg) msg).getGPSAntennaOffset());
+					System.out.println("          Uses single antenna: " + ((SurfaceOperationalStatusV2Msg) msg).hasSingleAntenna());
 				}
 
 				break;

src/main/java/de/serosystems/lib1090/StatefulModeSDecoder.java

@@ -216,7 +216,6 @@ public ModeSDownlinkMsg decode(ModeSDownlinkMsg modes, long timestamp) throws Ba
 								case 1:
 									SurfaceOperationalStatusV1Msg s1 = new SurfaceOperationalStatusV1Msg(es1090);
 									dd.nicSupplA = s1.hasNICSupplementA();
-									dd.nicSupplC = s1.getNICSupplementC();
 									return s1;
 								case 2:
 									SurfaceOperationalStatusV2Msg s2 = new SurfaceOperationalStatusV2Msg(es1090);

src/main/java/de/serosystems/lib1090/decoding/BitReader.java

@@ -0,0 +1,124 @@
+package de.serosystems.lib1090.decoding;
+
+import java.util.Objects;
+
+/**
+ * A stateless utility for extracting bits from byte arrays using absolute bit ranges.
+ * <p>
+ * <b>Indexing Convention:</b> This class uses <b>1-based indexing</b> to match
+ * technical specifications like ICAO Annex 10.
+ * <ul>
+ * <li>Bit 1: The Most Significant Bit (MSB) of the first byte.</li>
+ * <li>Bit 8: The Least Significant Bit (LSB) of the first byte.</li>
+ * <li>Bit 9: The MSB of the second byte.</li>
+ * </ul>
+ * <p>
+ * Example: {@code readInt(1, 5)} extracts the first 5 bits of the message.
+ */
+public class BitReader {
+	private final byte[] data;
+	private final boolean bigEndian;
+
+	private BitReader(byte[] data, boolean bigEndian) {
+		this.data = Objects.requireNonNull(data);
+		this.bigEndian = bigEndian;
+	}
+
+	/**
+	 * Factory for Big-Endian bit ordering (Network Byte Order).
+	 * Bit 1 is the MSB of data[0].
+	 */
+	public static BitReader forBigEndian(byte[] data) {
+		return new BitReader(data, true);
+	}
+
+	/**
+	 * Factory for Little-Endian bit ordering.
+	 * Bit 1 is the LSB of data[0].
+	 */
+	public static BitReader forLittleEndian(byte[] data) {
+		return new BitReader(data, false);
+	}
+
+	public byte readByte(int from, int to) {
+		return (byte) readRange(from, to, 8);
+	}
+
+	public short readShort(int from, int to) {
+		return (short) readRange(from, to, 16);
+	}
+
+	public int readInt(int from, int to) {
+		return (int) readRange(from, to, 32);
+	}
+
+	public long readLong(int from, int to) {
+		return readRange(from, to, 64);
+	}
+
+	/**
+	 * Internal extraction logic.
+	 * * @param from    The starting bit position (inclusive, starts at 1).
+	 *
+	 * @param to      The ending bit position (inclusive, starts at 1).
+	 * @param maxBits Maximum allowed bit span for the return type.
+	 * @return The extracted value as a long.
+	 */
+	private long readRange(int from, int to, int maxBits) {
+		if (from < 1) {
+			throw new IllegalArgumentException("Start bit must be >= 1.");
+		}
+
+		if (to < from) {
+			throw new IllegalArgumentException("End bit < start bit.");
+		}
+
+		int numBits = (to - from) + 1;
+		if (numBits > maxBits) {
+			throw new IllegalArgumentException("Range exceeds type capacity.");
+		}
+		if (to > data.length * 8) {
+			throw new IndexOutOfBoundsException("End of buffer.");
+		}
+
+		if (bigEndian) {
+			return readBigEndian(from, to, numBits);
+		} else {
+			return readLittleEndian(from, to);
+		}
+	}
+
+	/**
+	 * Optimized Byte-Block extraction for Big-Endian.
+	 */
+	private long readBigEndian(int from, int to, int numBits) {
+		int startBit0 = from - 1;
+		int endBit0 = to - 1;
+		int startByte = startBit0 / 8;
+		int endByte = endBit0 / 8;
+
+		long value = 0;
+		for (int i = startByte; i <= endByte; i++) {
+			value = (value << 8) | (data[i] & 0xFFL);
+		}
+
+		int bitsInLastByte = 7 - (endBit0 % 8);
+		value >>>= bitsInLastByte;
+		long mask = (numBits == 64) ? -1L : (1L << numBits) - 1;
+		return value & mask;
+	}
+
+	/**
+	 * Bit-by-bit extraction for Little-Endian to ensure LSB-first accuracy.
+	 */
+	private long readLittleEndian(int from, int to) {
+		long value = 0;
+		for (int i = to - 1; i >= from - 1; i--) {
+			int byteIdx = i / 8;
+			int bitIdxInByte = i % 8; // LSB is bit 0
+			long bit = (data[byteIdx] >> bitIdxInByte) & 1;
+			value = (value << 1) | bit;
+		}
+		return value;
+	}
+}