Finished protocol

src/main/java/org/openautonomousconnection/protocol/packets/OACPacket.java

@@ -8,6 +8,9 @@ import org.openautonomousconnection.protocol.versions.v1_0_0.beta.INSResponseSta
 import java.io.DataInputStream;
 import java.io.DataOutputStream;
 import java.io.IOException;
+import java.util.Collections;
+import java.util.LinkedHashMap;
+import java.util.Map;
 import java.util.UUID;
 
 /**
@@ -114,4 +117,50 @@ public abstract class OACPacket extends Packet {
      */
     protected void onResponseCodeRead(DataInputStream inputStream, UUID clientID) {
     }
+
+    /**
+     * Writes a string map in a deterministic way (no Java object serialization).
+     *
+     * @param out output stream
+     * @param map map to write (may be null)
+     * @throws IOException on I/O errors
+     */
+    protected final void writeStringMap(DataOutputStream out, Map<String, String> map) throws IOException {
+        if (map == null || map.isEmpty()) {
+            out.writeInt(0);
+            return;
+        }
+
+        out.writeInt(map.size());
+        for (Map.Entry<String, String> e : map.entrySet()) {
+            // Null keys/values are normalized to empty strings to keep the wire format stable.
+            out.writeUTF((e.getKey() != null) ? e.getKey() : "");
+            out.writeUTF((e.getValue() != null) ? e.getValue() : "");
+        }
+    }
+
+    /**
+     * Reads a string map in a deterministic way (no Java object serialization).
+     *
+     * @param in input stream
+     * @return headers map (never null)
+     * @throws IOException on I/O errors / invalid sizes
+     */
+    protected final Map<String, String> readStringMap(DataInputStream in) throws IOException {
+        int size = in.readInt();
+        if (size < 0) {
+            throw new IOException("Negative map size");
+        }
+        if (size == 0) {
+            return Collections.emptyMap();
+        }
+
+        Map<String, String> map = new LinkedHashMap<>(Math.max(16, size * 2));
+        for (int i = 0; i < size; i++) {
+            String key = in.readUTF();
+            String value = in.readUTF();
+            map.put(key, value);
+        }
+        return map;
+    }
 }