add unknown packet object

src/main/java/mc/protocol/UnknownPacket.java

@@ -0,0 +1,25 @@
+package mc.protocol;
+
+import lombok.Data;
+import lombok.ToString;
+
+@Data
+@ToString(exclude = "rawData")
+public class UnknownPacket implements Packet {
+
+    private final State state;
+    private final int id;
+    private final int dataSize;
+    private byte[] rawData;
+
+    @Override
+    public void readSelf(NetInputStream netInputStream) {
+        rawData = new byte[dataSize];
+        netInputStream.readBytes(rawData);
+    }
+
+    @Override
+    public void writeSelf(NetOutputStream netOutputStream) {
+        netOutputStream.writeBytes(rawData);
+    }
+}