diff --git a/gdProtocol/ProtocolManager.gd b/gdProtocol/ProtocolManager.gd
index b2aab51..0e08f01 100644
--- a/gdProtocol/ProtocolManager.gd
+++ b/gdProtocol/ProtocolManager.gd
@@ -10,8 +10,8 @@ static func getProtocol(protocolId: int):
 	return protocols[protocolId]
 
 static func newInstance(protocolId: int):
-    var protocol = protocols[protocolId]
-    return protocol.new()
+	var protocol = protocols[protocolId]
+	return protocol.new()
 
 static func write(buffer, packet):
 	var protocolId: int = packet.PROTOCOL_ID
@@ -20,10 +20,10 @@ static func write(buffer, packet):
 	protocol.write(buffer, packet)
 
 static func read(buffer):
-    var protocolId = buffer.readShort();
-    var protocol = protocols[protocolId]
-    var packet = protocol.read(buffer);
-    return packet;
+	var protocolId = buffer.readShort();
+	var protocol = protocols[protocolId]
+	var packet = protocol.read(buffer);
+	return packet;
 
 static func initProtocol():
 	protocols[100] = ComplexObject
diff --git a/gdProtocol/buffer/ByteBuffer.gd b/gdProtocol/buffer/ByteBuffer.gd
index f66cbfc..fea48a9 100644
--- a/gdProtocol/buffer/ByteBuffer.gd
+++ b/gdProtocol/buffer/ByteBuffer.gd
@@ -31,6 +31,9 @@ func setReadOffset(readIndex: int) -> void:
 func getReadOffset() -> int:
 	return readOffset
 
+func isReadable() -> bool:
+	return writeOffset > readOffset
+
 # -------------------------------------------------write/read-------------------------------------------------
 func writePoolByteArray(value: PoolByteArray):
 	var length = value.size()
diff --git a/gdProtocol/packet/ComplexObject.gd b/gdProtocol/packet/ComplexObject.gd
index ca35096..9ec6712 100644
--- a/gdProtocol/packet/ComplexObject.gd
+++ b/gdProtocol/packet/ComplexObject.gd
@@ -59,6 +59,9 @@ var ss # java.util.Set<java.util.Set<java.util.List<java.lang.Integer>>>
 var sss # java.util.Set<java.util.Set<com.zfoo.protocol.packet.ObjectA>>
 var ssss # java.util.Set<java.lang.String>
 var sssss # java.util.Set<java.util.Map<java.lang.Integer, java.lang.String>>
+# 如果要修改协议并且兼容老协议，需要加上Compatible注解，按照增加的顺序添加order
+var myCompatible # int
+var myObject # com.zfoo.protocol.packet.ObjectA
 
 const PROTOCOL_ID = 100
 
@@ -202,6 +205,8 @@ static func write(buffer, packet):
 		buffer.writeInt(packet.sssss.size())
 		for element18 in packet.sssss:
 			buffer.writeIntStringMap(element18)
+	buffer.writeInt(packet.myCompatible)
+	buffer.writePacket(packet.myObject, 102)
 
 
 static func read(buffer):
@@ -393,4 +398,12 @@ static func read(buffer):
 			var map120 = buffer.readIntStringMap()
 			result117.append(map120)
 	packet.sssss = result117
+	if (!buffer.isReadable()):
+		return packet
+	var result121 = buffer.readInt()
+	packet.myCompatible = result121
+	if (!buffer.isReadable()):
+		return packet
+	var result122 = buffer.readPacket(102)
+	packet.myObject = result122
 	return packet