perf[protocol]: fix string default value

protocol/src/main/java/com/zfoo/protocol/ProtocolManager.java

@@ -65,6 +65,9 @@ public class ProtocolManager {
 
     /**
      * deserialization a packet from the buffer
+     * <p>
+     * byte[] convert to ByteBuf using Unpooled.wrappedBuffer(byte[]) in netty
+     * ByteBuf convert to byte[] using ByteBufUtils.readAllBytes(ByteBuf) in zfoo
      */
     public static Object read(ByteBuf buffer) {
         return protocols[ByteBufUtils.readShort(buffer)].read(buffer);
@@ -81,6 +84,7 @@ public class ProtocolManager {
     public static ProtocolModule moduleByProtocolId(short id) {
         return modules[protocols[id].module()];
     }
+
     public static ProtocolModule moduleByProtocol(Class<?> clazz) {
         return moduleByProtocolId(protocolId(clazz));
     }

protocol/src/main/java/com/zfoo/protocol/serializer/enhance/EnhanceStringSerializer.java

@@ -40,7 +40,7 @@ public class EnhanceStringSerializer implements IEnhanceSerializer {
     @Override
     public String defaultValue(StringBuilder builder, Field field, IFieldRegistration fieldRegistration) {
         var result = "result" + GenerateProtocolFile.index.getAndIncrement();
-        builder.append(StringUtils.format("String {} = \"\"", result));
+        builder.append(StringUtils.format("String {} = \"\";", result));
         return result;
     }