public Builder mergeFrom(org.anychat.protobuf.ws.LoginChatProto.GroupMessageS other) {
        if (other == org.anychat.protobuf.ws.LoginChatProto.GroupMessageS.getDefaultInstance()) return this;
        if (!other.getWsOpCode().isEmpty()) {
          wsOpCode_ = other.wsOpCode_;
          onChanged();
        }
        if (messageBuilder_ == null) {
          if (!other.message_.isEmpty()) {
            if (message_.isEmpty()) {
              message_ = other.message_;
              bitField0_ = (bitField0_ & ~0x00000002);
            } else {
              ensureMessageIsMutable();
              message_.addAll(other.message_);
            }
            onChanged();
          }
        } else {
          if (!other.message_.isEmpty()) {
            if (messageBuilder_.isEmpty()) {
              messageBuilder_.dispose();
              messageBuilder_ = null;
              message_ = other.message_;
              bitField0_ = (bitField0_ & ~0x00000002);
              messageBuilder_ = 
                com.google.protobuf.GeneratedMessageV3.alwaysUseFieldBuilders ?
                   getMessageFieldBuilder() : null;
            } else {
              messageBuilder_.addAllMessages(other.message_);
            }
          }
        }
        if (!other.getChatGroupId().isEmpty()) {
          chatGroupId_ = other.chatGroupId_;
          onChanged();
        }
        onChanged();
        return this;
      }
Protobuf type {@code org.anychat.protobuf.ws.GroupMessageS}
AnyChatServer/src/main/java/org/anychat/protobuf/ws/LoginChatProto.java