How to use escape sequence in java

I have below String

String Tapvalue = Tap8P.concat(last4);

Which I need to add inside below command

String External1 =  "cat /mnt/fs0/config/\Tapvalue/extio0  | grep -A2 External1 | grep configId | awk -F \"[><]\" '{print $3}'";

If you notice in above command i have used \ prior to Tapvalue but it is not working