[Q] In AOSP which class sends ordered broadcast when new SMS recieved topic

I am very new to AOSP and have very little knowledge about it. As per my requirement I would like to add a filter for SMS before it gets broadcast to its receivers. So which class in AOSP is responsible to send the ordered broadcast when a new SMS received by android system.

Question :
In AOSP which class sends ordered broadcast when new SMS recieved with action android.provider.Telephony.SMS_RECEIVED

Thanks in advance.

xda-developers