Define Session Facade pattern.

Session Facade pattern is all about remove complexities and provide a single interface to user for business calls.

- e.g. for a amount transfer across bank accounts functionality, rather than providing all the mentioned methods in AAAAA, session facade pattern provides a single interface to users as in BBBBB.

AAAAA.
-- checkSourceAcct()
-- checkDestAcct()
-- debitAmountFromSource()
-- CreditAmountToDest()

BBBBB.
-- transferFromSourceToDestAcct()

Advantages
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- User wont have to be dragged to the complexities of the business.
- User will have to handle a single method for calling the business method, rather than a bunch of methods.