Can delegate and strategy patterns coexist ?

Say I have an interface for persistence call that PersistenceInterface.
Now for MySQL I created MySQLPersistenceClass and for DB2 I created one more class DB2PersistenceClass.
Now to proceed with my busines slogic I have a class BusinessLogicHandler class.
BusinessLogicHandler has a class member say persistenceObject of type PersistenceInterface. Now certainly I'm switching the persistence based on the actual implementation so I say Im using STRATEGY pattern here
But for create operation from business layer i.e. BusinessLogicHandler.create directly invokes persistenceObject.create in this case can I say that Im using DELEGATE pattern also
So can I say the set of classes and interface = DELEGATE + STRATEGY ?
Thanks a lot

Can someone please answer this ?yes
can I say the set of classes and interface = DELEGATE + STRATEGY ?yes
Can delegate and strategy patterns coexist ?yes
I'd say it would be odd to use Strategy not as a delegate.

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rhd wrote:
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To be a perfect fit for Strategy pattern, if the abtract class which has the template to solve() is not there and the actual algorithm is down in the FIrstImpl, SecondImpl then its a true strategy?
Design point of view it can be a strategy pattern..
but If you see from the the context and the programs
objective, It is not strategy pattern

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For further info on the Strategy Pattern see here
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Message was edited by: iSchwartz

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Keshav has already outlined required logic, so let me fulfill his answer with a snippet
An Interface
INTERFACE lif_payment.
METHODS pay CHANGING c_val TYPE p.
ENDINTERFACE.
Payment implementations
CLASS lcl_payment_1 DEFINITION.
PUBLIC SECTION.
INTERFACES lif_payment.
ALIASES pay for lif_payment~pay.
ENDCLASS.
CLASS lcl_payment_2 DEFINITION.
PUBLIC SECTION.
INTERFACES lif_payment.
ALIASES pay for lif_payment~pay.
ENDCLASS.
CLASS lcl_payment_1 IMPLEMENTATION.
METHOD pay.
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ENDMETHOD.
ENDCLASS.
CLASS lcl_payment_2 IMPLEMENTATION.
METHOD pay.
    "do something else with c_val i.e.
    c_val = c_val + 10.
ENDMETHOD.
Main class which uses strategy pattern
CLASS lcl_main DEFINITION.
PUBLIC SECTION.
    "during main object creation you pass which payment you want to use for this object
    METHODS constructor IMPORTING ir_payment TYPE REF TO lif_payment.
    "later on you can change this dynamicaly
    METHODS set_payment IMPORTING ir_payment TYPE REF TO lif_payment.
    METHODS show_payment_val.
    METHODS pay.
PRIVATE SECTION.
    DATA payment_value TYPE p.
    "reference to your interface whcih you will be working with
    "polimorphically
    DATA mr_payment TYPE REF TO lif_payment.
ENDCLASS.
CLASS lcl_main IMPLEMENTATION.
METHOD constructor.
    IF ir_payment IS BOUND.
      me->mr_payment = ir_payment.
    ENDIF.
ENDMETHOD.
METHOD set_payment.
    IF ir_payment IS BOUND.
      me->mr_payment = ir_payment.
    ENDIF.
ENDMETHOD.
METHOD show_payment_val.
    WRITE /: 'Payment value is now ', me->payment_value.
ENDMETHOD.
"hide fact that you are using composition to access pay method
METHOD pay.
    mr_payment->pay( CHANGING c_val = payment_value ).
ENDMETHOD.                   ENDCLASS.
Client application
PARAMETERS pa_pay TYPE c. "1 - first payment, 2 - second
DATA gr_main TYPE REF TO lcl_main.
DATA gr_payment TYPE REF TO lif_payment.
START-OF-SELECTION.
"client application (which uses stategy pattern)
CASE pa_pay.
    WHEN 1.
      "create first type of payment
      CREATE OBJECT gr_payment TYPE lcl_payment_1.
    WHEN 2.
      "create second type of payment
      CREATE OBJECT gr_payment TYPE lcl_payment_2.
ENDCASE.
"pass payment type to main object
CREATE OBJECT gr_main
    EXPORTING
      ir_payment = gr_payment.
gr_main->show_payment_val( ).
"now client doesn't know which object it is working with
gr_main->pay( ).
gr_main->show_payment_val( ).
"you can also use set_payment method to set payment type dynamically
"client would see no change
if pa_pay = 1.
    "now create different payment to set it dynamically
    CREATE OBJECT gr_payment TYPE lcl_payment_2.
    gr_main->set_payment( gr_payment ).
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    gr_main->show_payment_val( ).
endif.
Regads
Marcin

Can delegate and strategy patterns coexist ?

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