enhancement framework for a class

8/3/2019 Enhancement Framework for a Class

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The post-exit can be used to add or enhance the data flowing from the original method and satisfy the custom business functionality.

Overwrite-exit methods -

Overwrite-exit methods are the enhanced methods which act as a replacement at run time for the original method.

Point to correlate -

If the things are observed closely then it reveals that the 'Pre-exit' and 'Post-exit' methods act like 'Enhancement-point' as in source code

enhancements.

Also, the 'overwrite-exit' method acts like 'Enhancement-section'.

Note: This is the biggest function of the framework which knows what needs to be invoked for that particular 'Exit' method applied

instead or along with the original code.

To understand these powerful techniques here is a practical demonstration of them by means of some basic scenarios.

Note: Here in this scenario the class used is in customer name space ('Z' class).

With respect to the scenario, three methods are used to demonstrate the functionalities of the three enhancement methods (Pre, Post and

Overwrite Exit methods).

Access the class in 'Display' mode which needs to be enhanced.

These are three methods which need to be enhanced,


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Scenario 1: Applying 'pre-exit' for enhancing method 'ZDAVE_METHOD_KNA1'.

Considering the first method 'ZDAVE_METHOD_KNA1', observe the global parameters

Check the source code for the original method,


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This method can be called into an application (say) like a report program which will offer the standard functionality,


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Execute the report, to check out the standard functionality

Test case I -

Observe the outcome,


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Test case II -

Observe the outcome,

Now, we need to enhance this method. To access the enhancement mode,


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As expected it is needed to create an implementation,

Note - It is suggested to create separate implementations for all the three 'Exit method' enhancements.

After selecting the implementation access the enhancement operation option for creating a 'Pre-exit' method enhancement.


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Observe the post-exit created and click on that indication to navigate to enter the custom code.

In this case there are some validations and operations performed in this 'Pre-exit' method,

Activate the 'Pre-exit' method and call the 1st method 'ZDAVE_METHOD_KNA1' into the customer report program

'ZDAVE_KATEGORIEN_ENHC'.

Test the functionality achieved for different test cases,


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As some validation for customer range was carried out, observe the 'Pre-exit' method has triggered

Observe the difference,


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Check the parameters for the method 'ZDAVE_METHOD_KNA2',

Original source code for method 'ZDAVE_METHOD_KNA2',


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After calling the method in the application report program, execute the report

Test case I -

Observe the output,


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Test case II -

Observe the output,

Access the 'Enhance' path (Enhancement Mode) 'Method' 'Enhance'.

Create an Implementation for the method 'ZDAVE_METHOD_KNA2',


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Create a 'Post-exit' method by accessing the path 'Enhancement operations' 'Insert Post-method'

Observe the 'Post-exit' method created and navigate inside to write the enhancement code,


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After the original method does its job the 'Post-exit' method will get invoked and it will allow to enhance the application by adding one more

parameter which will be displayed by the application (here report program), here's the code.


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Now, call the second method 'ZDAVE_METHOD_KNA2' in the report program,


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Execute and enter the desired data,


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Observe the difference,

Scenario 3: Applying 'Overwrite-exit' method to the method 'ZDAVE_METHOD_KNA3',

Check the parameters of the method 'ZDAVE_METHOD_KNA3',

Observe the source code of the original method,


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Call the method in the application report program and test it (Execute)

Test case I -

Output -


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Test case II -

Output -

Now, to replace this functionality with the customer's functionality, we make use of 'Overwrite-exit' method

As usual access the path 'Method' 'Enhance' to enable the enhancement mode.

Create an Implementation,


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Add an 'Overwrite-method' accessing the path,

Observe that the method has been created and follow the indication to code the functionality which will replace the original one,


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Observe the coding logic,


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Activate and call the method in the application report program,


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Now, its time to test the application,

First test case,

Observe that the overwrite-exit method has been triggered,


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To confirm, observe the output,

Second, test case

Again, observe that the overwrite-exit method has been triggered,

Confirm with the output,


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You can refer to the SAP documentation onEnhancing the Components of Classes or Interfaces.
http://help.sap.com/saphelp_nw04s/helpdata/en/86/b83142680d5c33e10000000a155106/content.htmhttp://help.sap.com/saphelp_nw04s/helpdata/en/86/b83142680d5c33e10000000a155106/content.htmhttp://help.sap.com/saphelp_nw04s/helpdata/en/86/b83142680d5c33e10000000a155106/content.htmhttp://help.sap.com/saphelp_nw04s/helpdata/en/86/b83142680d5c33e10000000a155106/content.htm

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