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Showing posts from January, 2019

ADF BC REST service - defaulting with CREATE method

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JDev: 12.2.1.3.0

This is more like an update on my previous article - ADF BC REST - NULL and DEFAULT, where I spoke about the various ways null data can be defaulted via a REST API. However, there was one use case which I had missed - the CREATE method of EntityImpl.

There is an interesting behaviour which may be observed when, instead of  setting a default value declaratively on the entity attribute, we override the CREATE method of the EntityImpl subclass.

When a value is set in the create method, this value takes precedence, irrespective of whether we pass null, some value or don't pass the attribute in the payload at all.

To demonstrate this, I will set a value of 25000 for Salary attribute in the create method.


And I will pass the below payloads:


For all the three payloads, the data gets saved with salary 25000, the value with which it was initialized in the create method, irrespective of the fact that I also have a declarative default value for the Salary entity attribute.


ADF BC REST service - NULL and DEFAULT

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JDev: 12.2.1.3.0 Source: GitHub
This article talks about an interesting difference between passing null and no value for a column in the payload of an ADF BC REST end-point. Now this might seem a bit obvious in the end, but nonetheless, it can be confusing at times.
To demonstrate this problem, I have the following use-case: Set a default value for employee "Salary" during insert or update!
Now your GUI might have some required validation set on this field, and it does not allow the end-user to save the form without a non-zero salary. That is all good. But your QA might have an automation running to check the REST APIs with their own payload. And this is something which needs to be in sync with the UI logic.
To get started, I have my Employee entity object with a default value of 5500 for Salary field.

Case # 1: Payload does not contain Salary attribute

When I submit this payload, I get back an Employee object with the default Salary of 5500, as declaratively set up on the e…

Querying ADF BC REST service - RowFinders and REST Shape

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JDev: 12.2.1.3.0 Source: GitHub
This article talks about querying ADF BC REST services using a RowFinder, and displaying different data sets based on our needs, using REST Shaping.
REST Shaping This is a powerful tool provided by ADF BC to determine the kind of data you can expose to the end user.
Imagine this use-case where we need to display certain attributes of an employee on the front-end application depending on whether we have an anonymous or an authenticated user, while we retain all the features of the view object (View criteria, custom SQL etc). Creating multiple copies of the same VO is certainly not an option.
REST shaping allows you to create metadata on the view object, identified by a unique name, where you can specify which columns may displayed and which all may be hidden.
See examples below, which show two shapes created - AuthView and NoAuthView, each showing different data sets.



Important Note: Each REST instance supports a single REST shape. I did not find any way …