This document discusses populators and converters in Hybris. It defines populators as copying data from a source business object to a facade data object (POJO), while converters create new data objects and call populators to populate them. It recommends using Spring configuration to call populators from converters rather than directly in code. The approach is to encapsulate conversions in populators and make data private with getters/setters. An example flow shows how a populator populates a description field to be viewed in the frontend. Configurable populators can invoke specific populators based on data options for performance.

1. Populators & Converters
Sakshi Narang

2. Prerequisite
● Basic knowledge of items.xml (Model concept)
● POJO Concept (Data concept)

3. Agenda
● Clarification about Model and Data(POJO)
● What's Populators and Converters?
● Approach to follow
● Flow of how to make a Populator (One example)
● Configurable Populators & Data Options

4. What's Model?
● Data stored in Hybris database
● 'Model.java' is made
● Done using items.xml

5. POJO?
● What's POJO
– Its a data object class which is used for the frontend.
– Its also used as a DTO.
● Why POJO
– To handle frontend
– To not hit database with every click of the end user
● How to make a POJO?
– Via bean.xml, ant all and its done.(Refer any bean.xml)
– Directly making data.java and

6. Converters
What does converter do?
– It creates new data objects(targets) and calls the
populators to populate these
– One converter can call many populators if the target of
those populators under the same category. Will see later
how list of populators are called in spring.xml using same
target.
– Conversion API is already written. We just need to use
those API in our code and do some configurations in
spring xml. (These configurations we will see in the Flow
Notes).

7. Populators
● It copies data from source business object to the facade
data object(POJO)
● Reverse Populator converts data into model(For Backend)
– Example: Address Form
● Populator converts model into data (For frontend)

8. Approach
● No converters written manually
– Should be Spring configured
– Should use: AbstractConverters as base class
● No populator should be called directly in the code.
– Converters should call them
● All conversion should be done in populators
● Conversion should be well encapsulated and
independent

9. Approach: Meaning of encapsulated
● Encapsulation implements data hiding
– Because data will not be accessed directly to other classes, it will be accessed via
method(getters and setters)
● What's Encapsulation
– Combining data & methods together as a single unit
● Why Encapsulation here
– The fields of the class cannot be made read-only or write-only.
– A class can have total control over what's stored in its fields.
– The users of a class don't know how the class stores its data. The class change the
data types of the field & the users of the class don't need to change any of their code.
● How to achieve this
– Make data declaration private
– Make getters and setters of each data

10. Flow
See Notes to check an example of flow of Populator
showing how description is seen in the frontend.

11. Configurable Populators & Data Options
● Vital for Performance and Bandwidth perspective
● These extend populators interface
● The configurable populators invoke populators that add
data for the given data options.

12. Bookmarks
● https://wiki.hybris.com/display/release5/How+to+Implement+Po
● https://wiki.hybris.com/display/release5/Converters+and+Popul
● https://help.hybris.com/6.1.0/hcd/8b937ff886691014815fcd31ff

13. Q&A