This section provides a documentation of all architectural refactorings (ARs) available in the Context Mapper tool.

Motivation: Why Refactoring?

The provided refactorings ensure that the result is always a correct CML model which compiles without errors. If you perform similar changes manually, you also have to fix errors that occur manually within the Context Map. The ARs ensure that corresponding references and dependencies in other parts of the model are respected and adjusted if necessary.

Architectural Refactoring Categories

The ARs are divided into the following categories:

• Structural Refactorings: Change the structure of the decomposition (impact on Bounded Contexts and/or Aggregates).
• Relationship Refactorings: Just change the type of a relationship on the Context Map, but do not change the structure of the decomposition.

Refactoring Overview

The Context Mapper tool offers you a set of architectural refactorings which can be applied to your CML models. The refactorings shall support you while evolving and improving the architecture of your system.

Structural Refactorings

We currently provide the following structural ARs:

Name	Subject	Description	Input	Output
AR-1: Split Aggregate by Entities	Aggregate	Splits an aggregate which contains multiple entities and produces one aggregate per entity.	1 Aggregate	n Aggregates
AR-2: Split Bounded Context by Features1	Bounded Context	Splits a bounded context by grouping those aggregates together into one bounded context which are used by the same use case(s) and/or user stories (features).	1 Bounded Context	n Bounded Contexts
AR-3: Split Bounded Context by Owner1	Bounded Context	Splits a bounded context by grouping those aggregates together into one bounded context which belong to the same team.	1 Bounded Context	n Bounded Contexts
AR-4: Extract Aggregates by Volatility	Bounded Context	Extracts all aggregates from a bounded context by a given volatility, or likelihood for change (RARELY, NORMAL or OFTEN), and moves them to a separate context.	1 Bounded Context	2 Bounded Contexts
AR-5: Extract Aggregates by Cohesion	Bounded Context	Extracts a set of aggregates which are chosen by certain cohesion criteria and moves them to a separate bounded context.	1 Bounded Context	2 Bounded Contexts
AR-6: Merge Aggregates	Aggregate	Merges two aggregates within a bounded context together to one aggregate.	2 Aggregates	1 Aggregate
AR-7: Merge Bounded Contexts	Bounded Context	Merges two bounded contexts together. The result is one bounded context containing all the aggregates of the two input boundedcontexts.	2 Bounded Contexts	1 Bounded Context
AR-8: Extract Shared Kernel	Shared Kernel relationship	Extracts a new bounded context for the common model parts of the Shared Kernel and establishes two upstream-downstream relationship between the new and the existing Bounded Contexts.	1 Shared Kernel relationship	1 New Bounded Context and 2 new upstream-downstream relationships
AR-9: Suspend Partnership	Partnership relationship	Suspends a Partnership relationship and replaces it with another structure how the two Bounded Context can depend on each other. The AR provides three strategies to suspend the partnership.	1 Partnership relationship	Depends on the selected mode

¹: An aggregate in CML can be used by multiple features (use cases and/or user stories) and is owned by one owner (team).

Relationship Refactorings

The following ARs to change Context Map relationships are currently implemented:

Name	Subject	Description	Input	Output
AR-10: Change Shared Kernel to Partnership	Shared Kernel relationship	Changes the type of a Shared Kernel relationship to a Partnership relationship.	Shared Kernel relationship	Partnership relationship
AR-11: Change Partnership to Shared Kernel	Partnership relationship	Changes the type of a Partnership relationship to a Shared Kernel relationship.	Partnership relationship	Shared Kernel relationship

Examples

You can find input and corresponding output examples for all ARs listed above in our examples repository.

How to apply Architectural Refactorings

Visual Studio Code

In VS Code we suggest the application of Architectural Refactorings via code actions. If your cursor is on a CML object on which an AR can be applied, a light bulb shows up:

In the case illustrated above, the PolicyManagementContext contains Aggregates that are maintained by different teams and Split Bounded Context by Owner (AR-3) can be applied:

By clicking on the light bulb and the AR you want to apply the model will be refactored accordingly.

Eclipse

Architectural refactorings can be applied within the Context Mapper Eclipse plugin by using the context menu in the DSL editor. With a right-click on a bounded context or an aggregate the Context Mapper: Refactor menu entry appears and lists all refactorings which are applicable to the selected elements:

You can also use the Shift-Alt-T keybinding for quick access to the available refactorings (the cursor must be on the object on which you want to start the refactoring).

Note: The context menu only shows ARs for which your selected model element fulfills the preconditions. The preconditions for all ARs are mentioned on the corresponding detail pages linked above.