UML:CIM & PIM

• CIM-1: Defining Business processes

The definition and analysis of business processes is to clarify the scope of the system as soon as possible, so as to estimate development costs and time, but not to transform business processes. The system analyst must not misunderstand the purpose of this step. Therefore, when defining and analyzing business processes, system analysts should remember to select the business processes that are relevant to the system.

CIM-1 defines the generation of business processes, mainly with business use case diagrams and briefs

Business use case brief, concise and simple, we mainly use it to record and differentiate business processes.

• CIM-2: Analyzing Business processes

after CIM-1 the business processes that the system will participate in, for each business use case, the system analyst has to start analyzing its workflow and drawing activity Diagram to reach a consensus with the business people. When it comes to CIM-3, it is then possible to define where the system can be assisted and to plan the scope of the system.

• CIM-3: Defining System Scope

After CIM-1 's definition of the business process and CIM-2 's analysis of the business process, it finally entered the grand finale of CIM-3. The CIM-1 and CIM-2 generated files, which are associated with the CIM-3 generated files, are as follows:

Each action in the CIM-2 activity diagram can be a system use case for CIM-3.

Business performers in CIM-1, as well as action principals in CIM-2, are likely to become CIM-3 system performers (systems actors).

• PIM-1: Analyzing the system flow

In the CIM phase, the system analyst takes about 1-2 weeks to generate a preliminary system use case as soon as possible, so that the relevant decision-makers can pick out the system use case for the first development, which is the system scope of the first phase.

Subsequently, the project formally entered the PIM phase, but also formally into the analysis phase, so the system analyst will devote more time, for the first system use cases detailed specifications, as part of the formal requirements of the document, but also as a communication between business personnel and developers of documents.

Therefore, the system analyst in PIM-1 's main work, will for each system use case, analyzes its internal details, and writes the detailed system use case narration (UC Description). UML does not propose standard narrative format for compliance, but the system analyst can find a lot of useful use case narrative format on the network, or read some UML or use case related books, also can find many very special use case narrative format.

• PIM-2: Analyzing Business Rules

The

enterprise controls the whole operation through a set of rules (buisness rules), including the operation of people, processes, systems and concepts, all subject to the business rules. Thus, the importance of business rules, so early from the PIM-1 system use case narration, until the PIM-2 state diagram here and later PIM-3 class diagram, we will require the system analyst must pass these UML diagram, record and present important business rules.

• PIM-3: Defining a static structure

In PIM-3, the system analyst uses the class diagram to express the static structure inside the system. Only with stable and elastic static structure can the system adapt to the change of requirements and quickly support diversified system use cases. After that, the class diagram may be adjusted by the designer's hand and become one of the programmers ' most concerned design drawings. Programmers usually write and organize the source code according to the contents of the class diagram.

In the process of PIM-3, the system analyst looks for an action that takes precedence over the search attribute. Because properties are ubiquitous, especially forms collected from PIM-1, there are many properties that objects must hold. And the search operation is not so straightforward, the system analyst must be more brains to define the operation, so forget the attributes, remember the priority to find operations.

• PIM-4: Defining Operations and methods

In PIM-4, a system analyst can use a sequence diagram to express the interaction between a group of objects in the system when a system use case is completed and executed. Later, the sequence diagram may be adjusted by the designer's hand, and become the programmer's most concern for the design of the second (the other is the class diagram). Programmers usually follow the content of the sequence diagram and write out the source code of the method.

In addition, PIM-1 's system use case narration and PIM-3 class diagram have an indispensable contribution to the PIM-4 sequence diagram. From the PIM-1 system use case narrative, the system analyst can analyze the system flow. In the PIM-3 class diagram, the system analyst defines the static structure inside the system. Then, to the PIM-4 sequence diagram, the system use case and the static structure are combined.

By thinking and expressing the sequence diagram, the system analyst tries to arrange the interaction between the groups of objects generated by the class, so that the group of objects can work together to complete a system use case. Also, in sequence diagrams, the actions that a group of objects interact with can be fed back to the class diagram, defining more actions and attributes, and even discovering other classes and relationships that were not previously discovered.

A system analyst can draw a sequence diagram by referring to the following steps:

1. The performer object that plays the initiator is placed at the left of the sequence diagram, and the performer object that plays the supporter is on the far right of the sequence diagram.
2. For each process step documented in the system use case narrative, determine what data is required for execution and assign the object that owns the data to be responsible for the work.
3. Try to execute the sequence diagram to adjust the process and add parameters to the operation.
4. Feedback the actions and attributes found when plotting the sequence diagram to the class diagram.

• After the CIM and PIM

Since we use the MDA (Model-driven Architecture) development process as a basis for professional division of labor, the work of the system analyst is focused on the CIM and PIM phases, while the PSM and coding phases are entrusted to other designers. The MDA mainly produces UML models, divided into the following three phases:

• The CIM (computation Independent Model) focuses on the system environment and requirements, but does not address the structure and operational details within the system.
• The PIM (Platform Independent Model) focuses on the internal details of the system, but does not involve a specific platform (Platform) to implement the system.
• PSM (Platform specific Model) focuses on the details of the system being implemented on a specific platform. For example, Spring, EJB2, or. NET are a concrete platform.

As a result, the system analyst performs the CIM and PIM steps described above, and after obtaining a high-quality build, the designer will further develop the PSM phase design based on the specific platform, which is coded by the programmer to write code for the specific platform.

UML:CIM & PIM