ISQI ISAQB Certified Professional for Software Architecture - Foundation Level - CPSA-FL 模擬練習

Explanation:
A) FalseB) FalseC) FalseD) TrueE) TrueF) False
Postel's law, also known as the robustness principle, is a guideline in software engineering that advises to "be conservative in what you do, be liberal in what you accept from others"1. This principle has implications for system design and interaction with external interfaces:
A) Response time of the system is reduced: This is false. Postel's law does not directly relate to the response time of a system1.
B) Implementation effort increases: This is false. Being liberal in what is accepted can actually simplify implementation because the system is designed to handle a wider range of inputs without failure1.
C) Usability of the system is reduced: This is false. Postel's law aims to increase robustness and interoperability, which can enhance usability by making the system more resilient and accommodating1.
D) Robustness of the system is increased: This is true. By being conservative in outputs and liberal in inputs, the system becomes more robust, handling a variety of inputs without error1.
E) The integrity of the data transferred via interfaces is increased: This is true. Accepting a wide range of inputs and adhering strictly to output specifications helps maintain data integrity across different systems1.
F) Availability of the system is reduced due to potentially bad quality of input data: This is false. Postel's law suggests that the system should be designed to handle poor quality input data gracefully, thus maintaining availability1.
Applying Postel's law helps create systems that are more tolerant of input variations and strict in their outputs, contributing to overall system robustness and reliability1.

Explanation:
The statements regarding the design principle 'information hiding' that are true and false are as follows:
* True:
* Adhering to the 'information hiding' principle increases flexibility for modifications (A).
* Information hiding involves deliberately hiding information from callers or consumers of the building block (B).
* In object-oriented development, information hiding is primarily relevant at class level (E).
* False:
* Information hiding makes it harder to distinguish between interface and implementation C.
* Information hiding is a derivative of the approach of incremental refinement along the control flow (D).
The principle of 'information hiding' is a fundamental concept in software engineering that promotes encapsulation and abstraction. Here's an explanation of each statement:
* True Statements:
* (A): Information hiding allows for changes in the implementation without affecting other parts of the system, thus increasing flexibility1.
* (B): The core idea of information hiding is to keep the implementation details away from the users of the component, revealing only what is necessary2.
* (E): In object-oriented programming, information hiding is typically applied at the class level, where internal data and methods are hidden from other classes3.
* False Statements:
* C: Information hiding does not make it harder to distinguish between interface and implementation; rather, it helps to clearly define the interface by hiding the implementation details1.
* (D): Information hiding is not a derivative of incremental refinement along the control flow; it is a separate principle that focuses on hiding the internal complexities of a component4.
Information hiding is crucial for maintaining a clean and modular architecture, where components can be developed, maintained, and replaced independently.
References:
* Stack Overflow discussion on Abstraction vs Information Hiding vs Encapsulation1.
* Wikipedia article on Information Hiding2.
* Kansas State University textbook excerpt on Information Hiding3.
* Techopedia definition of Information Hiding4.

解説: (PassTest メンバーにのみ表示されます)

Explanation:
The performance of a system often competes with its:
* Flexibility (A) - True1
* Memory usage (B) - True1
* On-time completion of the project C - False
* Adaptability (D) - True1
* Usability (E) - True1
* Security (F) - True1
* Testability (G) - True
In system design, performance trade-offs are a critical consideration. Here's an explanation of how each listed aspect competes with system performance:
* Flexibility (A): Systems designed for high performance may be less flexible because they are optimized for specific tasks or conditions1.
* Memory Usage (B): High-performance systems may require more memory to store data and instructions for rapid access, which can be at odds with limited memory resources1.
* On-time Completion of the Project : While performance considerations can impact project timelines, they do not inherently compete with the on-time completion of a project.
* Adaptability (D): Systems that need to perform well under varying conditions may sacrifice adaptability, as they are tightly coupled with their performance optimizations1.
* Usability (E): Sometimes, the pursuit of performance can lead to complex user interfaces or workflows, affecting usability negatively1.
* Security (F): Security measures can introduce additional processing and checks, potentially slowing down system performance1.
* Testability (G): High-performance systems may be harder to test due to their complexity and the need for specialized testing environments or tools1.
These trade-offs highlight the importance of balancing different system attributes to meet the overall goals and constraints of a project.
References:
* CodingDrills article on Trade-Offs in System Design1

Explanation:
A) FalseB) TrueC) True
In a system with a multitude of class dependencies, the following measures can be considered:
A) The dependencies between classes are the responsibility of the developers. No measures are required within the architecture: This is false. While developers do manage day-to-day class dependencies, architectural measures are necessary to address systemic issues in a mature system1.
B) Loosening of direct dependencies between classes through the introduction of interfaces: This is true.
Introducing interfaces can decouple classes and allow for more flexible and maintainable code1.
C) Loosening of direct dependencies between classes through the introduction of factories: This is also true.
Factories can provide a way to create instances of classes without specifying the exact class, thus reducing dependencies1.
These measures align with the iSAQB SOFTWARE ARCHITECTURE - FOUNDATION LEVEL guidelines, which suggest that managing dependencies is crucial for maintaining and extending systems effectively1.