MCS 219 Solved Guess Paper 2026 for Object Oriented Analysis and Design (Master of Computer Applications MCA_NEW)

Sample 1: What is object oriented modelling? List the advantages of object oriented modelling and explain the various stages in object oriented modelling.

Object oriented modelling is an approach in which objects and their characteristics are described without depending on any programming language. The analyst does not need to think about the final implementation language while modelling.

Stages in object oriented modelling

1. System analysis: a problem statement is formulated and the analyst builds a model of real-world situations that a naive user or an expert can follow.
2. System design: the complete architecture is designed and a large system is partitioned into subsystems based on the analysis model.
3. Object design: data structures and algorithms for each class are decided, operations are finalised, access paths are optimised and related classes are packaged into modules.
4. Implementation: classes and relationships are implemented in a chosen language using sound software engineering practice.

Advantages

1. Faster development of the system.
2. Higher quality of the software.
3. Easier maintenance.
4. Reuse of software, designs and frameworks.
5. Lower development risk when integrating complex systems.

Conclusion: OO modelling describes objects and their relationships independent of language and moves through analysis, system design, object design and implementation to deliver reusable, maintainable systems.

Sample 2: What is a dynamic model? Explain the use of a dynamic model. Also explain event, state and transition in the context of a state diagram.

The dynamic model shows the time-dependent behaviour of a system and its objects. Its two main concepts are events, which represent external stimuli, and states, which represent the values of objects.

Use of the dynamic model

1. It matters most in interactive systems, where behaviour depends on the sequence of events over time.
2. It describes control, meaning the sequence of operations that happen in response to external stimuli.
3. It complements the static object model by capturing the parts of a system concerned with time and change.

Event, state and transition

1. Event: an action-oriented occurrence such as a mouse click or applying a brake. It is a one-way transmission of information from one object to another and has no duration.
2. State: a condition during the life of an object. It has a duration and is usually tied to some activity.
3. Transition: the change from one state to another, triggered by an event and drawn as an arrow between two states.

In the full guess paper this answer carries a labelled state diagram of a telephone call (idle, dial tone, dialling, ringing, connected).

Conclusion: the dynamic model captures time-dependent behaviour through events and states, and a state diagram links those states with event-triggered transitions.

Sample 3: What is concurrency? Explain the need for concurrency management. What is synchronisation? Explain its models in UML.

Concurrency is the property that separates an active object from an inactive one, allowing two or more objects to execute at the same time. A single process or task is called a thread of control, and a concurrent system can run many threads in parallel through scheduling.

Need for concurrency management

1. Real systems handle many events at once, often more than a single processor can manage.
2. Synchronisation is needed to avoid deadlock, where threads hold one resource while waiting for another.
3. It also prevents starvation, where a thread never gets the resource it needs.

Synchronisation models in UML

1. Sequential model: the object handles one flow at a time and callers coordinate outside the object.
2. Guarded model: calls to guarded operations are sequenced so only one runs at a time, keeping the object consistent.
3. Concurrent model: several flows run safely inside the object, supported by language features such as the synchronized keyword in Java.

Conclusion: concurrency lets active objects run together, and it must be managed through sequential, guarded or concurrent synchronisation to prevent deadlock and starvation.

Sample 4: Explain how object classes are mapped to database tables. Also explain the use of object IDs and their advantages.

An object identifier (OID) is a unique name for an object; in a database it is a set of integers that uniquely identifies each row in a table.

Mapping object classes to tables

1. Start with the attributes of a class. Each attribute becomes one or more columns in a relational table.
2. Attributes used only for temporary calculations are not stored permanently.
3. Objects may be partitioned horizontally (frequently used objects in one table) or vertically (attributes with different access needs in separate tables) for efficiency.
4. An implicit object ID is added as the primary key, and a candidate key such as StudentID is marked not-null.
5. SQL is then used to create the tables in the database.

Advantages of object IDs

1. They never change the data, so they give a steady way of referring to objects.
2. That stability helps associations, because one change updates many linked records consistently.

One limitation is worth writing too: an RDBMS does not generate object IDs by itself, since it works on attribute values.

Conclusion: classes are mapped by turning attributes into columns, partitioning objects for speed and adding an object ID as the primary key.

Sample 5: What is the need for design documentation? What are the types of documentation? Explain the features of a good design document.

Design documentation is the information that fully describes the design process, covering all interfaces and implementation aspects so the software can be maintained and reused. It forms part of system documentation.

Need for design documentation

1. Software is split into modules handled by many developers, so everyone needs one shared record.
2. Development is iterative, so decisions must be written down as they change.
3. A new version is easier to build when the previous design is documented.
4. Testing against performance criteria and later maintenance both depend on detailed documents.

Types of documentation

1. User documentation.
2. System documentation, which includes design documentation.
3. Project documentation.

Design documents are further grouped into static overview, dynamic overview, class interface description, task interface description, class implementation and task implementation.

Features of a good design document

1. Well organised and clearly structured.
2. Summarised, uniform and reliable.
3. Covers every requirement collected during analysis.
4. Uses more diagrams and less running text.

Conclusion: design documentation records the whole design process, and a good one is structured, complete and pictorial.