Requirements

Let's imagine we're building a system for a high-end guitar store that specializes in rare and vintage instruments. The store needs a robust inventory management system to track its collection of guitars, their attributes, and their availability. This isn't just about counting guitars; it's about capturing the unique characteristics that make each instrument special. Think of it as a system that could eventually power a detailed online catalog, providing guitar enthusiasts with the information they crave. The system should be able to efficiently handle a large number of guitars, each with a rich set of properties, and support complex search queries. Because multiple employees might be adding or updating inventory concurrently, we must consider thread safety. # Requirements ## Functional Requirements 1. **Guitar Registration:** The system must allow adding new guitars to the inventory. Each guitar should have the following attributes: * Serial Number (Unique Identifier) * Model * Manufacturer * Year * Wood Type (Body, Neck, Fretboard) * Finish * Number of Frets * Pickups (Type, Configuration) * Current Condition (Excellent, Good, Fair, Poor) * Original Purchase Price * Current Asking Price * Any modifications done to the guitar (e.g., pickup replacement, refretting). Store these as a list of `Modification` objects, with each modification having a description and date. * A history of price changes (date and price). Store these as a list of `PriceChange` objects, with each price change having a date and the new price. 2. **Guitar Search:** The system must allow searching for guitars based on various criteria, including: * Serial Number (Exact match) * Model (Partial match) * Manufacturer (Exact match) * Year (Range) * Wood Type (Any or specific wood types) * Price (Range) * Condition (Specific condition) * Combinations of the above criteria (e.g., find all Fender Stratocasters made between 1960 and 1970 with an asking price between $10,000 and $15,000). 3. **Guitar Information Retrieval:** The system must allow retrieving detailed information about a specific guitar, given its serial number. This should include all the attributes listed in Guitar Registration. 4. **Guitar Updates:** The system must allow updating the information about an existing guitar, including: * Modifying any of the attributes listed in Guitar Registration. * Adding a new modification to the guitar's modification history. * Adding a new price change to the guitar's price change history. 5. **Guitar Deletion:** The system should allow removing a guitar from the inventory, given its serial number. 6. **Inventory Reporting:** The system should provide basic inventory reports, such as: * Total number of guitars in the inventory. * Number of guitars by manufacturer. * Average asking price of guitars by manufacturer. 7. **Data Persistence:** The system needs to store the guitar inventory data. For simplicity, let's use in-memory storage for now, but the design should allow for easy swapping to a persistent storage solution (like a file or database) later. ## Non-Functional Requirements 1. **Thread Safety:** The system must be thread-safe, as multiple employees might be adding, updating, or searching for guitars concurrently. Consider using appropriate synchronization mechanisms to prevent data corruption. 2. **Extensibility:** The system should be easily extensible to support new guitar attributes, search criteria, and reporting features in the future. 3. **Modularity:** The system should be designed in a modular way, with clear separation of concerns between different components. This will make it easier to maintain and modify the code. 4. **Testability:** The system should be designed in a way that makes it easy to write unit tests for different components. This includes using dependency injection and avoiding tight coupling. 5. **Maintainability:** The code should be well-documented and easy to understand. Use meaningful variable names, clear comments, and consistent coding style. 6. **Performance:** While real-time performance is not a primary concern, the search functionality should be reasonably efficient. Consider using appropriate data structures and algorithms to optimize search performance. In-memory operations should be as efficient as possible. ## Core Entities 1. **Guitar:** Represents a guitar in the inventory. It encapsulates all the attributes of a guitar, such as serial number, model, manufacturer, year, wood type, finish, condition, and price. It should be an immutable object once created, with updates handled through a separate mechanism to ensure data consistency and thread safety. 2. **GuitarSpec:** Represents the specifications of a guitar (model, manufacturer, year, wood type, finish, number of frets, pickups). This class is used for searching and filtering guitars based on their specifications. This promotes code reuse and reduces redundancy by grouping common guitar attributes. This can be immutable as well. 3. **Inventory:** Manages the collection of guitars. It provides methods for adding, deleting, searching, and updating guitars in the inventory. It is responsible for ensuring thread safety when accessing and modifying the inventory data. 4. **SearchCriteria:** Represents the criteria used for searching guitars. It encapsulates the search parameters, such as model, manufacturer, year range, wood type, and price range. This allows for flexible and dynamic search queries. The system should allow adding more search criteria easily. 5. **Modification:** Represents a modification made to a guitar. It includes a description of the modification and the date it was made. This provides a history of changes made to the guitar over time. 6. **PriceChange:** Represents a change in the price of a guitar. It includes the new price and the date it was changed. This provides a history of price changes for the guitar.

Design Guitar Inventory System

Requirements

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Functional Requirements

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Non-Functional Requirements

Core Entity Identification

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