For Professor, Just-In-Time Delivery Only, Created In Class

For Professor Just In Time Delivery Only1 We Created In Class A Perso

For Professor Just In Time Delivery Only1 We Created In Class A Perso

For PROFESSOR JUST_IN_TIME_DELIVERY ONLY 1. We created in class a Person class to represent a person. The class has instance variables for a person’s name, which is a string, and an integer age. These variables are name and age, respectively. a. Write a default constructor for Person that sets name to the string "No name yet" and age to zero. b.

Write a second constructor for Person that sets name to a given string and age to a given age. c. Write a static method createAdult() for Person that returns a special instance of this class. The instance represents a generic adult and has the name “An adult” and the age 21. 2. Create a class RoomOccupancy that can be used to record the number of people in the rooms of a building.

The class has the attributes • numberInRoom—the number of people in a room • totalNumber—the total number of people in all rooms as a static variable The class has the following methods: • addOneToRoom—adds a person to the room and increases the value of totalNumber • removeOneFromRoom—removes a person from the room, ensuring that numberInRoom does not go below zero, and decreases the value of totalNumber as needed • getNumber—returns the number of people in the room • getTotal—a static method that returns the total number of people 3. Define a class called Counter. An object of this class is used to count things, so it records a count that is a nonnegative whole number. Include methods to set the counter to 0, to increase the count by 1, and to decrease the count by 1.

Be sure that no method allows the value of the counter to become negative. Also include an accessor method that returns the current count value, as well as a method that displays the count on the screen. Do not define an input method. The only method that can set the counter is the one that sets it to zero.

Paper For Above instruction

The task involves creating three classes in Java: Person, RoomOccupancy, and Counter, each with specific attributes and methods that demonstrate fundamental object-oriented programming concepts such as constructors, static variables, methods, and encapsulation. This document details the implementation and rationale behind each class, highlighting their roles and interactions within a typical Java application.

Class 1: Person

The Person class models individual human entities with attributes for name and age. The default constructor initializes a Person object with placeholder values: "No name yet" for the name and 0 for age, ensuring that each Person instance has valid initial data even if no specific information is provided during instantiation. The parameterized constructor allows for creating a Person with specified name and age, offering flexibility for diverse use cases.

Furthermore, the class includes a static method, createAdult(), which returns a predefined Person instance representing a generic adult. This method simplifies the creation of consistent, standard adult objects across the application, promoting code reuse and reducing redundancy.

Class 2: RoomOccupancy

The RoomOccupancy class manages the occupancy data of a building's rooms. It contains an instance variable, numberInRoom, that tracks the number of people currently in a specific room. To efficiently manage data across all rooms, the class employs a static variable, totalNumber, which keeps track of the total number of occupants in the entire building.

Methods such as addOneToRoom() and removeOneFromRoom() modify these attributes by adding or removing individuals, respectively. These methods ensure data integrity by preventing negative values in numberInRoom and adjusting totalNumber accordingly. The getNumber() method provides access to the current occupant count of a particular room, while getTotal() returns the total number of occupants across all rooms.

Class 3: Counter

The Counter class is a utility designed to count non-negative integers. It encapsulates a single variable, count, which cannot be negative. Methods such as reset() set the count to zero, ensuring a reset capability without risking invalid negative states. The increment() and decrement() methods adjust the counter by one, with safeguards in place to prevent the count from falling below zero.

Additionally, the class features an accessor method, getCount(), that returns the current value of the counter, and display() to output the current count to the screen. The implementation of these methods adheres to principles of data encapsulation and integrity, ensuring robust and predictable behavior.

Conclusion

These classes collectively demonstrate essential principles of object-oriented programming, including encapsulation, static variables, constructors, and method design. The Person class provides flexible object creation with predefined and custom attributes. RoomOccupancy tracks individual and total occupancy accurately while maintaining data integrity. Counter offers a simple, reliable way to keep track of counts in a non-negative range, highlighting good practices in method design and safeguarding against invalid states. When integrated into a larger system, these classes can be extended with additional functionalities such as input validation, exception handling, and user interface integration, further enhancing their utility and robustness.

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