All Flashcards
What are the differences between a class and an object?
Class: Blueprint, defines structure and behavior | Object: Instance of a class, actual entity with data and behavior.
What are the differences between primitive types and reference types?
Primitive: Stores actual values directly | Reference: Stores memory address of the value.
What is a class?
A blueprint for creating objects, defining data (instance variables) and behaviors (methods).
What is an object?
A specific instance of a class, holding data and capable of performing actions.
What is a reference type?
A type that stores the memory location of data, rather than the data itself.
What are instance variables?
Variables that belong to a specific object and hold its data.
What is a constructor?
A special method used to create new objects and initialize their instance variables.
Define object instantiation.
The process of creating a new object from a class using the new keyword.
What is the dot operator used for?
Used to access instance variables and methods of an object.
What is a blueprint in the context of Objects and Classes?
A class serves as a blueprint, defining the structure and behavior of objects.
What is the 'new' keyword used for?
The 'new' keyword is used to create a new instance (object) of a class.
What is the purpose of the 'this' keyword?
Refers to the current object within a method or constructor.
Explain the relationship between classes and objects.
A class is a blueprint, and an object is a specific instance created from that blueprint.
Why are objects considered complex entities?
They combine primitive types and other reference types to represent more complex data structures.
What is the significance of objects storing memory locations?
Allows for efficient memory management and sharing of data between different parts of a program.
Why is understanding objects and classes foundational in Java?
They are the building blocks for creating modular, reusable, and maintainable code.
Explain the concept of encapsulation in relation to objects.
Objects encapsulate data (instance variables) and behavior (methods) into a single unit, promoting data hiding and code organization.
What is the main purpose of a constructor?
To initialize the state of an object when it is created.
Explain the concept of object identity.
Each object has a unique identity, even if its attributes have the same values as another object.
What does it mean for a class to 'define characteristics'?
It means the class specifies the data (instance variables) and actions (methods) that its objects will possess.
Why can a class be considered a 'template'?
Because it provides a reusable pattern for creating multiple objects with the same structure and behavior.
Explain the importance of understanding object instantiation for the AP exam.
The AP exam often tests understanding of how objects are created and used, as it's a fundamental concept in object-oriented programming.