Writing Classes in AP Computer Science A
If a class Graph
has overloaded constructors where one accepts an adjacency matrix and another accepts an edge list representation of a graph, which constructor guarantees immediate readiness for breadth-first search (BFS) without additio...
Graph(List
Graph(String serializedGraph)
Graph(int[][] adjacencyMatrix)
Graph()
Given immutable class named "Timestamp" which uses private final fields for storing data alongside parameterized constructor, what potential drawback might arise from having solely single comprehensive constructor taking numerous parameters...
Having only one constructor makes it easier to understand how to create instances of the class since there are no alternatives.
This approach ensures all required values are set upon object construction avoiding any possible need for additional setter methods or field mutations afterwards.
It complicates creation of instances requiring all data upfront which might not always be available or lead to error-prone code.
Providing just one way to create objects reduces chances of incorrect instantiation by eliminating ambiguity in how to use class correctly making overall design cleaner and more intuitive.
When defining a constructor within a class in Java, what must the constructor's name be?
Different from the class name to avoid confusion.
Preceded by 'new' to indicate object creation.
The same as any method name.
The same as the class name.
How would declaring all constructors as static methods instead affect instantiating an object within that same Java class?
Constructors defined statically would allow direct invocation via classname negatively impacting encapsulation principles.
Declaring constructors statically would lead to objects sharing a single state defined by said static constructor, resembling singleton pattern.
You cannot declare constructors as static methods therefore such declaration would result in compilation failure.
Static constructors could provide global access for object creation bypassing traditional per-instance construction mechanisms.
If a constructor in a class is mistakenly given the same name as the class but with different capitalization, what will most likely be the result when an object of this class is attempted to be instantiated?
The object will be created with default values regardless of any parameters passed.
A compile-time error occurs because Java is case-sensitive and treats it as a method rather than a constructor.
The object will be created successfully because Java ignores capitalization in identifiers.
A run-time exception occurs due to invalid syntax for naming constructors.
When defining two constructors within the same class where one takes two integer parameters and another accepts none, what design concept does this illustrate?
Method overriding allows subclasses to provide specific implementations for methods defined in superclasses.
Polymorphism enables objects to pass more than one IS-A test based on their inheritance hierarchy.
Variable shadowing occurs when local variables or parameters obscure variables from broader scopes.
Constructor overloading allows multiple constructors with different parameter lists within the same class.
How does a constructor with no parameters get classified in Java?
- Empty constructor
Default constructor
- Base constructor
- Nullary constructor

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What is the purpose of an overloaded constructor?
Save memory
Provide flexibility
Hide implementation
Access instance
Assuming a class Matrix
has a constructor that creates an n by m matrix filled with zeros, what is the time complexity of creating an instance if the constructor internally uses nested loops to initialize each element?
In an overloaded set of constructors for Java objects, when should you use 'this()' at the beginning of one constructor?
To override a constructor in superclass.
To create an instance of the class from inside one constructor.
To call another constructor in the same class with matching parameters.
To indicate this constructor has higher priority over other constructors.