Accessing and Modifying Array Elements in Java

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What is the purpose of a constructor in Java?

To access values from an array
To create multiple instances of a class
To declare local variables within a method
To initialize the state of new objects (correct)

What is a common bug associated with constructors?

Indexing, which helps access elements in an array
Abstraction, which hides implementation details
Encapsulation, which separates behavior from state
Shadowing, which re-declares fields as local variables (correct)

In Java, what does encapsulation aim to achieve?

Creating multiple arrays of different types
Hiding implementation details from clients (correct)
Initializing object data to default values
Declaring multiple constructors for a class

What happens if a class in Java has no constructor defined?

Java gives it a default constructor with no parameters setting all fields to 0 (B) Signup and view all the answers

What is the purpose of an array index in Java?

To access specific elements within an array (A) Signup and view all the answers

What does the term 'shadowing' refer to in Java?

Re-declaring fields as local variables within methods (A) Signup and view all the answers

What method is used to set every element of an array to a given value?

fill(array, value) (B) Signup and view all the answers

Which loop type is commonly used with ArrayLists to iterate over elements?

Enhanced For Loop (A) Signup and view all the answers

What is the purpose of the toString method when used with an array?

Return a string representing the array (A) Signup and view all the answers

Which class provides wrapper classes for primitive data types in Java?

Wrappers & Auto-Boxing (B) Signup and view all the answers

In ArrayLists, what method is used to add a new value at a specific location?

.add() (D) Signup and view all the answers

What differentiates Arrays from ArrayLists regarding size flexibility?

Arrays never change in size (A) Signup and view all the answers

What is the main difference between a class and an object?

A class is a template for new types of objects, while an object represents a single instance of the class. (D) Signup and view all the answers

What does each object have its own copy of in terms of fields?

Each object has its own copy of each field inside the class. (A) Signup and view all the answers

What happens if client code tries to access private fields outside the class?

Client code will not compile if it accesses private fields. (C) Signup and view all the answers

What is the purpose of an accessor method in object-oriented programming?

An accessor method allows clients to examine the state of an object. (D) Signup and view all the answers

What is the purpose of a mutator method in OOP?

A mutator method modifies the state of an object. (B) Signup and view all the answers

What defines existence inside each object of a class and gives behavior to each object?

Instance Methods (B) Signup and view all the answers

What is the correct way to access the value of an element in an array named 'a' at a specific index?

a.name[index]; (C) Signup and view all the answers

Which statement about the 'Length Field' in Java arrays is true?

It is accessed using the format a.name.length. (B) Signup and view all the answers

What is the correct syntax for initializing an array named 'results' with double values 3.4 and -0.5?

a.double[] results = {3.4, -0.5}; (D) Signup and view all the answers

What will happen if you attempt to access an index outside the legal range of an array in Java?

It will throw an 'ArrayIndexOutOfBoundsException'. (A) Signup and view all the answers

Which of the following is a limitation when working with arrays in Java?

You can directly compare arrays using '==' operator. (C) Signup and view all the answers

When using a 'For Loop' to access elements in an array, how do you assign a value to each element?

= operator is used on index with 'arrayName[index]'. (A) Signup and view all the answers

What is the main purpose of version control systems in software development?

Identifying and storing different versions of software components (D) Signup and view all the answers

What is a key feature of centralized version control systems?

Using a single master repository to store all versions of software components (B) Signup and view all the answers

How do distributed version control systems differ from centralized VC systems?

Developers create clones of the project repo on their own computers in distributed systems (A) Signup and view all the answers

What happens in a centralized VC system if multiple developers try to work on the same component simultaneously?

The system warns other users that someone else is working on the component (A) Signup and view all the answers

When using a distributed VC system, where are new versions of files maintained before committing changes?

On individual developer's computers in private repositories (C) Signup and view all the answers

What is the key difference between centralized and distributed VC systems in terms of project repository location?

Distributed systems have the main project repo created on a server instead of local computers (A) Signup and view all the answers