Java Programming Fundamentals

• This is a study guide based on a multiple choice test.

Java Basics

• The keyword abstract is used to create an abstract class in Java.
• If the condition inside an IF statement is false, the code inside the ELSE block executes (if present).

Procedural Programming

• In procedural programming, data and functions are separate and not directly related.

Arrays

• A two-dimensional array is a list of arrays.

Loops

• while (false) { System.out.println("Hello"); } will not execute at all because the condition is initially false.

Operators

• The == operator is used to compare two values for equality in Java.

Inheritance

• The synonym of a superclass is a parent class.

Data Types

• The double data type in Java is used to store floating-point numbers with higher precision.

Methods

• In Java, methods must include all of the following except a call to another method.

Instance Variables

• The nonstatic data components of a class often are referred to as the instance variables of that class.

Java Code Execution

• boolean result = (10 > 5) && (5 > 3); will produce true.

Object-Oriented Programming (OOP)

• Iteration is not a main principle of OOP.
• Encapsulation, inheritance and polymorphism are principles of OOP.

Method Calls

• If the method is declared as public static void showResults(double d, int i), a correct method call would be shorResults (12.2, 67);

Floating-Point Variables

• The correct syntax to declare a floating-point variable in Java is float value = 3.14F;

Interfaces

• The keyword implements is used to use interface from a class.

Information Hiding

• The concept of allowing a class's private data to be changed only by a class's own method is known as information hiding.

Boolean Data Type

• Java's boolean data type can store only true or false.

Data Type Selection

• The float data type is best suited for storing a person's height in meters.

OOP Concepts

• Reflection is not a key concept in OOP.

Nested If-Else Statements

• Nested if statements allow multiple conditions to be evaluated sequentially.

Arrays Size

• If you try to store 1000 elements in an array declared as new int[100], a runtime exception will occur.

Java Arithmetic

• After executing the Java code int x = 4; x - = 2; , the value of x will be 2.

Array Initialization

• The correct way to initialize a 1-dimensional array with values 10, 20, and 30 is int arr[] = {10, 20, 30};.

Interfaces in OOP

• The main advantage of using interfaces in OOP is that it allows multiple inheritance in a structured way.

Switch Statements

• switch(5.5) is not a valid condition for a switch statement.