Programming Paradigms Midterm Terms | Quizlet

JVM

Java Virtual Machine (JVM) is a virtual machine that enables a computer to run Java programs

JDK

Java Development Toolkit (JDK) is a distribution of Java Technology by Oracle Corporation

compiler

A compiler is a special program that translates a programming language's source code into machine code, bytecode, or another programming language

bytecode

Bytecode is computer object code that an interpreter converts into binary machine code so it can be read by a computer's hardware processor

main

The main function serves as the starting point for program execution

void

Void functions are created and used just like value-returning functions except they do not return a value after the function executes

constructor

A Java constructor is a special method that is used to initialize objects

default constructors

A default constructor is a constructor created by the compiler if we do not define any constructor(s) for a class

import

Java import declares a Java class to be used in the code it's being imported into

primitive types

- Primitive types are the most basic data types available within the Java language

-There are eight primitive types in Java: boolean, byte, char, short, int, long, float, and double

- Boolean is always initialized to false, and the rest are initialized to 0

reference

A reference is an address that indicates where an object's variables and methods are stored

reference type (aka class type)

Reference type variables are objects (such as String and ArrayList) and they are always initialized to null

Object and objects

A java object is a member (also called an instance) of a Java class

class

A class is a user defined blueprint or prototype from which objects are created

casting

Casting is when you assign a value of one primitive data type to another

instance

An instance variable is a variable that is specific to a certain object

inheritance

Inheritance in Java is the method to create a hierarchy between classes by inheriting from other classes

this

The this keyword refers to the current object in a method or constructor

super

The super keyword refers to superclass (parent) objects

static

The static keyword in Java indicates that a particular member is not an instance, but rather part of a type

local variable

A local variable in Java is a variable that's declared within the body of a method

member variable

A member variable (aka instance variable) is declared in a class, but outside a method

class variable

Class variables are similar to member variables but they're declared with the static keyword

scope

Scope is when variables are only accessible inside the region they are created

exceptions

An exception is an event that disrupts the normal flow of the program's instructions

try/catch block

- A try/catch block is the block of code in which exceptions occur

-The try statement allows you to define a block of code to be tested for errors while it is being executed

-The catch statement allows you to define a block of code to be executed if an error occurs in the try block

throw

The throw keyword in Java is used for explicitly throwing a single exception

new

The new keyword is used to create an instance of the class

allocate

Memory allocation in Java refers to the process where the computer programs and services are allocated dedicated to virtual memory spaces

instantiate

Creating an object by using the new keyword is called instantiation

interface

In Java, an interface specifies the behavior of a class by providing an abstract type

implements

The implements keyword is used to implement an interface

declare

Used when you want to declare a variable

initialize

In Java, an initializer is a block of code that has no associated name or data type and is placed outside of any method, constructor, or another block of code

extends

extends keyword is used to extend the functionality of the parent class to the subclass

shadowing

shadowing is the practice of using variables in overlapping scopes with the same name where the variable in low-level scope overrides the variable of high-level scope

polymorphism

polymorphism refers to the ability of a class to provide different implementations of a method, depending on the type of object that is passed to the method

abstract

The abstract keyword is a non-access modifier, used for classes and methods

collections

The Java collections framework provides a set of interfaces and classes to implement various data structures and algorithms

iterators

An Iterator is an object that can be used to loop through collections, like ArrayList and HashSet

ArrayList

An ArrayList class is a resizable array, which is present in the java. util package

public

can be accessed by anything

private

can only be accessed by the class in which it is declared

protected

can be accessed by anything except the world (it is not visible outside the package)

ConncurrentModificationException

The ConcurrentModificationException is used to fail-fast when something being iterated on is modified

RuntimeException

RuntimeException is the superclass of those exceptions that can be thrown during the normal operation of the Java Virtual Machine

NullPointerException

NullPointerException is a runtime exception in Java that occurs when a variable is accessed which is not pointing to any object and refers to nothing or null

overriding

In Java, method overriding occurs when a subclass (child class) has the same method as the parent class

overloading

Method overloading in java is a feature that allows a class to have more than one method with the same name, but with different parameters

model-view-controller architecture

-Model updates the View

-View sends input to the controller

-Controller manipulates the model

-Sometimes the controller updates the view directly

What is encapsulation?

Encapsulation is the bundling of data and the methods that operate on that data within a single unit, often a class in object-oriented programming.

What is a stack?

A stack is a linear data structure that follows the Last In First Out (LIFO) principle, where the last element added is the first one to be removed.

What is a heap?

A heap is a specialized tree-based data structure that satisfies the heap property, where the parent node is either greater than or equal to (max-heap) or less than or equal to (min-heap) its child nodes.

What is the difference between throw and throws?

'throw' is used to explicitly throw an exception in the body of a method, while 'throws' is used in method declarations to specify that a method may throw one or more exceptions.

What is abstraction in programming?

Abstraction is the concept of hiding the complex implementation details and showing only the essential features of an object.

What is the principle of least privilege?

The principle of least privilege states that a user, program, or system should have only the minimum privileges necessary to perform its tasks.

What are shallow copies and deep copies?

Shallow copies create a new object, but do not create copies of nested objects; a deep copy creates a new object and also recursively copies all nested objects.