JAVA PROGRAMMING FOR BEGINNERS: Master Java Fundamentals and Build Your Own Applications (2023 Crash Course)

JAVA

PROGRAMMING

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TABLE OF CONTENTS

INTRODUCTION ................................................................................ 6

What is the significance of Java? ............................................................. 9

Why is Java used? .................................................................................... 9

CHAPTER 1. .................................................................................... 11

JAVA FUNDAMENTALS ................................................................... 11

Tokens in Java ....................................................................................... 14

Separators ............................................................................................. 16

Comments ............................................................................................. 17

CHAPTER 2 ..................................................................................... 19

VARIABLES ..................................................................................... 19

What exactly are variables?................................................................... 19

Variable types in Java ............................................................................ 20

Choosing a Variable ............................................................................... 22

Primitive types in Java ........................................................................... 23

How to Set Up a Variable....................................................................... 26

CHAPTER 3. .................................................................................... 28

JAVA FUNDAMENTALS ................................................................... 28

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Java Development Kit (JDK) ................................................................... 28

Java SE ................................................................................................... 29

Java EE ................................................................................................... 30

Java ME ................................................................................................. 31

Runtime Environment for Java .............................................................. 32

Virtual Machine in Java ......................................................................... 32

Bytecodes .............................................................................................. 33

CHAPTER 4. .................................................................................... 36

THE JAVA ENVIRONMENT .............................................................. 36

Editors' Writing Programs...................................................................... 36

Eclipse ................................................................................................... 36

IDEA by IntelliJ....................................................................................... 37

Netbeans ............................................................................................... 37

The Benefits of Java ............................................................................... 38

The Drawbacks of Java .......................................................................... 39

CHAPTER 5 ..................................................................................... 40

OBJECTS AND CLASSES ................................................................... 40

Making Objects ..................................................................................... 41

Instance Variables and Methods Access ................................................ 42

Statements of Import ............................................................................ 43

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CHAPTER 6 ..................................................................................... 45

WORKING CODE EXAMPLES ........................................................... 45

Java Projects and Packages (Lesson 1) ................................................... 45

Package naming guidelines: ................................................................... 48

Classes, Superclasses, and Programs (Lesson 2) ..................................... 48

Important Information and More .......................................................... 53

CHAPTER 7 ..................................................................................... 55

OBJECT-ORIENTED PROGRAMMING .............................................. 55

Accessing Methods and Instance Variables ........................................... 59

Statement of Importance ...................................................................... 60

Method of abstraction........................................................................... 63

CHAPTER 8 ..................................................................................... 65

DECISION MAKING AND LOOP CONTROL ....................................... 65

CHAPTER 9 ..................................................................................... 73

ADT, DATA STRUCTURES, AND JAVA COLLECTIONS ARE COVERED . 73

Type of abstract data (ADT) ................................................................... 73

Data-Structure ....................................................................................... 74

Collection Framework in Java ................................................................ 74

Implementation of an ArrayList in JAVA Collections .............................. 75

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ADT Stack Operations ............................................................................ 79

CHAPTER 10 ................................................................................... 83

FILE MANAGEMENT ....................................................................... 83

Text File Reading ................................................................................... 83

BufferedReader ..................................................................................... 84

Java Advanced Topics ............................................................................ 86

CHAPTER 11 ................................................................................... 91

COLLECTIONS ................................................................................. 91

Functional collections ............................................................................ 91

CONCLUSION ............................................................................... 100

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INTRODUCTION

Java is a popular programming language on the Internet and in computer applications. It's a free download solution that lets users access the most recent versions and apply updates. This programming language can be found in the vast majority of today's web applications and computing technologies. Java's scalability makes it suitable for use in a wide variety of applications, including apps for small electronic devices such as cell phones and software solutions for large-scale operations such as data centers. Java's growing popularity can be attributed to its robust functional features and solid security credentials.

Java is a programming language developed by Sun Microsystems, which was later acquired by Oracle Corporation. It is intended to run on any Java-enabled operating system. This is what made the language so popular: the developer only had to write the program once, and it could then run on any operating system without the programmer having to change the code.

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The Java programming language is used to create the majority of modern applications around the world. The Java programming language is used to build the majority of the server-side and business logic components of major applications.

You will learn how to write programs like the one above throughout this book, as well as advanced concepts that will allow you to begin writing complete application programs.

Some of Java's design goals are listed below:

The language is designed to be written only once and run on any operating system.

The language should support several software engineering principles. Portability is an important consideration. This is why Java can run on the Windows, Linux, and macOS operating systems.

Internationalization requires a lot of support.

Java is designed to be used for developing applications for both hosted and embedded systems.

Other design objectives are discussed next:

Type checking is extremely important.

Java is a powerful type of language. Every variable that is defined must be associated with a data type.

You don't need to understand the entire program right now, so let's just look at two lines of code.

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1) int i=5;

In this case, we're defining a variable, which is used to store a value. The amount of data that can be stored is determined by the data type. In this example, I am of the type 'int' or Integer, which is a numeric data value.

Array Bounds Validation

Java will check whether the array has the required number of values at runtime. An exception will be thrown if a value is accessed that is outside the bounds of the array.

You don't need to understand the entire program right now, so let's just look at the following lines of code.

1) int[] array1 = new int[2];

In this case, we're declaring an array, a collection of integer values. The value of ‘2’ means that we can only store two values in the array.

2) array1[0] = 1; array1[1] = 2; array1[2] = 3;

We can see from this code that we are assigning three values to the array. When you run this program, you will receive an error because the array has exceeded its maximum allowable bounds of 8

two. At runtime, you will receive the error shown below. Exception in main thread

At

HelloWorld.main,

java.lang.ArrayIndexOutOfBoundsException: 2 (HelloWorld.java:8) What is the significance of Java?

Next, Java's syntax and features are similar to those of other programming languages such as C and C++. Learning Java will be a breeze if you have any prior programming experience. Even if