• Introduction to Java
➢ In this video, we will cover everything you need to know to get
started with Java programming. Java is one of the top three most
popular programming languages worldwide and is used extensively
by business enterprises, Android apps, and games. Learning Java can
also lead to a high-paying job as a Java developer.
• Why Learn Java?
➢ Java is one of the most popular programming languages worldwide
➢ Java is an extremely flexible language
➢ Java is used extensively by business enterprises, Android apps, and
games
➢ Learning Java can lead to a high-paying job as a Java developer
• Java Basics
➢ Computer languages are on a spectrum between being high level
and low level. Computers only understand binary, which is referred
to as machine code. To create machine code, we write in a format
called source code, which is understandable by humans and
compiles to machine code. When we compile our source code to
machine code, it's machine-specific. Java has an intermediary step
where we can compile our source code to a format called bytecode,
which is cross-platform and can be run on different machines.
• Getting Started with Java
1. Download the Java Development Kit (JDK)
2. Download an Integrated Development Environment (IDE)
3. Create a Java project and class
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, ➢ Java Development Kit (JDK) contains developer tools to help us code
and a Java Runtime Environment (JRE), which contains a library
toolkit and our Java Virtual Machine (JVM). An Integrated
Development Environment (IDE) provides an interface for us to write,
check for errors, compile, and run code.
➢ To create a Java project, we need a unique name and to configure
the JRE. Adding a class to the project is done by selecting the project
folder, going to file, new class, and selecting a unique name. The
class is a collection of related code, and when we compile the source
code to bytecode, we create a new file with the dot class file
extension.
• Introduction to Java Programming
➢ In Java programming, the main method is essential for running the
program. It is contained within the outer set of curly braces of the
class and any code within it will execute starting from the top and
working its way down. To print text to the console window, we can
use
the System.out.print or System.out.println methods.
The latter adds a new line character at the end of the text, while the
former does not. We can also use escape sequences such as \n for
a new line character or \t for a tab character.
• Adding a Main Method
➢ In order to run our code, we must have a main method within the
class. We can generate this method by checking the "public static
void main" checkbox when creating the class. If we accidentally
remove the method, we can simply type it in ourselves: public
static void main(String[] args) { } . Any code within
this method will execute when we run the program.
• Printing to the Console Window
➢ To print text to the console window, we can use
the System.out.print or System.out.println methods. To
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