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
Download the Java Development Kit (JDK)
Download an Integrated Development Environment (IDE)
Create a Java project and class
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 display text within double quotes, we must use an escape sequence for the quotes:
\". Similarly, to display a backslash, we must use \\. We can also use escape sequences such as
\n for a new line character or \t for a tab character.
Comments and Multiline Comments
Comments are text within the code that are ignored by the compiler. They can be used to leave
notes for ourselves or others who may be looking at our code. Single line comments begin with
// and multiline comments are enclosed within /* */.
Tips and Tricks
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
Download the Java Development Kit (JDK)
Download an Integrated Development Environment (IDE)
Create a Java project and class
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 display text within double quotes, we must use an escape sequence for the quotes:
\". Similarly, to display a backslash, we must use \\. We can also use escape sequences such as
\n for a new line character or \t for a tab character.
Comments and Multiline Comments
Comments are text within the code that are ignored by the compiler. They can be used to leave
notes for ourselves or others who may be looking at our code. Single line comments begin with
// and multiline comments are enclosed within /* */.
Tips and Tricks
