Java is known as a strongly typed programming language. In this post I go through the basics of setting up your machine to read, write and run Java programs.

What is Java?

It’s platform with a number of different solutions. It’s most common use case being a back-end programming language to program APIs.

Set Up

Mac

brew install java

java --version

It should look like this:

openjdk 18.0.2 2022-07-19
OpenJDK Runtime Environment Homebrew (build 18.0.2+0)
OpenJDK 64-Bit Server VM Homebrew (build 18.0.2+0, mixed mode, sharing)

If you get the following:

The operation couldn’t be completed. Unable to locate a Java Runtime.
Please visit http://www.java.com for information on installing Java.

Do the following:

sudo ln -sfn /opt/homebrew/opt/openjdk/libexec/openjdk.jdk \
     /Library/Java/JavaVirtualMachines/openjdk.jdk

Java Versions

The current Java version at the time of writing this post is Java 9.

Documentation

https://docs.oracle.com/en/java/

Create Your First Program

mdkir [directory-name]

cd [directory-name]

touch [file-name].java

Open up the Java file in the code editor and insert the following code.

public class [file-name] {
  public static void main(Stringp[] ars) {
    System.out.println("This is my first Java program!")
  }
}

What does this code do?

It should print out, “this is my first Java program!” in the terminal.

Run Your First Program

Save the file and close it. Head over back to the terminal.

javac [file-name].java

java [file-name]

Other Simple Code Examples

public class [file-name] {
  public static void main(Stringp[] ars) {
    System.out.println(1+2)
}

public class [file-name] {
  public static void main(Stringp[] ars) {
    System.out.println("hello" + "world")
  }
}

Part two will look at different variable and data types.