Console

Create Working Directory

Let's start by creating a directory with any name you like: e.g. "Examples", "Temp", "Scratch", etc (up to you). We'll call it the working directory

C:
 \---Work
     \---Scratch

Open ZIP file

Open this ZIP file Greeter.zip

Greeter.java
GreeterTester.java

Copy Files from ZIP into Working Directory

Copy "Greeter.java" and "GreeterTester.java" from the ZIP to your working directory.

C:
 \---Work
     \---Scratch
         Greeter.java
         GreeterTester.java

Open Console

Open the console window. Also see opening console. Make sure the current directory in the console is the working directory (where the copied files are located). You can change directories using the "cd" command if needed.

C:\Work\Scratch>

Compile Greeter.java

In the console:

Type the command "javac Greeter.java"
Hit the Enter key

Note: This is how to generally compile -- e.g. "javac Person.java", "javac Ball.java", etc.

C:\Work\Scratch>javac Greeter.java

C:\Work\Scratch>

Compile GreeterTester.java

In the console type the command "javac GreeterTester.java"
Hit the Enter key

C:\Work\Scratch>javac GreeterTester.java

C:\Work\Scratch>

Verify Compiles

In the console type the command "dir" and hit Enter (note: on the MAC/unix the command is "ls")
We should see the compiled file Greeter.class
We should see the compiled file GreeterTester.class

Note that we could also browse this directory in a file browser.

C:\Work\Scratch>1dir
 Volume in drive C is Windows
 Volume Serial Number is E2BE-184D

 Directory of C:\Work\Scratch

01/24/2020  12:02 PM    <DIR>          .
01/24/2020  12:02 PM    <DIR>          ..
01/24/2020  11:59 AM               429 2Greeter.class
02/05/2019  09:29 PM               196 Greeter.java
01/24/2020  12:02 PM               699 3GreeterTester.class
02/05/2019  09:34 PM             1,114 GreeterTester.java
               4 File(s)          2,438 bytes
               2 Dir(s)  379,765,329,920 bytes free

Run GreeterTester.java

In the console type the command "java GreeterTester" and hit the Enter key
The program output

Notes:

We use the command "java" rather than "javac"
We do not include the file extension for this command. We use "GreeterTester" rather than "GreeterTester.java"

C:\Work\Scratch>1java GreeterTester

2GREETINGS to you from a simple Java program!!