APCS: AP Computer Science A @sfhs

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====== Hello World Without an IDE ======
They say the only way to teach a fish about water is to remove the fish from the water.  So in the time honored tradition of writing "Hello World!" (whenever you learn a new computer language), lets try.
We need to type the following Java code as a text file.   Java requires that the File name is Capitalized, and ends in ''.java''. 

===== 1. Type the code as a text file =====


=== Linux / MacOS ===

<code bash>
nano First.java
</code>
There is a remote possibility [[https://www.fossmint.com/install-gnu-nano-in-linux/|nano needs to be installed]]
=== DOS / Windows before Win7-64 bit===
''edit First.java''

=== Windows 7-64 bit and later ===
''notepad First.java''
(technically not a command line editor, but they removed that ability for some reason)
====Now (in your respective editor) type:====
<code java>
public class First 
{
	public static void main(String[] args) 
	{
		System.out.println("Hello World!");
	}
}
</code>
===== 2. Compile the Code =====
<code bash>
javac First
</code>
===== 3. Execute the Code =====

<code bash>
java First
</code>

======Summary ======
Doing this once usually ends with the response "There must be a better way!" Now you will appreciate any IDE, and there are many, but we will focus on two: BlueJ and Eclipse.

Recommended reading: Java Methods (4th ed) Chapter 2