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11 changes: 11 additions & 0 deletions src/config/sidebarConfig.ts
Original file line number Diff line number Diff line change
Expand Up @@ -65,6 +65,17 @@ export const sidebarSections: Record<string, SidebarSection[]> = {
},
],

// Intro To Java section
'/intro-to-java': [
{
label: 'Intro to Java',
items: [
{ label: 'Stage Overview', slug: 'intro-to-java/stage-overview' },
{ label: 'Java fundamentals', slug: 'intro-to-java/java-fundamentals' },
],
},
],

// Resources section (content lives at /resources but navbar says "Other Resources")
// '/resources': [
// {
Expand Down
18 changes: 12 additions & 6 deletions src/content/docs/index.mdx
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Expand Up @@ -17,6 +17,18 @@ hero:
import HomeCard from '../../components/HomeCard.astro';

<div class="home-cards-grid">
<HomeCard
title="Getting Started"
href="/getting-started/intro-to-prog"
icon="check"
description="Everything you need to know to get started coding."
/>
<HomeCard
title="Intro to Java"
href="/intro-to-java/stage-overview"
icon="book"
description="Goes over the basics of Java that is needed for FRC programming"
/>
<HomeCard
title="Website Feature Guide"
href="/feature-guide/"
Expand All @@ -29,10 +41,4 @@ import HomeCard from '../../components/HomeCard.astro';
icon="wrench"
description="Help contribute! Since FRCSoftware.org is in such an early stage right now, we are in need of contributors."
/>
<HomeCard
title="Getting Started"
href="/getting-started/intro-to-prog"
icon="check"
description="Everything you need to know to get started coding."
/>
</div>
89 changes: 89 additions & 0 deletions src/content/docs/intro-to-java/java-fundamentals.mdx
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@@ -0,0 +1,89 @@
---
title: Java Fundamentals
description: An Intro to print statements and variables
prev: intro-to-java/java-fundamentals
next: false
---
import Aside from '../../../components/Aside.astro';
import ContentFigure from '../../../components/ContentFigure.astro';

## Syntax
As you start programming, you might make a mistake or make a typo. When that happens, your code will have a red line under it. This is because Java has rules called syntax. Syntax is a set of rules that have to be followed so that the computer can understand and run your code. It’s important to pay attention to the syntax!
If your code has a red line under it, first check whether the syntax is correct. This can be done by researching online or by comparing your code with examples.

You can also learn what’s wrong with your code when you put the cursor over the section of the code with the red line and read what the error message is.
Error messages will not tell you exactly what's wrong with your code. If you’re unsure on what the error message means, you can look it up to get additional context.

<ContentFigure src="/java-fundamentals/ErrorExample1.png" />
<ContentFigure src="/java-fundamentals/ErrorExample2.png" />


## Variables
Variables are containers that are used to store information in a program. This could be a variable that holds the temperature or a variable that holds the speed of the motor.

The syntax of a variable is has following:
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is has

small typo here
IMO "is" is the correct word here

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The syntax of a variable is has following:
Variable declarations have the following syntax:

```java
Datatype name = value;
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Might be out of scope for this section (maybe better to specify it in the section on Objects?), but might be worth noting that any Class can be used as a datatype, not just primitives (int, double, etc)

```
Data types refer to the type of value that our variable has. It helps tell our program more information about our variables such as what type of information it holds and how it can be used.
Data types can include numbers, characters or a string of words. Some examples of data types that are commonly used in FRC programming are:
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Some examples of data types

for clarity this might be better as "Some example data types"

* Int: integers or numbers that are positive or negative. Int only allows numbers without decimals. Example: 12
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integers or numbers

small rewrite for clarity: "Integer numbers"

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Int is not a java type; there is int and there is Integer but there is no Int

* Double: Double: numbers that are positive or negative. Unlike int, double allows numbers with or without decimals. Example: 34.1
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Double: Double:

double is repeated twice here

* Boolean: either True or False.
* String: holds a sequence of characters. Example: “Hello World”
* Char: holds a Single character. Example: 'A'
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Single

small capitalization thing

also on the topic of capitalization, are we talking about the primitive types here, or the wrapper objects? This is a bit pedantic for a beginner level course, but int and Int are technically two separate things


The name of your variable can be whatever you want. However, it should be easy to read and make sense to others who may be reading your code.
There are also some rules with variable names. The name of the variable can not include spaces. Instead you can write variables with camel case (frontLeftDrive) and snake case (front_Left_Drive).
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since we program in java, snake_case is generally discouraged (outside constants). Also, what is shown here is snake_Camel_Case

Variable names can not start with a number. However, they can have a number at the end of the name.
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They can have a number at any point in the identifier other than the first character (not just the end).


<Aside type="note">
Java is a case-sensitive programming language! This means that uppercase and lowercase letters are treated as being two different things. For example: MotorID is different from motorID. Even though it’s spelled the same, if your variable name is MotorID then you try to reference it again but spell it as motorID, Java will see the two as different, and your code will get an error.
</Aside>

In Java, semi-colons (;) are similar to a period in a sentence. It is what tells the compiler when a line of code ends. Semi-colons are used commonly in programming and aren’t only for creating variables. We will see more examples of this later in the course.
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In Java, semi-colons (;) are similar to a period in a sentence. It is what tells the compiler when a line of code ends. Semi-colons are used commonly in programming and aren’t only for creating variables. We will see more examples of this later in the course.
In Java, semi-colons (;) are similar to a period in a sentence. It is what tells the compiler when a statement ends. Semi-colons are used commonly in programming and aren’t only for creating variables. We will see more examples of this later in the course.

I think this makes it clearer that if you do something like

int someVariable = 
  someVeryLongMethodNameThatDoesntFitOnTheOriginalLine(argument1, longArgument);

you only need one ;. Statements themselves (as well as expressions) should be covered at some point, perhaps at the end of this lesson.


In FRC, variables can be used to hold information about the robot and its different mechanisms. The example below shows 3 variables that were used for a climber mechanism, CLIMBERID is an integer that holds the motor controller ID number which is 51. UP_POSITION is a double that holds the value -33.5 and DOWN_POSITION is a double that holds the value 0.
```java
int CLIMBERID = 51;
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once again on the case style pedantry, this should for consistency be CLIMBER_ID, as climber and ID are two separate words

double UP_POSITION = -33.5;
double DOWN_POSITION = 0;
```


## Print statements
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I'd add a part here that talks about how print statements aren't really used in FRC, and that we generally use things like networktables/telemetry. It doesn't need to name specifics, just something like:

In FRC, we tend to avoid print statements and instead have other methods of debugging code, which we will talk about in a later section

When programming, it can be useful to display information. This can be helpful for making programs that display information to the user or trying to see what speed that a motor is running.
In Java, we can print information to a terminal using a print statement. A print statement in Java looks like:
```java
System.out.print(“hello!”);
```
What the print statement does is take information inside the parentheses, in the above example, it’s “hello!”, and prints it out to the terminal screen. When using a print statement, the text that we want to print out goes inside the parentheses and is in quotes. However, if we are printing out the value of a variable, then we do not need quotes, as shown below.
```java
int number = 4;
System.out.print(number); // prints out the value 4
```

## Comments
When programming, we use comments to write notes that explain what the code does. This helps make the code more readable for others because if they are unsure of what your code does, they can read your comments. Comments are not run by the compiler, which also means that you can use comments to prevent code from running.
In Java, there are two types of comments. Single-line Comments and Multi-line Comments.
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some clarity things:

  • "Comments are not run by the compiler" could probably be changed to "Comments are ignored by the compiler"
  • "Multi-line" does not need to be capitalized

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In Java, there are two types of comments. Single-line Comments and Multi-line Comments.
In Java, there are two types of comments: single-line comments and multi-line comments.


### Single-line Comments
Single-line comments are // and you add them to the front of your text or line of code. For example, the code below leaves a note of “this prints out Hello World.
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For clarity, I'd probably rewrite this line to something like:

Single line comments begin with // and mark the rest of the line as being a comment. For example, the code below leave the note: "This prints out Hello World."

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Single-line comments are // and you add them to the front of your text or line of code. For example, the code below leaves a note of “this prints out Hello World.
Single-line comments begin with `//` and you add them to the front of your text or line of code. For example, the code below leaves a note of “This prints out Hello World" above the print statement.

```java
// This prints Hello World
System.out.print("Hello World");
```
You will also see comments placed at the end of code like the following
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For clarity pt2: I'd replace "at the end of code" with "at the end of a line"

```java
System.out.print("Hello World"); // This prints Hello World
```
Both examples accomplish the same tasks and there is no difference. If you put your comments above or next to code is up to you and what makes the most sense for your code.
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For clarity pt3: in "If you put your comments above or next to code is up to you", the starting "if" should be replaced with "whether"


### Multi-line Comments
Multi-line Comments start with /* and end with */ The text or code that is in between the two will turn into comments. Multi-line Comments are commonly used when you have many lines of text or need to turn a large amount of code into a comment.
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I'd make sure to add codeblocks `` around any in-line code (`/*`, `*/`). Also make sure to escape * as this is markdown, and *phrase* means italics

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Although in codeblocks you don't need to escape *

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Suggested change
Multi-line Comments start with /* and end with */ The text or code that is in between the two will turn into comments. Multi-line Comments are commonly used when you have many lines of text or need to turn a large amount of code into a comment.
Multi-line Comments start with `/*` and end with `*/` The text or code that is in between the two will turn into comments. Multi-line Comments are commonly used when you have many lines of text or need to turn a large amount of code into a comment.

For example, this is a comment with two lines of text
```java
/* This prints Hello World
This is another line */
System.out.print("Hello World");
```
19 changes: 19 additions & 0 deletions src/content/docs/intro-to-java/stage-overview.mdx
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---
title: Stage Overview
description: An Intro to what Java is and the topics that will be covered in this stage
prev: false
next: intro-to-java/java-fundamentals
---

Learning the basics of Java is the most important step in learning FRC programming because it builds the foundation. In Java, objects are used to create motor
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This paragraph makes little sense, especially because readers at this stage probably have very little understanding of words like object and variable in this context.

controllers that allow a robot to run a motor, variables are used to assign a speed to the motor, and much more. There is a lot to learn when learning Java. However,
FRCSoftware will go over the basics needed to program a robot.

Each section will have different activities and exercises to help build up a good understanding of the basics of Java. If you’re new to programming, it is highly
recommended to go through each step in order. This will help ensure that you don’t miss any important information.

This stage will cover the following topics
* <a href="/intro-to-java/java-fundamentals/"> Java Fundamentals </a>



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