mirror of
https://github.com/Brandon-Rozek/website.git
synced 2024-11-24 17:16:30 -05:00
123 lines
4.7 KiB
HTML
123 lines
4.7 KiB
HTML
<!DOCTYPE html>
|
|
<html>
|
|
<head>
|
|
<meta charset="utf-8" />
|
|
<meta name="author" content="Fredrik Danielsson, http://lostkeys.se">
|
|
<meta name="viewport" content="width=device-width, initial-scale=1.0">
|
|
<meta name="robots" content="noindex" />
|
|
<title>Brandon Rozek</title>
|
|
<link rel="stylesheet" href="themes/bitsandpieces/styles/main.css" type="text/css" />
|
|
<link rel="stylesheet" href="themes/bitsandpieces/styles/highlightjs-github.css" type="text/css" />
|
|
</head>
|
|
<body>
|
|
|
|
<aside class="main-nav">
|
|
<nav>
|
|
<ul>
|
|
<li class="menuitem ">
|
|
<a href="index.html%3Findex.html" data-shortcut="">
|
|
Home
|
|
</a>
|
|
</li>
|
|
<li class="menuitem ">
|
|
<a href="index.html%3Fcourses.html" data-shortcut="">
|
|
Courses
|
|
</a>
|
|
</li>
|
|
<li class="menuitem ">
|
|
<a href="index.html%3Flabaide.html" data-shortcut="">
|
|
Lab Aide
|
|
</a>
|
|
</li>
|
|
<li class="menuitem ">
|
|
<a href="index.html%3Fpresentations.html" data-shortcut="">
|
|
Presentations
|
|
</a>
|
|
</li>
|
|
<li class="menuitem ">
|
|
<a href="index.html%3Fresearch.html" data-shortcut="">
|
|
Research
|
|
</a>
|
|
</li>
|
|
<li class="menuitem ">
|
|
<a href="index.html%3Ftranscript.html" data-shortcut="">
|
|
Transcript
|
|
</a>
|
|
</li>
|
|
</ul>
|
|
</nav>
|
|
</aside>
|
|
<main class="main-content">
|
|
<article class="article">
|
|
<h1>Lecture on March 22nd</h1>
|
|
<h2>Method Documentation</h2>
|
|
<p>Java has a special way that you can document your methods such that it will create documentation for you if you follow the convention.</p>
|
|
<p>The Java API actually uses this technique to produce its own documentation.</p>
|
|
<p>To create this, indicate a method with special comments that begin with <code>/**</code> and ends with <code>*/</code></p>
|
|
<p>It contains <em>block tags</em> that describe input and output parameters</p>
|
|
<p><code>@param</code> and <code>@return</code></p>
|
|
<h3>Example</h3>
|
|
<pre><code class="language-java">/**
|
|
* @param y an integer to sum
|
|
* @param x an integer to sum
|
|
* @return the sum of x and y
|
|
*/
|
|
public int multiply(int x, int y) {
|
|
return x + y;
|
|
}</code></pre>
|
|
<h2>Passing a Scanner</h2>
|
|
<p>We only want to create one <strong>user input scanner</strong> per program, we also only want one <strong>file input scanner</strong> per program.</p>
|
|
<p>If a method needs a scanner, you can pass the one you already created in as an input parameter.</p>
|
|
<h2>Array as Input Parameter</h2>
|
|
<p>Primitive types (<code>int</code>, <code>char</code>, <code>double</code>, etc.) are passed by value. Modifications made inside a method cannot be seen outside the method.</p>
|
|
<p>Arrays on the other hand, is pass by reference. Changes made to an array inside the method can be seen outside the method.</p>
|
|
<pre><code class="language-java">public static void main(String[] args) {
|
|
int[] nums = {1, 3, 5, 7, 9};
|
|
|
|
timesTwo(nums);
|
|
}
|
|
public static void timesTwo(int[] arr) {
|
|
for (int i = 0; i < arr.length; i++) {
|
|
arr[i] *= 2;
|
|
}
|
|
}</code></pre>
|
|
<p>At the end of the <code>timesTwo</code> method call, the variable <code>nums</code> would have <code>{2, 6, 10, 14, 18}</code></p>
|
|
<h2>Sizes of Arrays</h2>
|
|
<h3>Perfect Size Arrays</h3>
|
|
<p>When we declare an array, Java automatically fills every slot of the array with the type in memory. So if you know that you need exactly 8 slots, then you only ask for 8.</p>
|
|
<h3>Oversize Arrays</h3>
|
|
<p>This is when we don't know how many slots we need. Therefore, we ask for more than we think we'll need. That way we don't go out of bounds.</p>
|
|
<p>If we do this, then we don't know how many elements we have already inserted into the array. Since the length is the number of slots.</p>
|
|
<p>So we can create another variable, which will keep track of the index in where we can add the next element.</p>
|
|
<p>We use oversized arrays when the size of the array is unknown or may change.</p>
|
|
</article>
|
|
</main>
|
|
|
|
<script src="themes/bitsandpieces/scripts/highlight.js"></script>
|
|
<script src="themes/bitsandpieces/scripts/mousetrap.min.js"></script>
|
|
<script type="text/x-mathjax-config">
|
|
MathJax.Hub.Config({
|
|
tex2jax: {
|
|
inlineMath: [ ['$','$'], ["\\(","\\)"] ],
|
|
processEscapes: true
|
|
}
|
|
});
|
|
</script>
|
|
|
|
<script type="text/javascript"
|
|
src="http://cdn.mathjax.org/mathjax/latest/MathJax.js?config=TeX-AMS-MML_HTMLorMML">
|
|
</script>
|
|
<script>
|
|
hljs.initHighlightingOnLoad();
|
|
|
|
document.querySelectorAll('.menuitem a').forEach(function(el) {
|
|
if (el.getAttribute('data-shortcut').length > 0) {
|
|
Mousetrap.bind(el.getAttribute('data-shortcut'), function() {
|
|
location.assign(el.getAttribute('href'));
|
|
});
|
|
}
|
|
});
|
|
</script>
|
|
|
|
</body>
|
|
</html>
|