title: Using ArrayList to store variables
body: <p>I'm coding a project to store an array of objects, probably in an arraylist.</p>
  
  <p>So, my object has data elements, getters and setters. I do not have an idea how to access the elements of the object.</p>
  
  <p>For example my object is a book which has the following data elements.</p>
  
  <pre><code>Book
  -&gt;Author
  -&gt;Price
  -&gt;Date
  </code></pre>
  
  <p>If the price of a certain book changes, how do I update the arrayList? Do I need a 2d arrayList? I think indexOf would not work because it is an object? Not really sure. </p>
  
  <p>I'm just a newbie in programming, so I'm not sure if arrayList is the right data structure to use. Thank you very much for reading this, your help will be appreciated. </p>