title: Android regex not acting as I thought it would
body: <p>I'm currently trying to create code to check if the content is Numeric. I found this neat matches command that can handle Regex code but I'm a begginner so It would be awesome if you could explain what I'm doing wrong.</p>
  
  <p>I'm trying to involve E as an exponent and also that it works to type <code>.1</code> as well as <code>0.1</code>. Obviously, I don't want it to be possible to enter more then one punctuation mark and one E.</p>
  
  <p>This is my code:</p>
  
  <pre><code>if (blabla.getText().toString().matches("((-|\\+)?([0-9]|[0-9].|.[0-9])+([0-9]+E)?([0-9]+)?)+")) {
  </code></pre>
  
  <p>At the moment, this code allows you to just enter something like E2 even though for me it looks like it shouldn't return that true because of the ([0-9]|[0-9].|.[0-9])+ in front of that.</p>