title: What exactly does String.codePointAt do?
body: <p>Recently I ran into <a href="http://docs.oracle.com/javase/6/docs/api/java/lang/String.html#codePointAt%28int%29">codePointAt</a> method of String in Java. I found also a few other <em>codePoint</em> methods: <code>codePointBefore</code>, <code>codePointCount</code> etc. They definitely have something to do with Unicode but I do not understand it. </p>
  
  <p>Now I wonder when and how one should use <code>codePointAt</code> and similar methods.</p>