title: What are Runtime.getRuntime().totalMemory() and freeMemory()?
body: <p>I've been wondering what the exact meaning of  <a href="https://docs.oracle.com/javase/8/docs/api/java/lang/Runtime.html#totalMemory--" rel="noreferrer">Runtime.getRuntime().totalMemory()</a>, <a href="https://docs.oracle.com/javase/8/docs/api/java/lang/Runtime.html#freeMemory--" rel="noreferrer">Runtime.getRuntime().freeMemory()</a>, and <a href="https://docs.oracle.com/javase/8/docs/api/java/lang/Runtime.html#maxMemory--" rel="noreferrer">Runtime.getRuntime().maxMemory()</a> is.</p>
  
  <p>My understanding is, <code>Runtime.getRuntime().totalMemory()</code> returns the total memory my process is using. Is that correct? </p>
  
  <p>How about <code>freeMemory()</code> and <code>maxMemory()</code>?</p>