title: Java usage() method
body: <p>Hi Stackoverflow community</p>
  
  <p>I have been trying to find a resource or reference that explains what the usage() method does. Unfortunately the word 'usage' is indexed so often in different contexts that I simply can't find a good resource. Would anybody be able to point me in the right direction?</p>
  
  <pre><code>public static void main(String[] args) {
          if (args.length == 0) {
              usage(); 
          } else if ("parse".equals(args[0])) {
              final String[] parseArgs = new String[args.length - 1];
               etc ....
  </code></pre>
  
  <p>I know that in C getusage() is used to get memory and CPU usage statistics. Is this the same case in Java? Any pointers would be highly appreciated. 
  Mike</p>