title: Java NumberFormat ignoring comma in US locale ?
body: <p>I don't understand something in the NumberFormat, in US locale it is suppose to treat comma (",") as a group separator - for thousands.</p>
  
  <p>Why does it ignore commas in incorrect places for this locale ? </p>
  
  <pre><code>NumberFormat format = DecimalFormat.getInstance(Locale.US); 
  System.out.println(format.parse("5,500").longValue()); //5500
  System.out.println(format.parse("550,0").longValue()); //5500
  System.out.println(format.parse("5500,").longValue()); //5500
  </code></pre>
  
  <p>any other ideas how to parse String to Long according to locale (asumming that input of ","
  in incorrect places for the locale should fail) ?</p>