title: migrate from Joda time library to Java time(Java 8)
body: <p>I am trying to migrate from Joda time library to Java time (Java 8). 
  I am unable to find equivalent of <code>ISODateTimeFormat.dateOptionalTimeParser()</code> in <code>java.time</code></p>
  
  <p>Joda ISO formatter has nice parsers:</p>
  
  <p><code>ISODateTimeFormat.dateTimeParser()</code> : generic - selects parser based on string parsed.
  Similarly:
  <code>ISODateTimeFormat.dateOptionalTimeParser()</code>.</p>
  
  <p>I am finding it difficult to change Joda time to java.time.
  Can some one guide me? </p>
  
  <p>example: </p>
  
  <pre><code>String dateTimeString = "2015-01-01T12:29:22+00:00"; 
  String dateTimeString2 = "2015-01-01T12:29:22";
  </code></pre>
  
  <p>When I parse this string using joda time then </p>
  
  <pre><code>ISODateTimeFormat.dateTimeParser().withZone("EST")
  </code></pre>
  
  <p>can handle both without as problem. Which is equivalent of this in java time?</p>
  
  <p>Using java 8,  ZonedDateTime with ISO_Zoned_date_time is not able to handle both.</p>