title: Get the Last Modified date of an URL
body: <p>I have three code. This is the first one in which I get the metadata information of any url and in that metadata I have LastModified date also. If I run this class then I get last modified date of url as--</p>
  
  <pre><code>key:- Last-Modified
  value:- 2011-10-21T03:18:28Z
  </code></pre>
  
  <p><strong>First one</strong></p>
  
  <pre><code>public class App {
  
      private static Map&lt;String, String&gt; metaData;    
  
  public static void main(String[] args) {
  
          Tika t = new Tika();
  
          Metadata md = new Metadata();
          URL u = null;
          try {
              u = new URL("http://www.xyz.com/documents/files/xyz-china.pdf");
  
              String content1= t.parseToString(u);
              System.out.println("hello" +content1);
          } catch (MalformedURLException e1) {
              // TODO Auto-generated catch block
              e1.printStackTrace();
          } catch (IOException e) {
              // TODO Auto-generated catch block
              e.printStackTrace();
          } catch (TikaException e) {
              // TODO Auto-generated catch block
              e.printStackTrace();
          }
          try {
              Reader r = t.parse(u.openStream(), md);
          } catch (IOException e) {
              // TODO Auto-generated catch block
              e.printStackTrace();
          }
          try {
          for (String name : md.names()){
              String value = md.get(name);
              System.out.println("key:- " +name);
              System.out.println("value:- " +value);
              //getMetaData().put(name.toLowerCase(), md.get(name));
          }
          }
          catch(Exception e) {
              e.printStackTrace();
          }
  
      }
  
  }
  </code></pre>
  
  <p>But for second example just below this when I run this code and with the same url. I get different Last Modified date of that URL. How to make sure which one is right. As I tried opening that pdf in the browser but instead of getting open in the browser. it is getting open with Adobe PDF on the computer not on the browser so I am not able to check through firebug.</p>
  
  <p><strong>Second Way--</strong></p>
  
  <pre><code>public class LastMod{
    public static void main(String args[]) throws Exception {
      URL url = new URL("http://www.xyz.com/documents/files/xyz-china.pdf");
  
      System.out.println("URL:- " +url);
      URLConnection connection = url.openConnection();
  
  
      System.out.println(connection.getHeaderField("Last-Modified"));
      }
  }
  </code></pre>
  
  <p>For the above one I get Las Mod date as-</p>
  
  <pre><code>Thu, 03 Nov 2011 16:59:41 +0000
  </code></pre>
  
  <p><strong>Third Way--</strong></p>
  
  <pre><code>public class Main{
    public static void main(String args[]) throws Exception {
      URL url = new URL("http://www.xyz.com/documents/files/xyz-china.pdf");
      HttpURLConnection httpCon = (HttpURLConnection) url.openConnection();
  
      long date = httpCon.getLastModified();
      if (date == 0)
        System.out.println("No last-modified information.");
      else
        System.out.println("Last-Modified: " + new Date(date));
  
   }
  }
  </code></pre>
  
  <p>And by third method I get it like this--</p>
  
  <pre><code>Last-Modified: Thu Nov 03 09:59:41 PDT 2011
  </code></pre>
  
  <p>I am confuse which one is right. I think first one is right. Any suggestions will be appreciated..</p>