Google Contacts API version 3.0

<entry gd:etag='contactEtag'>
  <id>http://www.google.com/m8/feeds/contacts/userEmail/base/contactId</id>
  ...
  <gContact:groupMembershipInfo deleted='false'
    href='http://www.google.com/m8/feeds/groups/userEmail/base/groupId'/>
  ...
</entry>

public static void printGroupMembershipInfo(ContactsService myService, URL contactURL)
    throws IOException, ServiceException {
  ContactEntry contact = myService.getEntry(contactURL, ContactEntry.class);

  for (GroupMembershipInfo groupMembershipInfo : contact.getGroupMembershipInfos()) {
    System.out.println("Group's Atom ID: " + groupMembershipInfo.getHref());
  }
}

public static void PrintGroupMembershipInfo(ContactsRequest cr, Uri contactURL)
{
  Contact contact = cr.Retrieve(contactURL);

  foreach (GroupMembership groupMembership in contact.GroupMembership)
  {
    Console.WriteLine("Group's Atom ID: " + groupMembership.HRef);
  }
}

def print_group_membership_info(gd_client, contact_url):
  contact = gd_client.GetContact(contact_url)
  for group_membership_info in contact.group_membership_info:
    print "Group's Atom ID: %s" % group_membership_info.href

<!-- Request -->
DELETE /m8/feeds/contacts/default/full/contactId
If-match: Etag
...
<!-- Response -->
HTTP/1.1 200 OK

public static void deleteContact(ContactsService myService, URL contactURL)
    throws ServiceException, IOException {
  // Retrieving the contact is required in order to get the Etag.
  ContactEntry contact = myService.getEntry(contactURL, ContactEntry.class);

  try {
    contact.delete();
  } catch (PreconditionFailedException e) {
    // Etags mismatch: handle the exception.
  }
}

public static void DeleteContact(ContactsRequest cr, Uri contactURL)
{
  // Retrieving the contact is required in order to get the Etag.
  Contact contact = cr.retrieve<Contact>(contactURL);

  try
  {
    cr.Delete(contact);
  }
  catch (GDataVersionConflictException e)
  {
    // Etags mismatch: handle the exception.
  }
}

def delete_contact(gd_client, contact_url):
  # Retrieving the contact is required in order to get the Etag.
  contact = gd_client.GetContact(contact_url)

  try:
    gd_client.Delete(contact)
  except gdata.client.RequestError, e:
    if e.status == 412:
      # Etags mismatch: handle the exception.
      pass

<!-- Request -->
GET /m8/feeds/photos/media/default/contactId

...
<!-- Response -->
HTTP/1.1 200 OK
Content-Type: image/*
...
[Photo data bytes]

public static void downloadPhoto(ContactsService service, URL contactURL)
    throws ServiceException, IOException {
  ContactEntry entry = service.getEntry(contactURL,  ContactEntry.class);

  Link photoLink = entry.getContactPhotoLink();
  if (photoLink != null) {
    InputStream in = service.getStreamFromLink(photoLink);
    ByteArrayOutputStream out = new ByteArrayOutputStream();
    RandomAccessFile file = new RandomAccessFile("test.jpg", "rw");
    byte[] buffer = new byte[4096];
    while (true) {
      if ((read = in.read(buffer)) != -1) {
        out.write(buffer, 0, read);
      } else {
        break;
      }
    }
    file.write(out.toByteArray());
    file.close();
  }
}

public static void DownloadPhoto(ContactsRequest cr, Uri contactURL)
{
  Contact contact = cr.Retrieve<Contact>(contactURL);

  Stream photoStream = cr.GetPhoto(contact);
  FileStream outStream = File.OpenWrite("test.jpg");
  byte[] buffer = new byte[photoStream.length];

  photoStream.Read(buffer, 0, photoStream.length);
  outStream.Write(buffer, 0, photoStream.length);
  photoStream.Close();
  outStream.Close();
}

def download_photo(gd_client, contact_url):
  contact = gd_client.GetContact(contact_url)

  hosted_image_binary = gd_client.GetPhoto(contact_entry)
  image_file = open('test.jpg', 'wb')
  image_file.write(hosted_image_binary)
  image_file.close()

<!-- Request -->
PUT /m8/feeds/photos/media/default/contactId
If-match: Etag
Content-Type: image/*
...
[Photo data bytes]

...
<!-- Response -->
HTTP/1.1 OK
...

public static void updateContactPhoto(ContactsService myService, URL contactURL, byte[] photoData)
    throws ServiceException, IOException {
  ContactEntry contact = myService.getEntry(contactURL, ContactEntry.class);
  Link photoLink = contact.getContactPhotoLink();
  URL photoUrl = new URL(photoLink.getHref());

  GDataRequest request = myService.createRequest(GDataRequest.RequestType.UPDATE,
      photoUrl, new ContentType("image/jpeg"));

  request.setEtag(photoLink.getEtag());

  OutputStream requestStream = request.getRequestStream();
  requestStream.write(photoData);

  try {
    request.execute();
  } catch (PreconditionFailedException e) {
    // Etags mismatch: handle the exception.
  }
}

public static void UpdateContactPhoto(ContactsRequest cr, Uri contactURL, Stream photoStream)
{
  Contact contact = cr.Retrieve<Contact>(contactURL);

  try
  {
    cr.SetPhoto(contact, photoStream);
  }
  catch (GDataVersionConflictException e)
  {
    // Etags mismatch: handle the exception.
  }
}

def update_contact_photo(gd_client, contact_url, media_object):
  contact = gd_client.GetContact(contact_url)
  try:
    gd_client.ChangePhoto(media_object, contact)
  except gdata.client.RequestError, e:
    if e.status == 412:
      # Etags mismatch: handle the exception.
      pass

<!-- Request -->
DELETE /m8/feeds/photos/media/default/contactId
If-match: Etag

...
<!-- Response -->
HTTP/1.1 OK
...

public static void deleteContactPhoto(ContactsService myService, URL contactURL)
    throws ServiceException, IOException {
  ContactEntry contact = myService.getEntry(contactURL, ContactEntry.class);
  Link photoLink = contact.getContactPhotoLink();
  URL photoUrl = new URL(photoLink.getHref());
  try {
    service.delete(photoUrl, photoLink.getEtag());
  } catch (PreconditionFailedException e) {
    // Etags mismatch: handle the exception.
  }
}

public static void UpdateContactPhoto(ContactsRequest cr, Uri contactURL)
{
  Contact contact = cr.Retrieve<Contact>(contactURL);
  try
  {
    cr.Delete(contact.PhotoUri, contact.PhotoETag);
  }
  catch (GDataVersionConflictException e)
  {
    // Etags mismatch: handle the exception.
  }
}

def update_contact_photo(gd_client, contact_url):
  contact = gd_client.GetContact(contact_url)
  try:
    gd_client.DeletePhoto(contact)
  except gdata.client.RequestError, e:
    if e.status == 412:
      # Etags mismatch: handle the exception.
      pass

<!-- Request -->
GET /m8/feeds/groups/default/full
...
<!-- Response -->
HTTP/1.1 200 OK
Content-Type: application/atom+xml; charset=UTF-8; type=entry
...

<feed xmlns='http://www.w3.org/2005/Atom'
    xmlns:openSearch='http://a9.com/-/spec/opensearch/1.1/'
    xmlns:gContact='http://schemas.google.com/contact/2008'
    xmlns:batch='http://schemas.google.com/gdata/batch'
    xmlns:gd='http://schemas.google.com/g/2005'
    gd:etag='feedEtag'>
  <id>jo@gmail.com</id>
  <updated>2008-12-10T10:44:43.955Z</updated>
  <category scheme='http://schemas.google.com/g/2005#kind'
    term='http://schemas.google.com/contact/2008#group'/>
  <title>Jo March's Contact Groups</title>
  <link rel='alternate' type='text/html'
    href='http://www.google.com/'/>
  <link rel='http://schemas.google.com/g/2005#feed'
    type='application/atom+xml'
    href='https://www.google.com/m8/feeds/groups/userEmail/full'/>
  <link rel='http://schemas.google.com/g/2005#post'
    type='application/atom+xml'
    href='https://www.google.com/m8/feeds/groups/userEmail/full'/>
  <link rel='http://schemas.google.com/g/2005#batch'
    type='application/atom+xml'
    href='https://www.google.com/m8/feeds/groups/userEmail/full/batch'/>
  <link rel='self'
    type='application/atom+xml'
    href='https://www.google.com/m8/feeds/groups/userEmail/full?max-results=25'/>
  <author>
    <name>Jo March</name>
    <email>jo@gmail.com</email>
  </author>
  <generator version='1.0'
    uri='http://www.google.com/m8/feeds'>Contacts</generator>
  <openSearch:totalResults>5</openSearch:totalResults>
  <openSearch:startIndex>1</openSearch:startIndex>
  <openSearch:itemsPerPage>25</openSearch:itemsPerPage>
  <entry>
    <id>http://www.google.com/m8/feeds/groups/userEmail/base/6</id>
    <updated>1970-01-01T00:00:00.000Z</updated>
    <category scheme='http://schemas.google.com/g/2005#kind'
      term='http://schemas.google.com/contact/2008#group'/>
    <title>System Group: My Contacts</title>
    <content>System Group: My Contacts</content>
    <link rel='self' type='application/atom+xml'
      href='https://www.google.com/m8/feeds/groups/userEmail/full/6'/>
    <gContact:systemGroup id='Contacts'/>
  </entry>
  [...Other system groups removed for ease of reading...]
  <entry gd:etag='Etag'>
    <id>http://www.google.com/m8/feeds/groups/userEmail/base/groupId</id>
    <updated>2008-12-10T04:44:37.324Z</updated>
    <category scheme='http://schemas.google.com/g/2005#kind'
      term='http://schemas.google.com/contact/2008#group'/>
    <title>joggers</title>
    <content>joggers</content>
    <link rel='self' type='application/atom+xml'
      href='https://www.google.com/m8/feeds/groups/userEmail/full/groupId'/>
    <link rel='edit' type='application/atom+xml'
      href='https://www.google.com/m8/feeds/groups/userEmail/full/groupId'/>
  </entry>
</feed>

public static void printAllGroups(ContactsService myService)
    throws ServiceException, IOException {
  // Request the feed
  URL feedUrl = new URL("https://www.google.com/m8/feeds/groups/default/full");
  ContactGroupFeed resultFeed = myService.getFeed(feedUrl, ContactGroupFeed.class);

  for (ContactGroupEntry groupEntry : resultFeed.getEntries()) {
    System.out.println("Atom Id: " + groupEntry.getId());
    System.out.println("Group Name: " + groupEntry.getTitle().getPlainText());
    System.out.println("Last Updated: " + groupEntry.getUpdated());

    System.out.println("Extended Properties:");
    for (ExtendedProperty property : groupEntry.getExtendedProperties()) {
      if (property.getValue() != null) {
        System.out.println("  " + property.getName() + "(value) = " +
            property.getValue());
       } else if (property.getXmlBlob() != null) {
        System.out.println("  " + property.getName() + "(xmlBlob) = " +
            property.getXmlBlob().getBlob());
      }
    }
    System.out.println("Self Link: " + groupEntry.getSelfLink().getHref());
    if (!groupEntry.hasSystemGroup()) {
      // System groups do not have an edit link
      System.out.println("Edit Link: " + groupEntry.getEditLink().getHref());
      System.out.println("ETag: " + groupEntry.getEtag());
    }
    if (groupEntry.hasSystemGroup()) {
      System.out.println("System Group Id: " +
          groupEntry.getSystemGroup().getId());
    }
  }
}

public static void PrintAllGroups(ContactsRequest cr)
{
  Feed<Group> fg = cr.GetGroups();

  foreach (Group group in groups.Entries)
  {
    Console.WriteLine("Atom Id: " + group.Id);
    Console.WriteLine("Group Name: " + group.Title);
    Console.WriteLine("Last Updated: " + group.Updated.ToString());

    Console.WriteLine("Extended Properties:");
    foreach (ExtendedProperty property in group.ExtendedProperties)
    {
      Console.WriteLine("  " + property.Name + " = " + property.Value);
    }
    Console.WriteLine("Self Link: " + group.Self);
    if (!string.IsNullOrEmpty(group.SystemGroup))
    {
      // System groups do not have an edit link.
      Console.WriteLine("Edit Link: " + group.GroupEntry.EditUri.Content);
      Console.WriteLine("Etag: " + group.ETag);
    }
    else
    {
      Console.WriteLine("System Group Id: " + group.SystemGroup);
    }
  }
}

def PrintAllGroups(gd_client):
  feed = gd_client.GetGroups()
  for entry in feed.entry:
    print 'Atom Id: %s' % group.id.text
    print 'Group Name: %s' % group.title.text
    print 'Last Updated: %s' % group.updated.text

    print 'Extended Properties:'
    for extended_property in entry.extended_property:
      if extended_property.value:
        value = extended_property.value
      else:
        value = extended_property.GetXmlBlob()
      print '  %s = %s' % (extended_property.name, value)
    print 'Self Link: %s' % entry.GetSelfLink().href
    if not entry.system_group:
      print 'Edit Link: %s' % entry.GetEditLink().href
      print 'ETag: %s' % entry.etag
    else:
      print 'System Group Id: %s' % entry.system_group.id

<!-- Request -->
GET /m8/feeds/groups/default/full
...
<!-- Response -->
HTTP/1.1 200 OK
Content-Type: application/atom+xml; charset=UTF-8; type=entry
...

<feed xmlns='http://www.w3.org/2005/Atom'
    xmlns:openSearch='http://a9.com/-/spec/opensearch/1.1/'
    xmlns:gContact='http://schemas.google.com/contact/2008'
    xmlns:batch='http://schemas.google.com/gdata/batch'
    xmlns:gd='http://schemas.google.com/g/2005'
    gd:etag='feedEtag'>
  <id>jo@gmail.com</id>
  <updated>2008-12-10T10:44:43.955Z</updated>
  <category scheme='http://schemas.google.com/g/2005#kind'
    term='http://schemas.google.com/contact/2008#group'/>
  <title>Jo March's Contact Groups</title>
  <link rel='alternate' type='text/html'
    href='http://www.google.com/'/>
  <link rel='http://schemas.google.com/g/2005#feed'
    type='application/atom+xml'
    href='https://www.google.com/m8/feeds/groups/userEmail/full'/>
  <link rel='http://schemas.google.com/g/2005#post'
    type='application/atom+xml'
    href='https://www.google.com/m8/feeds/groups/userEmail/full'/>
  <link rel='http://schemas.google.com/g/2005#batch'
    type='application/atom+xml'
    href='https://www.google.com/m8/feeds/groups/userEmail/full/batch'/>
  <link rel='self'
    type='application/atom+xml'
    href='https://www.google.com/m8/feeds/groups/userEmail/full?max-results=25'/>
  <author>
    <name>Jo March</name>
    <email>jo@gmail.com</email>
  </author>
  <generator version='1.0'
    uri='http://www.google.com/m8/feeds'>Contacts</generator>
  <openSearch:totalResults>5</openSearch:totalResults>
  <openSearch:startIndex>1</openSearch:startIndex>
  <openSearch:itemsPerPage>25</openSearch:itemsPerPage>
  <entry>
    <id>http://www.google.com/m8/feeds/groups/userEmail/base/6</id>
    <updated>1970-01-01T00:00:00.000Z</updated>
    <category scheme='http://schemas.google.com/g/2005#kind'
      term='http://schemas.google.com/contact/2008#group'/>
    <title>System Group: My Contacts</title>
    <content>System Group: My Contacts</content>
    <link rel='self' type='application/atom+xml'
      href='https://www.google.com/m8/feeds/groups/userEmail/full/6'/>
    <gContact:systemGroup id='Contacts'/>
  </entry>
  [...Other system groups removed for ease of reading...]
  <entry gd:etag='Etag'>
    <id>http://www.google.com/m8/feeds/groups/userEmail/base/groupId</id>
    <updated>2008-12-10T04:44:37.324Z</updated>
    <category scheme='http://schemas.google.com/g/2005#kind'
      term='http://schemas.google.com/contact/2008#group'/>
    <title>joggers</title>
    <content>joggers</content>
    <link rel='self' type='application/atom+xml'
      href='https://www.google.com/m8/feeds/groups/userEmail/full/groupId'/>
    <link rel='edit' type='application/atom+xml'
      href='https://www.google.com/m8/feeds/groups/userEmail/full/groupId'/>
  </entry>
</feed>

public static void printDateMinQueryResults(
    ContactsService myService, DateTime startTime) throws ServiceException, IOException {
  // Create query and submit a request
  URL feedUrl = new URL("https://www.google.com/m8/feeds/groups/default/full");
  Query myQuery = new Query(feedUrl);
  myQuery.setUpdatedMin(startTime);
  ContactGroupFeed resultFeed = myService.query(myQuery, ContactGroupFeed.class);

  // Print the results
  for (ContactGroupEntry entry : resultFeed.getEntries()) {
    System.out.println(entry.getTitle().getPlainText());
    System.out.println("Updated on: " + entry.getUpdated().toStringRfc822());
  }
}

public static void PrintDateMinQueryResults(ContactsRequest cr, DateTime startTime)
{
  GroupsQuery query = new GroupsQuery(GroupsQuery.CreateGroupUri("default"));
  query.StartDate = startTime;
  Feed<Group> feed = cr.Get(query);

  foreach (Group group in feed.Entries)
  {
    Console.WriteLine(group.Title);
    Console.WriteLine("Updated on: " + group.Updated.ToString());
  }
}

def print_date_min_query_results(gd_client, start_time):
  query = gdata.service.Query(feed='/m8/feeds/groups/default/full')
  query.updated_min = start_time
  feed = gd_client.GetGroups(q=query)

  for entry in feed.entry:
    print entry.title.text
    print 'Updated on: %s' % entry.updated.text

<!-- Request -->
GET /m8/feeds/groups/default/full/groupID
...
<!-- Response -->
HTTP/1.1 200 OK
Content-Type: application/atom+xml; charset=UTF-8; type=entry
...

<entry xmlns='http://www.w3.org/2005/Atom'
    gd:etag='ETAG'>
  <id>http://www.google.com/m8/feeds/groups/userEmail/base/groupID</id>
  <updated>2008-12-10T04:44:37.324Z</updated>
  <category scheme='http://schemas.google.com/g/2005#kind'
    term='http://schemas.google.com/contact/2008#group'/>
  <title>joggers</title>
  <content>joggers</content>
  <link rel='self' type='application/atom+xml'
    href='https://www.google.com/m8/feeds/groups/userEmail/full/groupID'/>
  <link rel='edit' type='application/atom+xml'
    href='https://www.google.com/m8/feeds/groups/userEmail/full/groupID'/>
</entry>

public static ContactGroupEntry retrieveContactGroup(ContactsService myService)
    throws ServiceException, IOException {
  ContactGroupEntry group =
      myService.getEntry(new URL("https://www.google.com/m8/feeds/groups/default/full/groupId"),
          ContactGroupEntry.class);

  // Do something with the contact group.
  return group;
}

public static Group retrieveContactGroup(ContactsRequest cr)
{
  Group group = cr.Retrieve<Group>("https://www.google.com/m8/feeds/groups/default/full/groupId");

  // Do something with the contact group.
  return group;
}

def retrieve_contact_group(gd_client):
  group = gd_client.GetGroup('https://www.google.com/m8/feeds/groups/default/full/groupId')

  # Do something with the contact group.
  return group

<!-- Request -->
POST /m8/feeds/groups/default/full
...

<atom:entry xmlns:gd="http://schemas.google.com/g/2005">
  <atom:category scheme="http://schemas.google.com/g/2005#kind"
    term="http://schemas.google.com/contact/2008#group"/>
  <atom:title type="text">Salsa group</atom:title>
  <gd:extendedProperty name="more info about the group">
    <info>Nice people.</info>
  </gd:extendedProperty>
</atom:entry>
...
<!-- Response -->
HTTP/1.1 201 Created
Content-Type: application/atom+xml; charset=UTF-8; type=entry
...

<entry xmlns='http://www.w3.org/2005/Atom'
    gd:etag='ETAG'>
  <id>http://www.google.com/m8/feeds/groups/userEmail/base/groupID</id>
  <updated>2008-12-10T04:44:37.324Z</updated>
  <category scheme='http://schemas.google.com/g/2005#kind'
    term='http://schemas.google.com/contact/2008#group'/>
  <atom:title type="text">Salsa group</atom:title>
  <gd:extendedProperty name="more info about the group">
    <info>Nice people.</info>
  </gd:extendedProperty>
  <link rel='self' type='application/atom+xml'
    href='https://www.google.com/m8/feeds/groups/userEmail/full/groupID'/>
  <link rel='edit' type='application/atom+xml'
    href='https://www.google.com/m8/feeds/groups/userEmail/full/groupID'/>
</entry>

public static ContactGroupEntry createContactGroup(ContactsService service)
    throws ServiceException, IOException {
  // Create the entry to insert
  ContactGroupEntry newGroup = new ContactGroupEntry();
  newGroup.setTitle(new PlainTextConstruct("Salsa group"));

  ExtendedProperty additionalInfo = new ExtendedProperty();
  additionalInfo.setName("more info about the group");
  additionalInfo.setValue("Nice people.");
  newGroup.addExtendedProperty(additionalInfo);

  // Ask the service to insert the new entry
  URL postUrl = new URL("https://www.google.com/m8/feeds/groups/default/full");
  ContactGroupEntry createdGroup = service.insert(postUrl, newGroup);

  System.out.println("Contact group's Atom Id: " + group.getId());
  return createdGroup;
}

public static Group createContactGroup(ContactsRequest cr)
{
  Group newGroup = new Group();
  newGroup.Title = "Salsa group";

  newGroup.ExtendedProperties.Add(new ExtendedProperty()
      {
        Name = "more info about the group",
        Value = "Nice people.",
      });
  Group createdGroup = cr.Insert(new Uri("https://www.google.com/m8/feeds/groups/default/full"),
      newGroup);

  Console.WriteLine("Contact group's Atom Id: " + createdGroup.Id);
  return createdGroup;
}

def create_contact_group(gd_client):
  new_group = gdata.contacts.data.GroupEntry(title=atom.data.Title(text='Salsa group'))
  new_group.extended_properties.append(
      gdata.data.ExtendedProperty(name='more info about the group', value='Nice people.'))

  created_group = gd_client.CreateGroup(new_group)
  print "Contact group's Atom Id: %s" % created_group.id.text
  return created_group

<!-- Request -->
 POST /m8/feeds/groups/default/full/groupID
  If-Match: Etag
  ...
  
  <entry xmlns:gd="http://schemas.google.com/g/2005"
      gd:etag="Etag">
    <category scheme="http://schemas.google.com/g/2005#kind"
      term="http://schemas.google.com/g/2005#group"/>
    <id>http://www.google.com/feeds/groups/userEmail/base/groupId</id>
    <published>2005-01-18T21:00:00Z</published>
    <updated>2006-01-01T00:00:00Z</updated>
    <title type="text">Salsa friends</title>
    <content type="text">Friends from Salsa class</content>
    <link rel='self' type='application/atom+xml'
      href='https://www.google.com/m8/feeds/groups/userEmail/full/groupId'/>
    <link rel='edit' type='application/atom+xml'
      href='https://www.google.com/m8/feeds/groups/userEmail/full/groupId'/>
    <gd:extendedProperty name="more info about the group">
      <info>Very nice people.</info>
    </gd:extendedProperty>
  </entry>
...
<!-- Response -->
  HTTP/1.1 200 OK
  Content-Type: application/atom+xml; charset=UTF-8; type=entry
  ...
  
  <entry xmlns:gd="http://schemas.google.com/g/2005"
      gd:etag="newEtag">
    <category scheme="http://schemas.google.com/g/2005#kind"
      term="http://schemas.google.com/g/2005#group"/>
    <id>http://www.google.com/feeds/groups/userEmail/base/groupId</id>
    <published>2005-01-18T21:00:00Z</published>
    <updated>2011-05-11T00:00:00Z</updated>
    <title type="text">Salsa friends</title>
    <content type="text">Friends from Salsa class</content>
    <link rel='self' type='application/atom+xml'
      href='https://www.google.com/m8/feeds/groups/userEmail/full/groupId'/>
    <link rel='edit' type='application/atom+xml'
      href='https://www.google.com/m8/feeds/groups/userEmail/full/groupId'/>
    <gd:extendedProperty name="more info about the group">
      <info>Very nice people.</info>
    </gd:extendedProperty>
  </entry>

public static ContactGroupEntry updateContactGrpup(ContactsService myService, URL contactGroupURL)
    throws ServiceException, IOException {
  ContactGroupEntry group = myService.getEntry(contactGroupURL, ContactGroupEntry.class);

  group.setTitle(new PlainTextConstruct("Salsa Friends"));
  group.setContent(new PlainTextconstruct("Friends from Salsa class"));
  URL editUrl = new URL(entryToUpdate.getEditLink().getHref());

  try {
    ContactGroupEntry updatedGroup = myService.update(editUrl, entryToUpdate);
    System.out.println("Updated: " + updatedGroup.getUpdated().toString());
    return updatedGroup;
  } catch (PreconditionFailedException e) {
    // Etags mismatch: handle the exception.
  }
  return null;
}

public static Group UpdateContactGroup(ContactsRequest cr, Uri contactGroupUrl)
{
  Group group = cr.Retrieve<Group>(contactGroupUri);

  group.Title = "Salsa Friends";
  group.Content = "Friends from Salsa class";

  try
  {
    Group updatedGroup = cr.Update(group);
    Console.WriteLine("Updated: " + updatedGroup.Updated.ToString());
    return updatedGroup;
  }
  catch (GDataVersionConflictException e)
  {
    // Etags mismatch: handle the exception.
  }
  return null;
}

def create_contact_group(gd_client):
  new_group = gdata.contacts.data.GroupEntry(title=atom.data.Title(text='Salsa group'))
  new_group.extended_properties.append(
      gdata.data.ExtendedProperty(name='more info about the group', value='Nice people.'))

  created_group = gd_client.CreateGroup(new_group)
  print "Contact group's Atom Id: %s" % created_group.id.text
  return created_group

<!-- Request -->
DELETE /m8/feeds/groups/default/full/groupID
If-Match: Etag
...
<!-- Response -->
HTTP/1.1 200 OK
...

public static void deleteContactGroup(ContactsService myService, URL contactGroupURL)
    throws ServiceException, IOException {
  // Retrieving the contact group is required in order to get the Etag.
  ContactGroupEntry group = myService.getEntry(contactGroupURL, ContactGroupEntry.class);

  try {
    group.delete();
  } catch (PreconditionFailedException e) {
    // Etags mismatch: handle the exception.
  }
}

public static void DeleteContactGroup(ContactsRequest cr, Uri contactGroupURL)
{
  // Retrieving the contact group is required in order to get the Etag.
  Group group = cr.Retrieve<Group>(contactGroupURL);

  try
  {
    cr.Delete(group);
  }
  catch (GDataVersionConflictException e)
  {
    // Etags mismatch: handle the exception.
  }
}

def delete_contact_group(gd_client, contact_group_url):
  # Retrieving the contact group is required in order to get the Etag.
  group = gd_client.GetGroup(contact_group_url)

  try:
    gd_client.Delete(group)
  except gdata.client.RequestError, e:
    if e.status == 412:
      # Etags mismatch: handle the exception.
      pass

<!-- Request -->
POST /m8/feeds/contacts/default/private/full/batch
...

<?xml version='1.0' encoding='UTF-8'?>
<feed xmlns='http://www.w3.org/2005/Atom'
      xmlns:gContact='http://schemas.google.com/contact/2008'
      xmlns:gd='http://schemas.google.com/g/2005'
      xmlns:batch='http://schemas.google.com/gdata/batch'>
  <entry>
    <batch:id>retrieve</batch:id>
    <batch:operation type='query'/>
    <id>https://www.google.com/m8/feeds/contacts/default/full/retrieveContactId</id>
  </entry>
  <entry>
    <batch:id>create</batch:id>
    <batch:operation type='insert'/>
    <category scheme='http://schemas.google.com/g/2005#kind' term='http://schemas.google.com/g/2008#contact'/>
    <gd:name>
      <gd:fullName>Elizabeth Bennet</gd:fullName>
      <gd:givenName>Elizabeth</gd:givenName>
      <gd:familyName>Bennet</gd:familyName>
    </gd:name>
    <gd:email rel='http://schemas.google.com/g/2005#home' address='liz@gmail.com' primary='true'/>
  </entry>
  <entry gd:etag='updateContactEtag'>
    <batch:id>update</batch:id>
    <batch:operation type='update'/>
    <id>http://www.google.com/m8/feeds/contacts/userEmail/base/updateContactId</id>
    <updated>2008-02-28T18:47:02.303Z</updated>
    <category scheme='http://schemas.google.com/g/2005#kind'
      term='http://schemas.google.com/contact/2008#contact'/>
    <gd:name>
      <gd:givenName>New</gd:givenName>
      <gd:familyName>Name</gd:familyName>
      <gd:fullName>New Name</gd:fullName>
    </gd:name>
    <content type='text'>Notes</content>
    <link rel='http://schemas.google.com/contacts/2008/rel#photo' type='image/*'
      href='https://www.google.com/m8/feeds/photos/media/userEmail/updateContactId'/>
    <link rel='self' type='application/atom+xml'
      href='https://www.google.com/m8/feeds/contacts/userEmail/full/updateContactId'/>
    <link rel='edit' type='application/atom+xml'
      href='https://www.google.com/m8/feeds/contacts/userEmail/full/updateContactId'/>
    <gd:phoneNumber rel='http://schemas.google.com/g/2005#other'
      primary='true'>456-123-2133</gd:phoneNumber>
    <gd:extendedProperty name='pet' value='hamster'/>
    <gContact:groupMembershipInfo deleted='false'
      href='http://www.google.com/m8/feeds/groups/userEmail/base/groupId'/>
  </entry>
  <entry gd:etag='deleteContactEtag'>
    <batch:id>delete</batch:id>
    <batch:operation type='delete'/>
    <id>https://www.google.com/m8/feeds/contacts/default/full/deleteContactId</id>
  </entry>
</feed>
<!-- Response -->
HTTP/1.1 200 OK
Content-Type: application/atom+xml;
...

<?xml version='1.0' encoding='UTF-8'?>
<feed xmlns='http://www.w3.org/2005/Atom'
      xmlns:gContact='http://schemas.google.com/contact/2008'
      xmlns:gd='http://schemas.google.com/g/2005'
      xmlns:batch='http://schemas.google.com/gdata/batch'>
  <entry gd:etag='retrieveContactEtag'>
    <batch:id>retrieve</batch:id>
    <batch:operation type='query'/>
    <batch:status code='200' reason='Success'/>
    <id>
      http://www.google.com/m8/feeds/contacts/userEmail/base/retrieveContactId
    </id>
    <updated>2008-12-10T04:45:03.331Z</updated>
    <app:edited xmlns:app='http://www.w3.org/2007/app'>2008-12-10T04:45:03.331Z</app:edited>
    <category scheme='http://schemas.google.com/g/2005#kind'
      term='http://schemas.google.com/contact/2008#contact'/>
    <title>Fitzwilliam Darcy</title>
    <gd:name>
      <gd:fullName>Fitzwilliam Darcy</gd:fullName>
    </gd:name>
    <link rel='http://schemas.google.com/contacts/2008/rel#photo' type='image/*'
      href='https://www.google.com/m8/feeds/photos/media/userEmail/retrieveContactId'
      gd:etag='photoEtag'/>
    <link rel='self' type='application/atom+xml'
      href='https://www.google.com/m8/feeds/contacts/userEmail/full/retrieveContactId'/>
    <link rel='edit' type='application/atom+xml'
      href='https://www.google.com/m8/feeds/contacts/userEmail/full/retrieveContactId'/>
    <gd:phoneNumber rel='http://schemas.google.com/g/2005#home'
      primary='true'>
      456
    </gd:phoneNumber>
    <gd:extendedProperty name='pet' value='hamster'/>
    <gContact:groupMembershipInfo deleted='false'
      href='http://www.google.com/m8/feeds/groups/userEmail/base/groupId'/>
  </entry>
  <entry gd:etag='createContactEtag'>
    <batch:id>create</batch:id>
    <batch:operation type='insert'/>
    <batch:status code='201' reason='Created'/>
    <id>http://www.google.com/m8/feeds/contacts/userEmail/base/createContactId</id>
    <updated>2008-12-10T04:45:03.331Z</updated>
    <app:edited xmlns:app='http://www.w3.org/2007/app'>2008-12-10T04:45:03.331Z</app:edited>
    <category scheme='http://schemas.google.com/g/2005#kind'
      term='http://schemas.google.com/contact/2008#contact'/>
    <title>Elizabeth Bennet</title>
    <gd:name>
       <gd:givenName>Elizabeth</gd:givenName>
       <gd:familyName>Bennet</gd:familyName>
       <gd:fullName>Elizabeth Bennet</gd:fullName>
    </gd:name>
    <link rel='http://schemas.google.com/contacts/2008/rel#photo' type='image/*'
      href='https://www.google.com/m8/feeds/photos/media/userEmail/createContactId'/>
    <link rel='self' type='application/atom+xml'
      href='https://www.google.com/m8/feeds/contacts/userEmail/full/createContactId'/>
    <link rel='edit' type='application/atom+xml'
      href='https://www.google.com/m8/feeds/contacts/userEmail/full/createContactId'/>
    <gd:email rel='http://schemas.google.com/g/2005#work' primary='true' address='liz@gmail.com'/>
  </entry>
  <entry gd:etag='newUpdateContactEtag'>
    <batch:id>update</batch:id>
    <batch:operation type='update'/>
    <batch:status code='200' reason='Success'/>
    <updated>2011-05-11T09:30:00.000Z</updated>
    <category scheme='http://schemas.google.com/g/2005#kind'
      term='http://schemas.google.com/contact/2008#contact'/>
    <title type='text'>New Name</title>
    <gd:name>
      <gd:givenName>New</gd:givenName>
      <gd:familyName>Name</gd:familyName>
      <gd:fullName>New Name</gd:fullName>
    </gd:name>
    <content type='text'>Notes</content>
    <link rel='http://schemas.google.com/contacts/2008/rel#photo' type='image/*'
      href='https://www.google.com/m8/feeds/photos/media/userEmail/updateContactId'/>
    <link rel='self' type='application/atom+xml'
      href='https://www.google.com/m8/feeds/contacts/userEmail/full/updateContactId'/>
    <link rel='edit' type='application/atom+xml'
      href='https://www.google.com/m8/feeds/contacts/userEmail/full/updateContactId'/>
    <gd:phoneNumber rel='http://schemas.google.com/g/2005#other'
      primary='true'>456-123-2133</gd:phoneNumber>
    <gd:extendedProperty name='pet' value='hamster'/>
    <gContact:groupMembershipInfo deleted='false'
      href='http://www.google.com/m8/feeds/groups/userEmail/base/groupId'/>
  </entry>
  <entry>
    <batch:id>delete</batch:id>
    <batch:operation type='delete'/>
    <batch:status code='200' reason='Success'/>
    <updated>2011-05-11T09:30:00.000Z</updated>
    <content type='text'>Deleted</content>
    <id>https://www.google.com/m8/feeds/contacts/default/full/deleteContactId</id>
  </entry>
</feed>

public static ContactFeed executeBatchRequest(ContactsService myService)
    throws ServiceException, IOException {
  // Feed that holds all the batch request entries.
  ContactFeed requestFeed = new ContactFeed();

  // Create a ContactEntry for the retrieve request.
  ContactEntry retrieveContact = new ContactEntry();
  retreiveContact.setId("https://www.google.com/m8/feeds/contacts/default/private/full/retrieveContactId");
  BatchUtils.setBatchId(retrieveContact, "retrieve");
  BatchUtils.setBatchOperationType(retrieveContact, BatchOperationType.QUERY);

  // Create a ContactEntry for the create request.
  ContactEntry createContact = new ContactEntry();
  final String NO_YOMI = null;
  Name contactTwoName = new Name();
  name.setFullName(new FullName("Elizabeth Bennet", NO_YOMI));
  name.setGivenName(new GivenName("Elizabeth", NO_YOMI));
  name.setFamilyName(new FamilyName("Bennet", NO_YOMI))
  createContact.setName(name);

  Email primaryMail = new Email();
  primaryMail.setAddress("liz@gmail.com");
  primaryMail.setRel("http://schemas.google.com/g/2005#home");
  primaryMail.setPrimary(true);
  createContact.addEmailAddress(primaryMail);

  BatchUtils.setBatchId(createContact, "create");
  BatchUtils.setBatchOperationType(createContact, BatchOperationType.INSERT);

  // Retrieve the ContactEntry to update.
  ContactEntry updateContact =
      myService.getEntry(new URL("https://www.google.com/m8/feeds/contacts/default/full/updateContactId"),
          ContactEntry.class);
  updateContact.getName().getFullName().setValue("New Name");
  updateContact.getName().getGivenName().setValue("New");
  updateContact.getName().getFamilyName().setValue("Name");
  BatchUtils.setBatchId(updateContact, "update");
  BatchUtils.setBatchOperationType(updateContact, BatchOperationType.UPDATE);

  // Retrieve the ContactEntry to delete.
  ContactEntry deleteContact =
      myService.getEntry(new URL("https://www.google.com/m8/feeds/contacts/default/full/deleteContactId"),
          ContactEntry.class);
  BatchUtils.setBatchId(deleteContact, "delete");
  BatchUtils.setBatchOperationType(deleteContact, BatchOperationType.DELETE);

  // Insert the entries to the batch feed.
  requestFeed.getEntries().add(retrieveContact);
  requestFeed.getEntries().add(createContact);
  requestFeed.getEntries().add(updateContact);
  requestFeed.getEntries().add(deleteContact);

  // Submit the batch request to the server.
  ContactFeed responseFeed =
      myService.batch(new URL("https://www.google.com/m8/feeds/contacts/default/full/batch"),
          requestFeed);

  // Check the status of each operation.
  for (ContactEntry entry : responseFeed.getEntries()) {
    String batchId = BatchUtils.getBatchId(entry);
    BatchStatus status = BatchUtils.getBatchStatus(entry);
    System.out.println(batchId + ": " + status.getCode() + " (" + status.getReason() + ")");
  }
  return responseFeed;
}

public static Feed<Contact> ExecuteBatchRequest(ContactsRequest cr)
{
  // List that holds the batch request entries.
  List<Contact> requestFeed = new List<Contact>();

  // Create a Contact entry for the retrieve request.
  Contact retrieveContact = new Contact();
  retrieveContact.Id = "https://www.google.com/m8/feeds/contacts/default/private/full/retrieveContactId";
  retrieveContact.BatchData = new GDataBatchEntryData("retrieve", GDataBatchOperationType.query);

  // Create a Contact entry for the create request.
  Contact createContact = new Contact();
  createContact.Name = new Name()
      {
        FullName = "Elizabeth Bennet",
        GivenName = "Elizabeth",
        FamilyName = "Bennet",
      };
  createContact.Emails.Add(new EMail()
      {
        Address = "liz@gmail.com",
        Rel = ContactsRelationships.IsHome,
        Primary = true,
      });
  createContact.BatchData = new GDataBatchEntryData("create", GDataBatchOperationType.insert);

  // Retrieve the Contact entry to update.
  Contact updateContact = cr.Retrieve<Contact>(
      new Uri("https://www.google.com/m8/feeds/contacts/default/full/updateContactId"));
  updateContact.Name.FullName = "New Name";
  updateContact.Name.GivenName = "New";
  updateContact.Name.FamilyName = "Name";
  updateContact.BatchData = new GDataBatchEntryData("update", GDataBatchOperationType.update);

  // Retrieve the Contact entry to delete.
  Contact deleteContact = cr.Retrieve<Contact>(
      new Uri("https://www.google.com/m8/feeds/contacts/default/full/deleteContactId"));
  deleteContact.BatchData = new GDataBatchEntryData("delete", GDataBatchOperationType.delete);

  // Insert the entries to the batch feed.
  requestFeed.Add(retrieveContact);
  requestFeed.Add(createContact);
  requestFeed.Add(updateContact);
  requestFeed.Add(deleteContact);

  // Submit the batch request to the server.
  Feed<Contact> responseFeed = cr.Batch(requestFeed, new Uri("https://www.google.com/m8/feeds/contacts/default/full/batch"),
      GDataBatchOperationType.Default);

  // Check the status of each operation.
  foreach (Contact entry in responseFeed.Entries)
  {
    Console.WriteLine(entry.BatchData.Id + ": " + entry.BatchData.Status.Code + " (" + entry.BatchData.Status.Reason + ")");
  }
  return responseFeed;
}

def execute_batch_request(gd_client):
  # Feed that holds the batch request entries.
  request_feed = gdata.contacts.data.ContactsFeed()

  # Create a ContactEntry for the retrieve request.
  retrieve_contact = gdata.contacts.data.ContactEntry()
  retrieve_contact.id = atom.data.Id(
      text='https://www.google.com/m8/feeds/contacts/default/private/full/retrieveContactId')

  # Create a ContactEntry for the create request.
  create_contact = gdata.contacts.data.ContactEntry()
  create_contact.name = gdata.data.Name(
      full_name=gdata.data.FullName(text='Elizabeth Bennet'),
      given_name=gdata.data.GivenName(text='Elizabeth'),
      family_name=gdata.data.FamilyName(text='Bennet'))
  create_contact.email.append(gdata.data.Email(address='liz@gmail.com',
      primary='true', rel=gdata.data.HOME_REL))

  # Retrieve the ContactEntry to update.
  update_contact = gd_client.GetContact('https://www.google.com/m8/feeds/contacts/default/full/updateContactId')
  update_contact.name.full_name = 'New Name'
  update_contact.name.given_name = 'New'
  update_contact.name.family_name = 'Name'

  # Retrieve the ContactEntry to delete.
  delete_contact = gd_client.GetContact('https://www.google.com/m8/feeds/contacts/default/full/deleteContactId')

  # Insert the entries to the batch feed.
  request_feed.AddQuery(entry=retrieve_contact, batch_id_string='retrieve')
  request_feed.AddInsert(entry=create_contact, batch_id_string='create')
  request_feed.AddUpdate(entry=update_contact, batch_id_string='update')
  request_feed.AddDelete(entry=delete_contact, batch_id_string='delete')

  # submit the batch request to the server.
  response_feed = gd_client.ExecuteBatch(request_feed,
      'https://www.google.com/m8/feeds/contacts/default/full/batch')

  for entry in response_feed.entry:
    print '%s: %s (%s)' % (entry.batch_id.text, entry.batch_status.code, entry.batch_status.reason)

  return response_feed

<!-- Request -->
POST /m8/feeds/groups/default/private/full/batch
...

<?xml version='1.0' encoding='UTF-8'?>
<feed xmlns='http://www.w3.org/2005/Atom'
      xmlns:gContact='http://schemas.google.com/contact/2008'
      xmlns:gd='http://schemas.google.com/g/2005'
      xmlns:batch='http://schemas.google.com/gdata/batch'>
  <entry>
    <batch:id>retrieve</batch:id>
    <batch:operation type='query'/>
    <id>https://www.google.com/m8/feeds/groups/default/full/retrieveContactGroupId</id>
  </entry>
  <entry>
    <batch:id>create</batch:id>
    <batch:operation type='insert'/>
    <atom:category scheme="http://schemas.google.com/g/2005#kind"
      term="http://schemas.google.com/contact/2008#group"/>
    <atom:title type="text">Salsa group</atom:title>
    <gd:extendedProperty name="more info about the group">
      <info>Nice people.</info>
  </entry>
  <entry gd:etag='updateContactGroupEtag'>
    <batch:id>update</batch:id>
    <batch:operation type='update'/>
    <category scheme="http://schemas.google.com/g/2005#kind"
      term="http://schemas.google.com/g/2005#group"/>
    <id>http://www.google.com/feeds/groups/userEmail/base/updateContactGroupId</id>
    <published>2005-01-18T21:00:00Z</published>
    <updated>2006-01-01T00:00:00Z</updated>
    <title type="text">New Group Title</title>
    <content type="text">New Group Content</content>
    <link rel='self' type='application/atom+xml'
      href='https://www.google.com/m8/feeds/groups/userEmail/full/updateContactGroupId'/>
    <link rel='edit' type='application/atom+xml'
      href='https://www.google.com/m8/feeds/groups/userEmail/full/updateContactGroupId'/>
  </entry>
  <entry gd:etag='deleteContactGroupEtag'>
    <batch:id>delete</batch:id>
    <batch:operation type='delete'/>
    <id>https://www.google.com/m8/feeds/groups/default/full/deleteContactGroupId</id>
  </entry>
</feed>
<!-- Response -->
HTTP/1.1 200 OK
Content-Type: application/atom+xml;
...

<?xml version='1.0' encoding='UTF-8'?>
<feed xmlns='http://www.w3.org/2005/Atom'
      xmlns:gContact='http://schemas.google.com/contact/2008'
      xmlns:gd='http://schemas.google.com/g/2005'
      xmlns:batch='http://schemas.google.com/gdata/batch'>
  <entry gd:etag='retrieveContactGroupEtag'>
    <batch:id>retrieve</batch:id>
    <batch:operation type='query'/>
    <batch:status code='200' reason='Success'/>
    <id>http://www.google.com/m8/feeds/groups/userEmail/base/retrieveContactGroupId</id>
    <updated>2008-12-10T04:44:37.324Z</updated>
    <category scheme='http://schemas.google.com/g/2005#kind'
      term='http://schemas.google.com/contact/2008#group'/>
    <title>joggers</title>
    <content>joggers</content>
    <link rel='self' type='application/atom+xml'
      href='https://www.google.com/m8/feeds/groups/userEmail/full/retrieveContactGroupId'/>
    <link rel='edit' type='application/atom+xml'
      href='https://www.google.com/m8/feeds/groups/userEmail/full/retrieveContactGroupId'/>
  </entry>
  <entry gd:etag='createContactGroupEtag'>
    <batch:id>create</batch:id>
    <batch:operation type='insert'/>
    <batch:status code='201' reason='Created'/>
    <id>http://www.google.com/m8/feeds/groups/userEmail/base/createContactGroupID</id>
    <updated>2008-12-10T04:44:37.324Z</updated>
    <category scheme='http://schemas.google.com/g/2005#kind'
      term='http://schemas.google.com/contact/2008#group'/>
    <atom:title type="text">Salsa group</atom:title>
    <gd:extendedProperty name="more info about the group">
      <info>Nice people.</info>
    </gd:extendedProperty>
    <link rel='self' type='application/atom+xml'
      href='https://www.google.com/m8/feeds/groups/userEmail/full/createContactGroupID'/>
    <link rel='edit' type='application/atom+xml'
      href='https://www.google.com/m8/feeds/groups/userEmail/full/createContactGroupID'/>
  </entry>
  <entry gd:etag='newUpdateContactGroupEtag'>
    <batch:id>update</batch:id>
    <batch:operation type='update'/>
    <batch:status code='200' reason='Success'/>
    <category scheme="http://schemas.google.com/g/2005#kind"
      term="http://schemas.google.com/g/2005#group"/>
    <id>http://www.google.com/feeds/groups/userEmail/base/updateContactGroupId</id>
    <published>2005-01-18T21:00:00Z</published>
    <updated>2011-05-11T00:00:00Z</updated>
    <title type="text">New Group Title</title>
    <content type="text">New Group Content</content>
    <link rel='self' type='application/atom+xml'
      href='https://www.google.com/m8/feeds/groups/userEmail/full/updateContactGroupId'/>
    <link rel='edit' type='application/atom+xml'
      href='https://www.google.com/m8/feeds/groups/userEmail/full/updateContactGroupId'/>
  </entry>
  <entry>
    <batch:id>delete</batch:id>
    <batch:operation type='delete'/>
    <batch:status code='200' reason='Success'/>
    <updated>2011-05-11T09:30:00.000Z</updated>
    <content type='text'>Deleted</content>
    <id>https://www.google.com/m8/feeds/groups/default/full/deleteContactGroupId</id>
  </entry>
</feed>

public static ContactGroupFeed executeGroupBatchRequest(ContactsService myService)
    throws ServiceException, IOException {
  // Feed that holds all the batch request entries.
  ContactGroupFeed requestFeed = new ContactGroupFeed();

  // Create a ContactEntry for the retrieve request.
  ContactGroupEntry retrieveContactGroup = new ContactGroupEntry();
  retrieveContactGroup.setId("https://www.google.com/m8/feeds/contacts/default/private/full/retrieveContactId");
  BatchUtils.setBatchId(retrieveContactGroup, "retrieve");
  BatchUtils.setBatchOperationType(retrieveContactGroup, BatchOperationType.QUERY);

  // Create a ContactGroupEntry for the create request.
  ContactGroupEntry createContactGroup = new ContactGroupEntry();
  createContactGroup.setTitle(new PlainTextConstruct("Salsa group"));

  ExtendedProperty additionalInfo = new ExtendedProperty();
  additionalInfo.setName("more info about the group");
  additionalInfo.setValue("Nice people.");
  createContactGroup.addExtendedProperty(additionalInfo);
  BatchUtils.setBatchId(createContactGroup, "create");
  BatchUtils.setBatchOperationType(createContactGroup, BatchOperationType.INSERT);

  // Retrieve the ContactGroupEntry to update.
  ContactGroupEntry updateContactGroup =
      myService.getEntry(new URL("https://www.google.com/m8/feeds/groups/default/full/updateContactGroupId"),
                         ContactGroupEntry.class);
  updateContactGroup.setTitle(new PlainTextConstruct("New Group Title"));
  updateContactGroup.setContent(new PlainTextConstruct("New Group Content"));
  BatchUtils.setBatchId(updateContactGroup, "update");
  BatchUtils.setBatchOperationType(updateContactGroup, BatchOperationType.UPDATE);

  // Retrieve the ContactGroupEntry to delete.
  ContactGroupEntry deleteContactGroup =
      myService.getEntry(new URL("https://www.google.com/m8/feeds/groups/default/full/deleteContactGroupId"),
                         ContactGroupEntry.class);
  BatchUtils.setBatchId(deleteContactGroup, "delete");
  BatchUtils.setBatchOperationType(deleteContactGroup, BatchOperationType.DELETE);

  // Insert the entries to the batch feed.
  requestFeed.getEntries().add(retrieveContactGroup);
  requestFeed.getEntries().add(createContactGroup);
  requestFeed.getEntries().add(updateContactGroup);
  requestFeed.getEntries().add(deleteContactGroup);

  // Submit the batch request to the server.
  ContactGroupFeed responseFeed =
      myService.batch(new URL("https://www.google.com/m8/feeds/groups/default/full/batch"),
                      requestFeed);

  // Check the status of each operation.
  for (ContactGroupEntry entry : responseFeed.getEntries()) {
    String batchId = BatchUtils.getBatchId(entry);
    BatchStatus status = BatchUtils.getBatchStatus(entry);
    System.out.println(batchId + ": " + status.getCode() + " (" + status.getReason() + ")");
  }
  return responseFeed;
}

ublic static Feed<ContactGroup> ExecuteGroupBatchRequest(ContactGroupsRequest cr)
{
  // List that holds the batch request entries.
  List<Group> requestFeed = new List<Group>();

  // Create a Group entry for the retrieve request.
  Group retrieveContactGroup = new Group();
  retrieveContactGroup.Id = "https://www.google.com/m8/feeds/groups/default/private/full/retrieveContactGroupId";
  retrieveContactGroup.BatchData = new GDataBatchEntryData("retrieve", GDataBatchOperationType.query);

  // Create a Group entry for the create request.
  Group createContactGroup = new Group();
  createContactGroup.Title = "Salsa group";
  createContactGroup.ExtendedProperties.Add(new ExtendedProperty()
      {
        Name = "more info about the group",
        Value = "Nice people.",
      });
  createContactGroup.BatchData = new GDataBatchEntryData("create", GDataBatchOperationType.insert);

  // Retrieve the Group entry to update.
  Group updateContactGroup = cr.Retrieve<Group>(
      new Uri("https://www.google.com/m8/feeds/groups/default/full/updateContactGroupId"));
  updateContactGroup.Title = "New Group Title";
  updateContactGroup.Content = "New Group Content";
  updateContactGroup.BatchData = new GDataBatchEntryData("update", GDataBatchOperationType.update);

  // Retrieve the Group entry to delete.
  Group deleteContactGroup = cr.Retrieve<Group>(
      new Uri("https://www.google.com/m8/feeds/groups/default/full/deleteContactGroupId"));
  deleteContactGroup.BatchData = new GDataBatchEntryData("delete", GDataBatchOperationType.delete);

  // Insert the entries to the batch feed.
  requestFeed.Add(retrieveContactGroup);
  requestFeed.Add(createContactGroup);
  requestFeed.Add(updateContactGroup);
  requestFeed.Add(deleteContactGroup);

  // Submit the batch request to the server.
  Feed<Group> responseFeed = cr.Batch(requestFeed, new Uri("https://www.google.com/m8/feeds/groups/default/full/batch"),
                                              GDataBatchOperationType.Default);

  // Check the status of each operation.
  foreach (Group entry in responseFeed.Entries)
  {
    Console.WriteLine(entry.BatchData.Id + ": " + entry.BatchData.Status.Code + " (" + entry.BatchData.Status.Reason + ")");
  }
  return responseFeed;
}

def execute_batch_request(gd_client):
  # Feed that holds the batch request entries.
  request_feed = gdata.contacts.data.GroupsFeed()

  # Create a GroupEntry for the retrieve request.
  retrieve_group = gdata.contacts.data.GroupEntry()
  retrieve_group.id = atom.data.Id(
      text='https://www.google.com/m8/feeds/groups/default/private/full/retrieveContactGroupId')

  # Create a GroupEntry for the create request.
  create_group = gdata.contacts.data.GroupEntry()
  create_group.title = atom.data.Title(text='Salsa group')
  create_group.extended_property.append(gdata.data.ExtendedProperty(name='more info about the group', value='Nice people')

  # Retrieve the GroupEntry to update.
  update_group = gd_client.GetGroup('https://www.google.com/m8/feeds/groups/default/full/updateContactGroupId')
  update_group.title.text = 'New Group Title'
  update_group.content.text = 'New Group Content'

  # Retrieve the GroupEntry to delete.
  delete_group = gd_client.GetGroup('https://www.google.com/m8/feeds/groups/default/full/deleteContactGroupId')

  # Insert the entries to the batch feed.
  request_feed.AddQuery(entry=retrieve_group, batch_id_string='retrieve')
  request_feed.AddInsert(entry=create_group, batch_id_string='create')
  request_feed.AddUpdate(entry=update_group, batch_id_string='update')
  request_feed.AddDelete(entry=delete_group, batch_id_string='delete')

  # submit the batch request to the server.
  response_feed = gd_client.ExecuteBatch(request_feed,
                                         'https://www.google.com/m8/feeds/groups/default/full/batch')

  for entry in response_feed.entry:
    print '%s: %s (%s)' % (entry.batch_id.text, entry.batch_status.code, entry.batch_status.reason)

  return response_feed