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Comment: Migrated to Confluence 5.3

Migration from Apache Abdera to Apache Wink

TBD

1) Consuming Atom Documents:

Apache Wink is the perfect solution for consuming and producing Atom, APP and RSS documents. The following section describes how to migrate from Apache Abdera to Apache Wink by providing a set of examples that cover most use cases.

Advantages of Apache Wink over Apache Abdera

  • Standardized APIs (using JAX-RS and JAXB)
  • Support for handling XML and JSON more easily
  • Support for handling RSS and ATOM more easily

This section contains the following topics:

...

1) Consuming Atom Documents

The following code example demonstrates the consumption of Atom documents using Apache Abdera.

Apache Abdera - Click on link to Download - ConsumeAtomUsingAbdera.java

Code Block

Abdera abdera = new Abdera();
Parser parser = abdera.getParser();
URL url = new URL

Apache Abdera

Apache Wink

Code Block

Abdera abdera = new Abdera();
Parser parser = abdera.getParser();
URL url = new URL("http://alexharden.org/blog/atom.xml");
Document<Feed> doc = parser.parse(url.openStream());
Feed feed = doc.getRoot();
System.out.println(feed.getTitle());
for (Entry entry : feed.getEntries()) {
    System.out.println("\t" + entry.getTitle());
}
Code Block

RestClient client = new RestClient();
Resource resource = client.resource("http://alexharden.org/blog/atom.xml");
AtomFeedDocument<Feed> feeddoc = resourceparser.acceptparse(MediaType.APPLICATION_ATOM_XML).get(AtomFeed.classurl.openStream());
Feed feed = doc.getRoot();
System.out.println(feed.getTitle().getValue());
for (AtomEntryEntry entry : feed.getEntries()) {
    System.out.println("\t" + entry.getTitle().getValue());
}

The following code example demonstrates the consumption of Atom documents using Apache Wink.

ConsumeAtomUsingAbdera.java

Apache Wink - Click on link to Download -

ConsumeAtomUsingWink.java

2) a) Producing Atom Documents:

Apache Abdera

Apache Wink

Code Block
protectedRestClient voidclient doGet(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException {
    Abdera abdera = new Abdera();
    Feed= new RestClient();
Resource resource = client.resource("http://alexharden.org/blog/atom.xml");
AtomFeed feed = abderaresource.newFeed();

    feed.setId("tag:example.org,2007:/foo");
    feed.setTitle("Test Feed");accept(MediaType.APPLICATION_ATOM_XML).get(AtomFeed.class);
System.out.println(feed.getTitle().getValue());
for (AtomEntry entry : feed.getEntries()) {
    feedSystem.out.setSubtitleprintln("Feed subtitle");
    feed.setUpdated(new Date\t" + entry.getTitle().getValue());
}

...

2) a) Producing Atom Documents

The following code example demonstrates the production of Atom documents using Apache Abdera.

Apache Abdera - Click on links to Download - ProduceAtomUsingAbdera.java ProduceAtomUsingAbdera_web.xml

Code Block

protected void doGet(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException {
    feed.addAuthor("Shiva HR");
    feed.addLink("http://example.com");
    feed.addLink("http://example.com/foo", "self");

    EntryAbdera entryabdera = new Abdera();
    Feed feed = abdera.addEntrynewFeed();

    entryfeed.setId("tag:example.org,2007:/foo/entries/1");
    entryfeed.setTitle("EntryTest titleFeed");
    entryfeed.setSummaryAsHtmlsetSubtitle("<p>This is the entry title</p>"Feed subtitle");
    entryfeed.setUpdated(new Date());
    entryfeed.setPublishedaddAuthor(new Date()"Shiva HR");
    entryfeed.addLink("http://example.com/foo/entries/1");

    feed.getDocument().writeTo(response.getWriter());
} 
Code Block

protected void doGet(HttpServletRequest request, HttpServletResponse response)
    throws ServletException, IOException {
    AtomFeed feed = new AtomFeedaddLink("http://example.com/foo", "self");

    Entry entry = feed.addEntry();
    feedentry.setId("tag:example.org,2007:/foo/entries/1");
    feedentry.setTitle(new"Entry AtomText("Test Feed")title");
    feedentry.setSubtitle(new AtomText("Feed subtitle"))setSummaryAsHtml("<p>This is the entry title</p>");
    feedentry.setUpdated(new Date());

    AtomPerson person = entry.setPublished(new AtomPersonDate());
    personentry.setNameaddLink("Shiva HRhttp://example.com/foo/entries/1");

    feed.getAuthorsgetDocument().writeTo(response.addgetWriter(person));
} 

The following code example demonstrates the production of Atom documents using Apache Wink.

Apache Wink - Click on links to Download - ProduceAtomUsingWink.java ProduceAtomUsingWink_web.xml

Code Block
protected void doGet(HttpServletRequest request, AtomLink link1 HttpServletResponse response)
    throws ServletException, IOException {
    AtomFeed feed = new AtomLinkAtomFeed();
    link1feed.setHrefsetId("httptag://example.comorg,2007:/foo");
    feed.getLinks().add(link1setTitle(new AtomText("Test Feed"));

    AtomLink link2 = new AtomLink();
    link2.setHref("http://example.com/foo"feed.setSubtitle(new AtomText("Feed subtitle"));
    feed.setUpdated(new Date());

    AtomPerson person = new AtomPerson();
    link2person.setRelsetName("selfShiva HR");
    feed.getLinksgetAuthors().add(link2person);

    AtomEntryAtomLink entrylink1 = new AtomEntryAtomLink();
    entrylink1.setIdsetHref("taghttp://example.org,2007:/foo/entries/1com");
    entryfeed.setTitle(new AtomText("Entry title")getLinks().add(link1);

    AtomTextAtomLink summarylink2 = new AtomTextAtomLink();
    summarylink2.setType(AtomTextType.htmlsetHref("http://example.com/foo");
    summarylink2.setValuesetRel("<p>This is the entry title</p>self");
    entry.setSummary(summaryfeed.getLinks().add(link2);

    AtomEntry entry.setUpdated( = new DateAtomEntry());
    entry.setPublished(new Date());

setId("tag:example.org,2007:/foo/entries/1");
    AtomLink link3 = entry.setTitle(new AtomLinkAtomText("Entry title"));

    AtomText summary  link3.setHref("http://example.com/foo/entries/1"= new AtomText();
    entrysummary.getLinkssetType()AtomTextType.add(link3html);

    feedsummary.getEntries().add(entrysetValue("<p>This is the entry title</p>");
    entry.setSummary(summary);

    AtomFeed.marshal(feed, response.getOutputStreamentry.setUpdated(new Date());
    entry.setPublished(new Date());
}

ProduceAtomUsingAbdera.java ProduceAtomUsingAbdera_web.xml

ProduceAtomUsingWink.java ProduceAtomUsingWink_web.xml

...


    AtomLink link3 = new AtomLink();
    link3.setHref("http://example.com/foo/entries/1");
    entry.getLinks().add(link3);

    feed.getEntries().add(entry);

    AtomFeed.marshal(feed, response.getOutputStream());
}

2) b) Producing Atom Documents - the JAX-RS way

A more elegant way of producing Atom documents using Apache Wink

...

is the JAX-RS way

...

as described below:

...

  1. Open the Eclipse development environment and create a "Dynamic Web Project".
  2. Add Apache Wink & its dependent JARs

...

  1. under Java

...

  1. EE Module Dependencies.
  2. Create a POJO class and a method that creates Atom feed document. Annotate the class & its methods with the required JAX-RS annotations as below:
    ProduceAtom.java
  3. Add org.apache.wink.server.internal.servlet.RestServlet into web.xml and specify the path of above Resource class in it's init-param.
    See ProduceAtomWinkElegant_web.xml and application
  4. Deploy the web-application and access it using the url http://localhost:8080/ProduceAtom_Wink_Elegant/rest/getAtom
  5. Final WAR -> ProduceAtom_Wink_Elegant.zip (add Wink & its dependent JARs under ProduceAtom_Wink_Elegant\WEB-INF\lib and re-zip it as WAR).

...

3) Consuming RSS

...

Documents

The following code example demonstrates the consuming of RSS documents using Apache Abdera.

Apache Wink Abdera - Click on link to Download - ConsumeRssUsingAbdera.java

Code Block
public static void main(String[] args) throws ParseException, IOException {
    System.out.println("Consuming RSS Documents using Abdera...\n");
    Abdera abdera = new Abdera();
    Parser parser = abdera.getParser();
    URL url = new URL("http://www.rssboard.org/files/sample-rss-2.xml");
    Document<RssFeed> doc = parser.parse(url.openStream());
    RssFeed rssFeed = doc.getRoot();
    System.out.println("Title: " + rssFeed.getTitle());
    System.out.println("Description: " + rssFeed.getSubtitle() + "\n");
    int itemCount    int itemCount = 0;
    for (Entry entry : rssFeed.getEntries()) {
        System.out.println("Item " + ++itemCount + ":");
        System.out.println("\tTitle: " + entry.getTitle());
        System.out.println("\tPublish Date: " + entry.getPublished());
        System.out.println("\tDescription: " + entry.getContent());
    }
} 
Code Block

public static void main(String[] args) {
    System.out.println("Consuming RSS Documents using Apache Wink...\n");
    RestClient client = new RestClient();
    String url = "http://www.rssboard.org/files/sample-rss-2.xml";
    Resource resource = client.resource(url);
    RssFeed rss = resource.accept(MediaType.APPLICATION_XML).get(RssFeed.class);
    RssChannel channel = rss.getChannel();
    System.out.println("Title: " + channel.getTitle());
    System.out.println("Description: " + channel.getDescription() + "\n");
    int itemCount = 0;
    for (RssItem item : channel.getItems()) {
        System.out.println("Item " + ++itemCount + ":");
        System.out.println("\tTitle: " + item.getTitle());
        System.out.println("\tPublish Date: " + item.getPubDate());
        System.out.println("\tDescription: " + item.getDescription());
    }
}

ConsumeRssUsingAbdera.java

ConsumeRssUsingWink.java

4) Creating RSS documents:

...

Apache Abdera

...

Apache Wink

...

As of v0.4 Abdera has no support for RSS write.

...

Same as in 2)a) or 2)b). The resource method now returns an RssFeed object instead of AtomFeed object.

Code Block

@Path("/getRss")
public class ProduceRss {
    @GET
    @Produces(MediaType.APPLICATION_XML)
    public Rss getRss() {
        RssFeed rss = new RssFeed();

        RssChannel channel = new RssChannel();
        channel.setTitle("Liftoff News");
        channel.setLink("http://liftoff.msfc.nasa.gov");
        channel.setDescription("Liftoff to Space Exploration.");
        channel.setPubDate(new Date().toString());

        RssItem item = new RssItem();
        item.setTitle("Star City");
        item.setLink("http://liftoff.msfc.nasa.gov/news/2003/news-starcity.asp");
        item.setDescription("How do Americans get ready to work with Russians aboard the International Space Station?");

        channel.getItem().add(item);
        rss.setChannel(channel);
        return rss;
    }

} 

...

 

...

ProduceRss_Wink_Elegant.zip

5) Writing Atom Publishing Protocol (APP) Server:

6) Writing Atom Publishing Protocol (APP) Client:

7) Comparison of Object Models for Atom Syndication Format (ASF)

8) Comparison of Object Models for Atom Publishing Protocol (APP)

...

= 0;
    for (Entry entry : rssFeed.getEntries()) {
        System.out.println("Item " + ++itemCount + ":");
        System.out.println("\tTitle: " + entry.getTitle());
        System.out.println("\tPublish Date: " + entry.getPublished());
        System.out.println("\tDescription: " + entry.getContent());
    }
} 

The following code example demonstrates the consuming of RSS documents using Apache Wink.

Apache Wink - Click on link to Download - ConsumeRssUsingWink.java

Code Block

public static void main(String[] args) {
    System.out.println("Consuming RSS Documents using Apache Wink...\n");
    RestClient client = new RestClient();
    String url = "http://www.rssboard.org/files/sample-rss-2.xml";
    Resource resource = client.resource(url);
    RssFeed rss = resource.accept(MediaType.APPLICATION_XML).get(RssFeed.class);
    RssChannel channel = rss.getChannel();
    System.out.println("Title: " + channel.getTitle());
    System.out.println("Description: " + channel.getDescription() + "\n");
    int itemCount = 0;
    for (RssItem item : channel.getItems()) {
        System.out.println("Item " + ++itemCount + ":");
        System.out.println("\tTitle: " + item.getTitle());
        System.out.println("\tPublish Date: " + item.getPubDate());
        System.out.println("\tDescription: " + item.getDescription());
    }
}

...

4) Producing RSS Documents

Apache Abdera

Apache Abdera version 0.4 does not support RSS write.

Apache Wink

Same as in 2) b) Producing Atom Documents - the JAX-RS way. However the resource method now returns an RssFeed object instead of AtomFeed object.

Apache Wink - Click on link to Download - ProduceRss_Wink_Elegant.zip

Code Block

@Path("/getRss")
public class ProduceRss {
    @GET
    @Produces(MediaType.APPLICATION_XML)
    public Rss getRss() {
        RssFeed rss = new RssFeed();

        RssChannel channel = new RssChannel();
        channel.setTitle("Liftoff News");
        channel.setLink("http://liftoff.msfc.nasa.gov");
        channel.setDescription("Liftoff to Space Exploration.");
        channel.setPubDate(new Date().toString());

        RssItem item = new RssItem();
        item.setTitle("Star City");
        item.setLink("http://liftoff.msfc.nasa.gov/news/2003/news-starcity.asp");
        item.setDescription("How do Americans get ready to work with Russians aboard the International Space Station?");

        channel.getItem().add(item);
        rss.setChannel(channel);
        return rss;
    }
}

...

5) Writing Atom Publishing Protocol (APP) Server

The following steps explain how to implement an APP server as described in the following beautiful article by James Snell: http://www.ibm.com/developerworks/library/x-atompp1/

Apache Abdera

  1. Open the Eclipse development environment and create a "Dynamic Web Project".
  2. Add Apache Abdera & its dependent JARs under Java EE Module Dependencies.
  3. Add the following CollectionAdapter and Provider classes under src/myPackage directory: APP_CollectionAdapter.java APP_ContentProvider.java
  4. Add org.apache.abdera.protocol.server.servlet.AbderaServlet into web.xml and point the following init paramters to the classes added above.
    org.apache.abdera.protocol.server.Provider
    org.apache.abdera.protocol.server.CollectionAdapter
    APP_Server_Abdera_web.xml
  5. Add the following index.jsp which has help on how to perform the APP operations: APP_Server_Abdera_index.jsp
  6. Deploy and run the application.

Final WAR -> APP_Server_Abdera.zip (add Apache Abdera & its dependent JARs under APP_Server_Abdera\WEB-INF\lib and re-zip it as WAR).

Apache Wink

  1. Open the Eclipse development environment and create a "Dynamic Web Project".
  2. Add Apache Wink & its dependent JARs under Java EE Module Dependencies.
  3. Add the following Resource class under src/myPackage directory: EntriesCollection.java
  4. Add org.apache.wink.server.internal.servlet.RestServlet into web.xml and specify the path of above Resource class in it's init-param. APP_Server_Wink_web.xml APP_Server_Wink_application
  5. Add the following index.jsp which has help on how to perform the APP operations: APP_Server_Wink_index.jsp
  6. Deploy and run the application.

Final WAR -> APP_Server_Wink.zip (add Apache Wink & its dependent JARs under APP_Server_Wink\WEB-INF\lib and re-zip it as WAR)

References

...

6) Writing Atom Publishing Protocol (APP) Client

In order to write an Atom Publishing Protocol client refer to the following examples.

Info
titleImportant Note

Make sure that the APP_Server_Abdera.war and the APP_Server_Wink.war provided in the previous example are deployed before running these examples.

Apache Abdera - Click on link to Download - APP_Client_Abdera.java

   1. Acessing Service Document:

Code Block

Document<Service> introspection = abderaClient.get(SERVICE_URL).getDocument();
Service service = introspection.getRoot();
List<Workspace> workspaces = service.getWorkspaces();
for (Workspace workspace : workspaces) {
    System.out.println("\t" + workspace.getTitle());
    List<Collection> collections = workspace.getCollections();
    for (Collection collection : collections) {
        System.out.println("\t" + collection.getTitle() + "\t:\t" + collection.getHref());
    }
    System.out.print("\n");
}

   2. Getting a Feed

Code Block

RequestOptions opts = new RequestOptions();
opts.setContentType("application/atom+xml;type=feed");
ClientResponse response = abderaClient.get(FEED_URL, opts);
Feed feed = (Feed)response.getDocument().getRoot();

   3. Posting an entry to a Feed

Code Block

RequestOptions opts = new RequestOptions();
opts.setContentType("application/atom+xml;type=entry");
ClientResponse response = abderaClient.post(FEED_URL, newEntry, opts);

   4. Putting a change to an Entry

Code Block

RequestOptions opts = new RequestOptions();
opts.setContentType("application/atom+xml;type=entry");
ClientResponse response = abderaClient.put(ENTRY_URL, changedEntry.getDocument(), opts);

   5. Getting an Entry

Code Block

RequestOptions opts = new RequestOptions();
opts.setContentType("application/atom+xml;type=entry");
ClientResponse response = abderaClient.get(ENTRY_URL, opts);
Entry entry = (Entry)response.getDocument().getRoot();

   6. Deleting an Entry

Code Block

ClientResponse response = abderaClient.delete(ENTRY_URL);

Apache Wink - Click on link to Download - APP_Client_Wink.java

   1. Acessing Service Document:

Code Block

Resource resource = restClient.resource(SERVICE_URL);
AppService service = resource.accept(MediaTypeUtils.ATOM_SERVICE_DOCUMENT).get(AppService.class);
List<AppWorkspace> workspaces = service.getWorkspace();
for (AppWorkspace workspace : workspaces) {
    System.out.println("\t" + workspace.getTitle().getValue());
    List<AppCollection> collections = workspace.getCollection();
    for (AppCollection collection : collections) {
        System.out.println("\t" + collection.getTitle().getValue()
            + "\t:\t"
            + collection.getHref());
    }
    System.out.print("\n");
}

   2. Getting a Feed

Code Block

Resource feedResource = restClient.resource(FEED_URL);
AtomFeed feed = feedResource.accept(MediaType.APPLICATION_ATOM_XML).get(AtomFeed.class);

   3. Posting an entry to a Feed

Code Block

Resource feedResource = restClient.resource(FEED_URL);
ClientResponse response =
    feedResource.contentType(MediaType.APPLICATION_ATOM_XML).post(newEntry);

   4. Putting a change to an Entry

Code Block

Resource feedResource = restClient.resource(ENTRY_URL);
ClientResponse response =
    feedResource.contentType(MediaType.APPLICATION_ATOM_XML).put(changedEntry);

   5. Getting an Entry

Code Block

Resource feedResource = restClient.resource(ENTRY_URL);
AtomEntry atomEntry = feedResource.accept(MediaType.APPLICATION_ATOM_XML).get(AtomEntry.class);

   6. Deleting an Entry

Code Block

Resource feedResource = restClient.resource(ENTRY_URL);
ClientResponse response = feedResource.delete();

...