Using a target template

In your Atom feed implementation class, you can use the target templates that have been defined in the Atom plug-in framework configuration file.

A target template defines a URL template structure that your implementation class can use to build URLs. For details of the target template, and how it is defined in the Atom plug-in framework configuration file, refer to the target-template topic.

You can access a target template from the requestContext object, which is passed to the methods that your implementation class inherits from the ServiceRegistryFeedAdapter class.

Example

This example uses a target template called "AccountTemplate" that has the following definition in the Atom plug-in framework configuration file:

<target-template>
  <template-name>AccountTemplate</template-name>
  <template>{target_base}/account/{account_number}</template>
</target-template>

The following getFeed method substitutes the value "ABC123" for the {account_number} variable in the definition. The variable {target_base} is replaced automatically with the root of the request URL. The resulting URL has the form "http://hostname:port/ServiceRegistryFeeds/context-root/account/ABC123".

public ResponseContext getFeed(RequestContext requestContext) {
          .
          .
          .
  Map<String,String> params = new HashMap<String,String>();
  params.put("account_number", "ABC123");
  String absoluteUrl = requestContext.absoluteUrlFor("AccountTemplate", params);
          .
          .
          .

}

Note: In this example, the URL prefix "http://hostname:port" is based on the server that processed the HTTP request. However, you can define your own URL prefix in an environment-specific attribute and access that value in your implementation class; this might be useful, for example, in a cluster configuration. See The FeedContext interface for details.