Step 2: Creating a Navigation
Connector
The navigation connector implements methods that define the following:
● The initial (top-level) nodes of the connector. Once the navigation connector returns the initial nodes, the navigation service can query the nodes themselves for each one’s children and related nodes.
● The mapping between a navigation URL and the nodes defined by the connector.
For example, if the connector prefix is myPrefix, a navigation URL for the connector could be myPrefix://myParentNode2/myChildNode5. The connector must determine what INavigationConnectorNode object to return for this URL.
Procedure
...
1. Create a new class that extends AbstractNavigationConnector.
2. Implement the method getInitialNodes(), which returns a javax.naming.NamingEnumeration of the initial nodes. The method could return the nodes only if a condition is true, for example, the user is part of specific role.
The following returns the initial nodes if the user is part of the Java developer role:
public NamingEnumeration getInitialNodes(Hashtable environment) {
if (isUserInJavaDeveloperRole(environment))
return new NavigationEnum(initialNodes);
else
return NavigationEnum.EMPTY_ENUM;
}
3. Implement the method getNode(), which returns a INavigationConnectorNode based on a navigation URL passed into the method.
You can implement any logic for returning the INavigationConnectorNode object. One method is to store all the nodes in a Map with the navigation URL as the key. To implement this, you could do the following:
a. Store the nodes in a Map. You can add code for this in an initialization method.
One implementation is to create a method that recursively traverses the navigation nodes that you created and store them in a map with the fully qualified name (navigation URL) as the key for each one, as follows:
private void recursivelyFillNamesToNodesMap(NamingEnumeration enum)
throws NamingException {
while (enum.hasMoreElements()) {
Binding b = (Binding) enum.nextElement();
myConnectorNode node = (myConnectorNode) b.getObject();
String nodeName = node.getName();
namesToNodes.put(nodeName, node);
atomicNamesToNames.put(node.getAtomicName(),nodeName);
recursivelyFillNamesToNodesMap(node.listBindings(
"", INavigationConnectorNode.NAVIGATION_GET_CHILDREN));
}
}
You could then call recursivelyFillNamesToNodesMap from the initialization method, passing in the initial nodes.
b. Look up the node in the Map based on the navigation URL. The following returns a node in the namesToNodes Map if the user is a member of the Java developer role:
public INavigationConnectorNode getNode(
Hashtable environment, String
connectorNodeURL) {
boolean memberOfRole = isUserInJavaDeveloperRole(environment);
if (memberOfRole)
return (myConnectorNode) namesToNodes.get(connectorNodeURL);
else
return null;
}
4. Implement the method getNodes(), which returns a javax.naming.NamingEnumeration of INavigationConnectorNode objects based on a set of navigation URLs passed into the method, as follows:
public NamingEnumeration getNodes(
Hashtable environment, Vector
connectorNodeURLs) {
myConnectorNode node;
int size = connectorNodeURLs.size();
List nodeBindings = new ArrayList(size);
for (int i = 0; i < size; i++) {
node = (myConnectorNode)
getNode(
environment, (String) connectorNodeURLs.get(i));
if (node != null) nodeBindings.add(
new Binding(node.getName(), node));
}
return new NavigationEnum(nodeBindings);
}
5. Implement the method getNodeByQuickLink() in order to map quick links strings to specific navigation nodes.
For more information, see Quick Links.
6. Implement getConnectorCacheDiscriminators(), which returns a set of keys, with each key representing a different entry point. The method enables caching of navigation nodes, improving performance.
For more information, see Navigation Cache.
If your navigation connector does not support caching, implement getConnectorProfile(), and return a NavigationConnectorProfile object on which you called setCachable() and turned caching off.