Program guide > (deprecated) Partitioning facility > Partitioning facility programming > HTTP partitions > HTTP programming interfaces


Deprecated feature: The partitioning facility (WPF) feature is deprecated. You can configure partitioning with WebSphere eXtreme Scale.


The notification interface

The servlet API consists of a method for receiving partition callbacks (regarding partition events) using the HttpPartitionNotification interface. The notification interface is...

public interface HttpPartitionNotification {
        /* 
         * Fetch the vector of partition strings from the web module.
         */
        public Vector getPartitions();
    
        /* 
         * Fetch the array of expressions from the web module.
         */
        public HttpPartitionExpression[] getExpressions();
    
        /* 
         * Queries the web module to determine if the specified partition 
      is still alive.
         */
        public boolean isPartitionAlive(String partitionName);
    
        /* 
         * Indicates that this partition has been loaded by WPF.
         */
        public boolean loadEvent(String partitionName);
    
        /* 
         * Indicates that this partition has been loaded by WPF.
         */
        public void unloadEvent(String partitionName);
    }

Though this interface is very similar to that supported by the partitioning facility function, there are some minor differences. The most notable of these is the inclusion of a getExpressions() method that is used by the HTTP partitioning function to gather the request expressions that will be used with this application. A servlet can register itself (or some other class) to receive notifications by invoking the HttpPartitionManager.registerNotfication() method, for example, in its init() method:

public void init() throws ServletException {
        System.out.println(className+": Registering notification ");
        httpPartitionManager.registerNotification(appName, this);
      }
    
    public void destroy() {
       System.out.println(className+": Deregistering notification ");
        httpPartitionManager.deregisterNotification(appName, this);
        }

This example also illustrates the use of the HttpPartitionManager.deregisterNotfication() method in the servlet's destroy() method. For correctness, all registered notifications must be deregistered.


Parent topic:

HTTP programming interfaces


Related concepts

HTTP programming interfaces