Abstract: A method, apparatus, system, and signal-bearing medium that, in an embodiment, send a broadcast message to a cluster of servers receive a point-to-point message from a coordinating server of the cluster, where the coordinating server joined the cluster before all other servers in the cluster. The point-to-point message includes routing data regarding all of the servers in the cluster. In an embodiment, the broadcast message includes a record that includes an identification of a new server, resource data regarding the new server, and a time that the new server joins the cluster, and the servers in the cluster add the record to the routing data and send a request to the new server via the record. In another embodiment, the broadcast message includes records for all servers in a second cluster, and the new server sends the routing data to the servers in the second cluster. If a server leaves the cluster, its record is removed.

Abstract: A method, apparatus, system, and signal-bearing medium that, in an embodiment, receive a change request from a first client at a first time, where the change request includes a key that identifies a field in a data object. A determination is made that the first client changed the field identified by the key at a second time that is before the first time and that a second client changed the field identified at a third time that is after the second time and before the first time, and the key is sent to the second client. The client receives the key, and in various embodiments invalidates the key in a cache or removes the key from the cache. In an embodiment, the data value of the change request is also sent to the second client, which updates the cache with the data value. In this way, stale data in a cache at a client is either updated or removed.

Abstract: One computer system in a cluster includes a dynamic routing mechanism that receives all incoming messages for the cluster. When a message is received, the dynamic routing mechanism checks its dynamic routing table, and routes a message to the appropriate partition that corresponds to the address of the message. If a resource has been moved to a different partition, the dynamic routing mechanism may route the message to the old partition instead of the new one. In this case, the old partition receives the message, determines whether the message is intended for it, and if not, the partition forwards the message to the appropriate target partition. The partition then notifies the dynamic routing mechanism of the change in location of the resource, which causes the dynamic routing mechanism to update its dynamic routing table to reflect the change in location for the resource.

Abstract: A container managed persistent (CMP) enterprise java bean (EJB) framework includes support for accessing multiple data sources within one deployment. A CMP EJB includes a number of different attributes that can be a variety of values. A session EJB that acts as a front-end to the CMP EJP includes a resource reference for each of the different data sources that the entity CMP EJB may utilize. The application server environment includes a map that defines mapping information between the attributes of the CMP EJB and the resource references of the session EJB. Using the mapping information during runtime, the application server connects to the appropriate data source.