Java Dynamic Management Kit 5.0 Tutorial

Establishing a Connection

The target of a connection is identified by a protocol-specific implementation of the ConnectorAddress interface. This object contains all the information that a connector client needs to establish a connection with the target agent. All address objects specify a host name and port number. An RMI address adds the required service name, and HTTP-based addresses have an optional authentication field (see Password-Based Authentication). In addition, the ConnectorType string identifies the protocol without needing to introspect the address object.

In our example, the target of the connection is an active RMI connector server identified by an RmiConnectorAddress object. We use the default constructor to instantiate a default address object, but otherwise, these parameters can be specified in a constructor or through setter methods. The default values of the information contained in the RmiConnectorAddress object are the following:

The RmiConnectorAddress object is used as the parameter to the connect method of the RmiConnectorClient instance. This method tries to establish the connection and throws an exception if there is a communication or addressing error. Otherwise, when the connect method returns, the connector client is ready to perform management operations on the designated agent.

Example 10–3 Establishing a Connection

echo("\t>> Instantiate the RMI connector client...");
connectorClient = new RmiConnectorClient();

echo("\t>> Instantiate a default RmiConnectorAddress object...");
RmiConnectorAddress address = new RmiConnectorAddress();

// display the default values
echo("\t\tTYPE\t= "   + address.getConnectorType());
echo("\t\tPORT\t= "   + address.getPort());
echo("\t\tHOST\t= "   + address.getHost());
echo("\t\tSERVER\t= " + address.getName());
echo("\t<< done <<");

echo("\t>> Connect the RMI connector client to the agent...");
try {
     connectorClient.connect( address );

} catch(Exception e) {
     echo("\t!!! RMI connector client could not connect to the agent !!!");