Standard Directory Facilitator agent. This class implements FIPA DF agent. JADE applications typically don't use this class directly, but interact with the DF agent through ACL message passing. The DFService class provides a number of static methods that facilitate this task. More DF agents can be created by application programmers to divide a platform into many Agent Domains.
A DF agent accepts a number of optional configuration parameters that can be set either as command line options or within a properties file (to be passed to the DF as an argument).
| Parameter | Description |
|---|---|
jade_domain_df_autocleanup | If set to true, indicates that the DF will automatically clean up registrations as soon as an agent terminates. The default is false |
jade_domain_df_maxleasetime | Indicates the maximum lease time (in millisecond) that the DF will grant for agent description registrations (defaults to infinite). |
jade_domain_df_maxresult | Indicates the maximum number of items found in a search operation that the DF will return to the requester (defaults to 100). |
jade_domain_df_disablevalidation | Turns off content validation on incoming/outgoing messages (defaults to false) |
jade_domain_df_db-default | If set to true, indicates that the DF will store its catalogue into an internal HSQL database, running within the same VM. (The HSQL jar files have to added to the Java CLASSPATH) |
jade_domain_df_db-url | Indicates the JDBC URL of the database the DF will store its catalogue into. This parameter is ignored if jade_domain_df_db-default is set. If neither this parameter nor jade_domain_df_db-default is specified the DF will keep its catalogue in memory. |
jade_domain_df_db-driver | Indicates the JDBC driver to be used to access the DF database (defaults to the ODBC-JDBC bridge). This parameter is ignored if jade_domain_df_db-url is not set or jade_domain_df_db-default is set. |
jade_domain_df_db-username, jade_domain_df_db-password | Indicate the username and password to be used to access the DF database (default to null). These parameters are ignored if jade_domain_df_db-url is not set or jade_domain_df_db-default is set. | jade_domain_df_db-cleantables | If set to true, indicates that the DF will clean the content of all pre-existing database tables, used by the DF. This parameter is ignored if the catalogue is not stored in a database. |
jade_domain_df_db-abortonerror | If set to true, indicates that the DF will immediately terminate in case it cannot connect to the database. This parameter is ignored if the catalogue is not stored in a database. |
jade_domain_df_kb-factory | Indicates the name of the factory class that should be used to create the knowledge base objects for the DF. The class has to be a sub class of jade.domain.DFKBFactory. |
jade_domain_df_poolsize | The dimension of the pool of thread dedicated to serving registration, deregistration and search requests. If 0 (default) is specified then registration, deregistration and search requests are served directly by the df agent Thread. This parameter is ignored when using a volatile (in-memory) knowledge base. |
For instance the following command line will launch a JADE main container with a DF that will store its catalogue into a database accessible at URL jdbc:odbc:dfdb and that will keep agent registrations for 1 hour at most. java jade.Boot -gui -jade_domain_df_db-url jdbc:odbc:dfdb -jade_domain_df_maxleasetime 3600000
Each DF has a GUI but, by default, it is not visible. The GUI of the agent platform includes a menu item that allows to show the GUI of the default DF. In order to show the GUI, you should simply send the following message to each DF agent: (request :content (action DFName (SHOWGUI)) :ontology JADE-Agent-Management :protocol fipa-request)
@see DFService
@author Giovanni Rimassa - Universita' di Parma
@author Tiziana Trucco - TILAB S.p.A.
@author Elisabetta Cortese - TILAB S.p.A.
@author Giovanni Caire - TILAB
@author Roland Mungenast - Profactor
@version $Date: 2007-03-30 18:30:14 +0200 (ven, 30 mar 2007) $ $Revision: 5952 $
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