6.2 Configuration

The client as well as the server has to be configured in order to function properly. Both, the client and the server, must be configured through a set of configurtation properties.

6.2.1 Configuration Properties

A configuration property can be considered a variable whose value is read by the DGL system during runtime. In most cases, only few properties have to be set. The software should run with most of the properties set to the default value. There are two ways how to set the configurtation properties.

• Define the properties in the configuration file. The server as well as the client has a specific file in which those properties are defined.
• Set properties through command line.

Properties for server and client:

Property	Description	Default Value
server	The host name of the machine on which the daemon and server processes are running. This property must be set in any case.
localhost	Due a bug in Java it is impossible for the DGL server on some platforms to determine the local host name. ( localhost is always returned instead of the real host name). In this case, the host name must be stated with this property.
rmilogging	Can be true or false. If set to true, it dumps RMI debug information to the console.	false
rminame	Specifies the RMI Object Name of the daemon. This name identifies the daemon within the RMI object space on the server. In most cases this should not be changed. It is needed if more then one daemon should run on the same machine.	GippDaemon
rmiport	The port number under which the clients can connect to the rmiregistry of the server.	10555
logdir	The directory, which is used to store the log files. The server stores logs in files named sessionname.log. The daemon process stores its log information into daemon.log.	.
dbglevel	This must be set to a numerical value from 0 upward. A value of 0 means that no log messages are written to the log file(s). The higher this number, the more detailed log messages are written to the log file(s). E.g., A value of 1 produces only the most important debug messages.	1

Properties for the server only:

Property	Description	Default Value
codebase	On some machines, this is needed to define the path for the Java class files.
serverexec	The command string, which is used by the daemon to spawn a new server.
sessiondir	The directory, which is used to store and reload session files from. Sessions are stored to file named like: sessioname.gip.	.
serverlog	Values: true or false. Server debug and log messages are only written if this property is set to true.	false
daemonlog	Values: true or false. Daemon debug and log messages are only written if this property is set to true.	false

Properties for the client only:

Property	Description	Default Value
user	Default user name that is used for logging into the server. Note, that the user name can still be changed by the user in the login dialog.
logfile	Declares the filename, which is used to store debug messages. No debug information is stored if this variable is not specified.
offline	Values: true or false. The client is forced into offline mode if this property is set to true. Offline mode means, that the client will not contact the server. Although, images can be loaded, manipulated and stored. Those operations are however local and not distributed.	false

The application will run with most of the properties set to there default values. However, there are some properties, which must be set in any case:

• For the server, the properties server and serverexec must be set.
• In most cases, the client should run with only the property server set to an appropriate value.

6.2.2 Configuration File

The configuration file is a text file that specifies a set of configuration properties. The default name for the server configuration file is server.config and the client config-file has the default name client.config. Each line in a config-file begins with the name of a property followed by ``='' and the value of the property. Comments can be included by preceding them with the strings ``#'' or ``//''.

Example:

  # CLIENT Configuration File for Distributed Graphics Laboratory
  # Author : Norbert Harrer
  # configuration for machine rijeka.sdsu.edu

  server  = opatija.sdsu.edu
  rmiport = 10555
  user    = Norbert                        # default user name

  // optional options:
  // rminame    = DaemonPort               # Default Daemon RMI Name
  // localhost  = rijeka.sdsu.edu          # local IP Address

6.2.3 Command line options

Each property, which can be specified in a configuration file, can also be passed to the client or the server as a command line option. Properties set by command line options have higher priority and override values specified in a configuration file.

There is also an additional command line option named configfile that overrides the default file name for the configuration file. The default client configuration file is client.config. The server default configuration file is named server.config.

Syntax:

  java gipp.Client [-option value]*
  java gipp.Daemon [-option value]*

Example:

  java gipp.Client -configfile c.config -server
  opatija.sdsu.edu -user test