| The MultiHostHandler allows the user to handle a set
of host names that are all running on the same IP address. This
handler looks at the "Host:" and redispatches the request to the
appropriate sub-server.
Only the main server is actually listening to the port on the specified IP
address. The sub-servers are not running in separate threads. Indeed,
they are not "running" at all. They exist merely as a convenient bag to
hold each of the server-specific configuration parameters.
The respond method of the main handler for the appropriate
sub-server is called directly from the respond method of
this handler.
This handler uses the following configuration parameters:
- servers
- The list of prefixes for the other servers. Each server will be
initialized from the main
server.props with the
specified prefix. In this way, the configuration parameters for
all the sub-servers can be stored in the same Properties
object.
- prefix.host
- Each server is started with a given prefix. The property
prefix.host specifies the virtual hostname that the server
will be expected to handle. If this property is not specified,
the server's virtual hostname will just be prefix.
- prefix.handler
- The main handler for the server with the given prefix. If
this property is not specified, it defaults to the
FileHandler.
- prefix.log
- The log level for the server with the given prefix. If this
property is not specified, it defaults to the log level of the
parent server.
A sample set of configuration parameters illustrating how to use this
handler follows:
handler=host
port=8081
log=5
host.class=sunlabs.brazil.server.MultiHostHandler
host.servers=mars jupiter saturn
mars.host=www.mars.com
mars.log=2
mars.handler=mars.file
mars.file.class=sunlabs.brazil.server.FileHandler
mars.file.root=public_html/mars
jupiter.host=jupiter.planet.org
jupiter.handler=sunlabs.brazil.server.FileHandler
jupiter.root=public_html/jupiter
saturn.host=saturn.planet.org
saturn.handler=sunlabs.brazil.server.FileHandler
saturn.root=public_html/saturn
These parameters set up a normal Server on port 8081,
running a MultiHostHandler. The MultiHostHandler
will create three additional servers that respond to the virtual hosts
"www.mars.com", "jupiter.planet.org", and "saturn.planet.org". The
"mars" server will have a Server.prefix of "mars",
so that all other configuration parameters that the "mars" server
examines can begin with "mars" and be kept distinct from the "jupiter"
and "saturn" parameters.
In fact, the main server and the three sub-servers will all share the
same properties object, but can use their own individual prefixes to
keep their data separate.
NOTE: This handler is in the Server package because it depends
on implementation details of the Server and Request classes, not
because it represents essential or "core" functionallity.
author:
Colin Stevens (colin.stevens@sun.com)
version:
1.5, 00/12/11 |
