stella.net

Class ParameterRelay

java.lang.Object

util.PropertyContainer

util.PropertyResources

util.rmi.RmiPropertyContainer

util.rmi.AbstractRmiCaster

stella.CastingContainer

stella.net.ReceiverServer

stella.net.ParameterRelay

All Implemented Interfaces:

Cloneable, Runnable, Remote, ErrorProcessing, CancelRunnable, ExitCleaning, Initializable, PropertySupplying, ResourceSupplying, RmiCaster, RmiPropertyBearing

public class ParameterRelay
extends ReceiverServer

A parameter server class. This class allows clients to connect to its listening port to query instances of RemoteParameters. The functionality is as follows.

• After starting the server with the startServer() method it aquires a listening state on the port defined by #KEY_PORT.
• Incomming request spawn a new ParameterRelay.ParameterHandler thread. This thread reads in the name of the parameter to be querried from the client.
• The parameter name is than looked-up in a known-parameter list. If not present, the registry is asked for a binding with the given name. If such a binding exists and is linke to a RemoteParameter instance, it is stored in the look-up list for further reference. The remote paramter is then queried with its RemoteParameter.remoteGet() method to deliver the object requested.
• The object is converted to a string that is written to the socket-stream. The stream is terminated with a newline and flushed.
• This ends the protocol. The streams and the sockets are closed.

The parameter relay runs as stand-alone.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
protected class	ParameterRelay.ParameterHandler The helper class to run the protocol for ascii-based parameter exchanges.
static class	ParameterRelay.Run Runs the parameter realy.

Nested classes/interfaces inherited from class util.PropertyResources

PropertyResources.Load, PropertyResources.URLResource

Field Summary

Fields

Modifier and Type	Field and Description
private static long	DEFTIMEOUT The default sleep interval between available queries.
static String	KEY_HOST The key to the host where the registry runs.
static String	KEY_TIMEOUT The key for join-time on cancel.
private Map	lookup The look-up table matching names to remote parameters.
private static ThreadGroup	parameterGroup The thread group commands run in.
private Registry	registry The registry, where parameters are look-up.
private ParameterRelay.ParameterHandler	request The handler for dealing with parameter queries.

Fields inherited from class stella.net.ReceiverServer

DEFSERVERPORT, handlerGroup, KEY_BUFFERSIZE, KEY_HANDLERPRIORITY, KEY_HOSTADDRESS, KEY_LOGOUT, KEY_RECEIVERNAME, KEY_SERVERPORT, KEY_SERVERPRIORITY

Fields inherited from class util.rmi.AbstractRmiCaster

ALTERNATEHOST, ALTERNATEPORT, KEY_BINDNAME, KEY_EXPORTPORT, KEY_REGISTRYHOST, KEY_REGISTRYPORT

Fields inherited from class util.PropertyResources

KEY_NOINITONCREATE, POSTFIX_ALPHABET, POSTFIX_BYTES, POSTFIX_DIR, POSTFIX_EXT, POSTFIX_FILE, POSTFIX_LIST, POSTFIX_MODTIME, POSTFIX_URL

Fields inherited from class util.PropertyContainer

KEY_LISTSEPARATOR, KEY_MAPKEYVALUECHAR, KEY_MAPSEPARATOR

Fields inherited from interface util.ResourceSupplying

KEY_URLRESOURCES, KEY_URLUSECONFIG, KEY_URLUSECURRENT, KEY_URLUSEHOME

Fields inherited from interface util.PropertySupplying

CONFIG, KEY_CLASS

Constructor Summary

Constructors

Constructor and Description
ParameterRelay(Map prop) Constructs a new parameter server.

Method Summary

Modifier and Type	Method and Description
void	cancel() Cancels the parameter server.
protected void	protocol(Socket client) The method called as soon as a connection is established.
void	startServer() Starts the server.

Methods inherited from class stella.net.ReceiverServer

exit, getAsociatedThread, getBufferSize, getHandlerPriority, getReceiverName, getServerPort, getServerPriority, init, initReceiverServer, maxTimeToCancel, processError, run

Methods inherited from class stella.CastingContainer

addErrorListener, addRmiErrorListener, isValid, notifyErrorListener, removeErrorListener, removeRmiErrorListener, sendError, sendError, sendError, sendStatus, sendStatus, sendStatus

Methods inherited from class util.rmi.AbstractRmiCaster

bindToRegistry, bindToRegistry, bindToRegistry, bindToRegistry, bindToRegistry, bindToRegistry, casterExit, casterExit, getBindName, getBindName, unbindFromRegistry, unbindFromRegistry

Methods inherited from class util.rmi.RmiPropertyContainer

containsRemoteProperty, getRemoteProperties, getRemoteProperty, setRemoteProperty

Methods inherited from class util.PropertyResources

clone, createFrom, createFrom, createFrom, createInstance, getApplet, getAsResources, getLocate, getPropertiesToKey, getPropertiesToKey, getResource, getResourceAsStream, getResourceFromKey, getResources, hasLocalURLs, initProperties, keyCreate, keyCreate, reload, setApplet

Methods inherited from class util.PropertyContainer

augment, augment, augment, augment, augment, defaultBoolean, defaultChar, defaultDouble, defaultFloat, defaultInt, defaultLong, defaultObject, defaultObject, defaultProperties, defaultProperty, getAsBoolean, getAsChar, getAsDouble, getAsEnums, getAsFloat, getAsInt, getAsList, getAsLong, getAsMap, getAsMap, getAsObject, getAsObject, getProperties, getProperty, has, isNew, parseObject, parseObject, reload, removeProperty, requires, rescanned, setObject, setProperties, setProperty, stringProperties, toString

Methods inherited from class java.lang.Object

equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface util.PropertySupplying

defaultBoolean, defaultChar, defaultDouble, defaultFloat, defaultInt, defaultLong, defaultObject, defaultObject, defaultProperties, defaultProperty, getAsBoolean, getAsChar, getAsDouble, getAsFloat, getAsInt, getAsList, getAsLong, getAsMap, getAsObject, getAsObject, getProperties, getProperty, has, parseObject, removeProperty, setObject, setProperty, stringProperties

Field Detail

KEY_HOST

public static final String KEY_HOST

The key to the host where the registry runs.

See Also:

Constant Field Values

KEY_TIMEOUT

public static final String KEY_TIMEOUT

The key for join-time on cancel.

See Also:

Constant Field Values

DEFTIMEOUT

private static final long DEFTIMEOUT

The default sleep interval between available queries.

See Also:

Constant Field Values

parameterGroup

private static final transient ThreadGroup parameterGroup

The thread group commands run in.

request

private ParameterRelay.ParameterHandler request

The handler for dealing with parameter queries.

lookup

private Map lookup

The look-up table matching names to remote parameters.

registry

private Registry registry

The registry, where parameters are look-up.

Constructor Detail

ParameterRelay

public ParameterRelay(Map prop)
               throws RemoteException

Constructs a new parameter server. The server thread must be started explicetly with a call to startServer().

Throws:

RemoteException

Method Detail

startServer

public void startServer()

Starts the server. The linked thread is already constructed in ReceiverServer.ReceiverServer(Map), which also sets the server priority.

cancel

public void cancel()

Cancels the parameter server. If a connection is currently active, it is first closed.

Specified by:

cancel in interface CancelRunnable

Overrides:

cancel in class ReceiverServer

protocol

protected void protocol(Socket client)

The method called as soon as a connection is established. It spwans a ParameterRelay.ParameterHandler thread witch performs the actual communication.

Specified by:

protocol in class ReceiverServer

Parameters:

client - The client socket.

See Also:

CommandReceiver, ErrorReceiver