ReceiverServer

java.lang.Object
- util.PropertyContainer
- - util.PropertyResources
  - - util.rmi.RmiPropertyContainer
    - - util.rmi.AbstractRmiCaster
      - stella.CastingContainer
        
        stella.net.ReceiverServer

All Implemented Interfaces:

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

Direct Known Subclasses:

ErrorServer, ParameterRelay
```
public abstract class ReceiverServer
extends CastingContainer
implements CancelRunnable, ErrorProcessing, Initializable, ExitCleaning
```
The receiver server base class. This abstract class is listening to the port specified in its properties. When a connection is established the abstract method protocol(java.net.Socket) is called with the client socket as an argument which is an abstract method in the base implementation. Concrete subclasses should provide their implementations of the protocol, like CommandReceiver or ErrorReceiver.
The details of this class's functionality can be described as follows.
- On startup this class creates a server socket listening on the port specified in the properties of this receiver.
- When a connection is established a helper thread is spawned. The helper thread, normally a subclass of Handler, takes over the client socket and is responsible for the entire communication ('protocol').
- The main receiver class immediately retakes the listening state once the protocol thread is started.
- The Handler first establishes the streams to the client and reads in the command sent by the client.
- It provides a Handler.close() method that closes the streams and the socket.
For convenience, the receiver server implements the Runnable interface. During construction (exactly in the init() method), a Thread is initialized with is directly linked with this receiver server. It can be querried with getAsociatedThread(). If full thread behaviour is intended, some parts of the codes have to be updated. The run method loops forever unless cancel is called.

Nested Class Summary
- Nested classes/interfaces inherited from class util.PropertyResources
  PropertyResources.Load, PropertyResources.URLResource

Field Summary

Fields
Modifier and Type	Field and Description
`private boolean`	`cancel` Gets true if this thread should exit.
`private static int`	`COUNT` An internal counter for automatic naming.
`private static int`	`DEFBUFFERSIZE` The default buffer size of the I/O streams `(2048)`.
`private static int`	`DEFHANDLERPRIORITY` The default handler thread priority `(Thread.NORM_PRIORITY)`.
`private static long`	`DEFLOGOUT` The default log-out time granted to clients.
`private static String`	`DEFRECEIVERNAME` The default receiver `(Receiver-)`.
`static int`	`DEFSERVERPORT` The default port number `(1026)`.
`private static int`	`DEFSERVERPRIORITY` The default server thread priority `(1)`.
`protected ThreadGroup`	`handlerGroup` The thread group handlers run in.
`static String`	`KEY_BUFFERSIZE` The key in the properties for the stream buffer size.
`static String`	`KEY_HANDLERPRIORITY` The key in the properties defining the priority of the server.
`static String`	`KEY_HOSTADDRESS` The key to the host running the server.
`static String`	`KEY_LOGOUT` The key for the log-out time granted to the clients.
`static String`	`KEY_RECEIVERNAME` The key in the properties defining the name of this receiver.
`static String`	`KEY_SERVERPORT` The key for the socket port to listen to.
`static String`	`KEY_SERVERPRIORITY` The key in the properties defining the priority of the server.
`private ServerSocket`	`listen` The server socket the server listens to.
`private Thread`	`thisThread` A reference to the thread constructed from this Runnable.

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
Modifier Constructor and Description

protected ReceiverServer(Map qualify)
Constructs a new receiver with the specified properties.

Constructors
Modifier	Constructor and Description
`protected`	`ReceiverServer(Map qualify)` Constructs a new receiver with the specified properties.

Method Summary

All Methods Static Methods Instance Methods Abstract Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`cancel()` Cancels the server thread.
`void`	`exit()` Closes the receiver socket.
`Thread`	`getAsociatedThread()` Returns the thread asociated with this server.
`int`	`getBufferSize()` Returns the buffer size used for buffering the socket streams.
`int`	`getHandlerPriority()` Returns the priority at which the connection handler thread should run.
`String`	`getReceiverName()` Returns the name used for binding this receiver.
`int`	`getServerPort()` Returns the port number the clients should connect to on this receiver.
`int`	`getServerPriority()` Returns the priority at which this thread (the server) should run.
`void`	`init()` Initializes the receiver server.
`protected void`	`initReceiverServer()` An escape pod for subclasses.
`long`	`maxTimeToCancel()` Returns the maximum time-out for this thread.
`private static int`	`nextCount()` Gets the next available number at automatic naming.
`void`	`processError(ErrorEvent ee)` An escape pod for subclasses that want to do anything special with errors or exceptions thrown during the lifecycle of this thread.
`protected abstract void`	`protocol(Socket client)` The method called as soon as a connection is established.
`void`	`run()` The run method of the receiver server.

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_RECEIVERNAME
```
public static final String KEY_RECEIVERNAME
```
    The key in the properties defining the name of this receiver.
    
    See Also:
    
    Constant Field Values
  - KEY_HOSTADDRESS
```
public static final String KEY_HOSTADDRESS
```
    The key to the host running the server. Null defers to local host.
    
    See Also:
    
    Constant Field Values
  - KEY_SERVERPORT
```
public static final String KEY_SERVERPORT
```
    The key for the socket port to listen to.
    
    See Also:
    
    Constant Field Values
  - KEY_BUFFERSIZE
```
public static final String KEY_BUFFERSIZE
```
    The key in the properties for the stream buffer size.
    
    See Also:
    
    Constant Field Values
  - KEY_SERVERPRIORITY
```
public static final String KEY_SERVERPRIORITY
```
    The key in the properties defining the priority of the server.
    
    See Also:
    
    Constant Field Values
  - KEY_HANDLERPRIORITY
```
public static final String KEY_HANDLERPRIORITY
```
    The key in the properties defining the priority of the server.
    
    See Also:
    
    Constant Field Values
  - KEY_LOGOUT
```
public static final String KEY_LOGOUT
```
    The key for the log-out time granted to the clients.
    
    See Also:
    
    Constant Field Values
  - DEFRECEIVERNAME
```
private static final String DEFRECEIVERNAME
```
    The default receiver (Receiver-).
    
    See Also:
    
    Constant Field Values
  - DEFSERVERPORT
```
public static final int DEFSERVERPORT
```
    The default port number (1026).
    
    See Also:
    
    Constant Field Values
  - DEFBUFFERSIZE
```
private static final int DEFBUFFERSIZE
```
    The default buffer size of the I/O streams (2048).
    
    See Also:
    
    Constant Field Values
  - DEFSERVERPRIORITY
```
private static final int DEFSERVERPRIORITY
```
    The default server thread priority (1).
    
    See Also:
    
    Constant Field Values
  - DEFHANDLERPRIORITY
```
private static final int DEFHANDLERPRIORITY
```
    The default handler thread priority (Thread.NORM_PRIORITY).
    
    See Also:
    
    Constant Field Values
  - DEFLOGOUT
```
private static final long DEFLOGOUT
```
    The default log-out time granted to clients.
    
    See Also:
    
    Constant Field Values
  - thisThread
```
private Thread thisThread
```
    A reference to the thread constructed from this Runnable.
  - listen
```
private ServerSocket listen
```
    The server socket the server listens to.
  - cancel
```
private boolean cancel
```
    Gets true if this thread should exit.
  - handlerGroup
```
protected final ThreadGroup handlerGroup
```
    The thread group handlers run in.
  - COUNT
```
private static int COUNT
```
    An internal counter for automatic naming.
- Constructor Detail
  - ReceiverServer
```
protected ReceiverServer(Map qualify)
```
    Constructs a new receiver with the specified properties. Use of this constructor ensures that following properties are defined (values in paranthesis are default values).
    - The receiver server listening port (1026).
    - The I/O-streams buffer size (2048).
    - The run-priority of the server (1).
    - The run-priority of the handler spawned when a connection is made (Thread.NORM_PRIORITY).
    - A name for the server (Receiver-<#>).
    Please be aware that relying on the auto-naming capabilities will almost always introduce naming confusions and should be avoided whenever possible.
- Method Detail
  - nextCount
```
private static int nextCount()
```
    Gets the next available number at automatic naming.
  - init
```
public void init()
```
    Initializes the receiver server. If timing is important, you can the escape pod with initReceiverServer().
    
    Specified by:
    
    init in interface Initializable
    
    Overrides:
    
    init in class CastingContainer
  - initReceiverServer
```
protected void initReceiverServer()
```
    An escape pod for subclasses. The init method sets the priority of the this thread. It must be called between construction and starting. This method does exactly the desired thing, it is called immediately after the construction of the receiver server.
  - getReceiverName
```
public String getReceiverName()
```
    Returns the name used for binding this receiver. The naming extensions from the caster abilities are stripped from the name.
    Note that each registered receiver must have a unique URL otherwise registering will replace the previous binding.
  - getServerPort
```
public int getServerPort()
```
    Returns the port number the clients should connect to on this receiver.
  - getBufferSize
```
public int getBufferSize()
```
    Returns the buffer size used for buffering the socket streams.
  - getServerPriority
```
public int getServerPriority()
```
    Returns the priority at which this thread (the server) should run.
  - getHandlerPriority
```
public int getHandlerPriority()
```
    Returns the priority at which the connection handler thread should run.
  - processError
```
public void processError(ErrorEvent ee)
```
    An escape pod for subclasses that want to do anything special with errors or exceptions thrown during the lifecycle of this thread. Note this is not a generic error or excaption handler. Its intention is to notify somebody of an error/exception message. The error/exception handling has to be done (prior) to this method call.
    The default implementation is empty.
    
    Specified by:
    
    processError in interface ErrorProcessing
    
    Parameters:
    
    thrown - The exception/error to be reported.
  - run
```
public void run()
```
    The run method of the receiver server. Unless cancel is called, it loops forever accepting connections. If a client connects to the listening port the server calls the abstract method protocol(java.net.Socket) that should in turn launch a dedicated helper thread and should return immediately.
    
    Specified by:
    
    run in interface Runnable
  - exit
```
public void exit()
```
    Closes the receiver socket.
    
    Specified by:
    
    exit in interface ExitCleaning
    
    Overrides:
    
    exit in class CastingContainer
  - protocol
```
protected abstract void protocol(Socket client)
```
    The method called as soon as a connection is established. Concrete subclasses should provide their own protocol here.
    
    Parameters:
    
    client - The client socket.
    
    See Also:
    
    CommandReceiver, ErrorReceiver
  - cancel
```
public void cancel()
```
    Cancels the server thread. It does so by calling the server sockets close method. This will provoke an I/O Exception to occur in the run() loop. This I/O Exception is catched and the cancel flag is querried within the catch. If it is true this thread exits gracefully.
    Note that this method blocks until the server thread is dead.
    
    Specified by:
    
    cancel in interface CancelRunnable
  - getAsociatedThread
```
public Thread getAsociatedThread()
```
    Returns the thread asociated with this server. Also used by daugther classes to determine the thread the server is running in
    
    Specified by:
    
    getAsociatedThread in interface CancelRunnable
  - maxTimeToCancel
```
public long maxTimeToCancel()
```
    Returns the maximum time-out for this thread. This is twice the log-out time.
    
    Specified by:
    
    maxTimeToCancel in interface CancelRunnable

Class ReceiverServer

Nested Class Summary

Nested classes/interfaces inherited from class util.PropertyResources

Field Summary

Fields inherited from class util.rmi.AbstractRmiCaster

Fields inherited from class util.PropertyResources

Fields inherited from class util.PropertyContainer

Fields inherited from interface util.ResourceSupplying

Fields inherited from interface util.PropertySupplying

Constructor Summary

Method Summary

Methods inherited from class stella.CastingContainer

Methods inherited from class util.rmi.AbstractRmiCaster

Methods inherited from class util.rmi.RmiPropertyContainer

Methods inherited from class util.PropertyResources

Methods inherited from class util.PropertyContainer

Methods inherited from class java.lang.Object

Methods inherited from interface util.PropertySupplying

Field Detail

KEY_RECEIVERNAME

KEY_HOSTADDRESS

KEY_SERVERPORT

KEY_BUFFERSIZE

KEY_SERVERPRIORITY

KEY_HANDLERPRIORITY

KEY_LOGOUT

DEFRECEIVERNAME

DEFSERVERPORT

DEFBUFFERSIZE

DEFSERVERPRIORITY

DEFHANDLERPRIORITY

DEFLOGOUT

thisThread

listen

cancel

handlerGroup

COUNT

Constructor Detail

ReceiverServer

Method Detail

nextCount

init

initReceiverServer

getReceiverName

getServerPort

getBufferSize

getServerPriority

getHandlerPriority

processError

run

exit

protocol

cancel

getAsociatedThread

maxTimeToCancel