org.refcodes.connection.ext.observable.ObservableConnectionSenderImpl Maven / Gradle / Ivy
Show all versions of refcodes-io-ext-observable Show documentation
// /////////////////////////////////////////////////////////////////////////////
// REFCODES.ORG
// =============================================================================
// This code is copyright (c) by Siegfried Steiner, Munich, Germany and licensed
// under the following (see "http://en.wikipedia.org/wiki/Multi-licensing")
// licenses:
// =============================================================================
// GNU General Public License, v3.0 ("http://www.gnu.org/licenses/gpl-3.0.html")
// together with the GPL linking exception applied; as being applied by the GNU
// Classpath ("http://www.gnu.org/software/classpath/license.html")
// =============================================================================
// Apache License, v2.0 ("http://www.apache.org/licenses/LICENSE-2.0")
// =============================================================================
// Please contact the copyright holding author(s) of the software artifacts in
// question for licensing issues not being covered by the above listed licenses,
// also regarding commercial licensing models or regarding the compatibility
// with other open source licenses.
// /////////////////////////////////////////////////////////////////////////////
package org.refcodes.connection.ext.observable;
import java.io.Serializable;
import java.util.concurrent.ExecutorService;
import org.refcodes.component.CloseException;
import org.refcodes.component.ConnectionStatus;
import org.refcodes.component.OpenException;
import org.refcodes.component.ext.observer.ClosedEvent;
import org.refcodes.component.ext.observer.ConnectionObserver;
import org.refcodes.component.ext.observer.OpenedEvent;
import org.refcodes.controlflow.ExecutionStrategy;
import org.refcodes.exception.VetoException;
import org.refcodes.io.ConnectionSender;
import org.refcodes.mixin.Loggable;
import org.refcodes.observer.AbstractObservable;
import org.refcodes.observer.ActionMetaDataEvent;
import org.refcodes.observer.EventMetaData;
import org.refcodes.observer.EventMetaDataImpl;
import org.refcodes.observer.GenericActionEvent;
/**
* The {@link ObservableConnectionSenderImpl} implements the
* {@link ObservableConnectionSender} for wrapping and extending a
* {@link ConnectionSender} with observable functionality.
*
* TODO: Test cases are to be created!
*
* @param The type of the datagram to be operated with.
* @param The type of the connection to be used.
*/
public class ObservableConnectionSenderImpl implements ObservableConnectionSender, Loggable {
// /////////////////////////////////////////////////////////////////////////
// CONSTANTS:
// /////////////////////////////////////////////////////////////////////////
// /////////////////////////////////////////////////////////////////////////
// VARIABLES:
// /////////////////////////////////////////////////////////////////////////
private ConnectionSender _connectionSender;
private ConnectionObservable _observable;
private EventMetaData _eventMetaData;
private Object _source;
private boolean _isDestroyed = false;
// /////////////////////////////////////////////////////////////////////////
// CONSTRUCTORS:
// /////////////////////////////////////////////////////////////////////////
/**
* Constructs a {@link ObservableConnectionSenderImpl} with the given
* attributes.
*
* @param aConnectionSender The {@link ConnectionSender} to which the
* connection method calls are to be delegated to.
*/
public ObservableConnectionSenderImpl( ConnectionSender aConnectionSender ) {
_connectionSender = aConnectionSender;
_eventMetaData = new EventMetaDataImpl( this.getClass() );
_source = this;
_observable = new ConnectionObservable();
}
/**
* Constructs a {@link ObservableConnectionSenderImpl} with the given
* attributes.
*
* @param aConnectionSender The {@link ConnectionSender} to which the
* connection method calls are to be delegated to.
*
* @param aSource The source instance to be used when firing events in case
* the source is to be different from this class' instance.
*/
public ObservableConnectionSenderImpl( ConnectionSender aConnectionSender, Object aSource ) {
_connectionSender = aConnectionSender;
_eventMetaData = new EventMetaDataImpl( this.getClass() );
_source = aSource;
_observable = new ConnectionObservable();
}
/**
* Constructs a {@link ObservableConnectionSenderImpl} with the given
* attributes.
*
* @param aConnectionSender The {@link ConnectionSender} to which the
* connection method calls are to be delegated to.
*
* @param aEventMetaData The {@link EventMetaData} to be used when firing
* events in case the {@link EventMetaData} is to be different from
* the auto-generated {@link EventMetaData}.
*/
public ObservableConnectionSenderImpl( ConnectionSender aConnectionSender, EventMetaData aEventMetaData ) {
_connectionSender = aConnectionSender;
_eventMetaData = aEventMetaData;
_source = this;
_observable = new ConnectionObservable();
}
/**
* Constructs a {@link ObservableConnectionSenderImpl} with the given
* attributes.
*
* @param aConnectionSender The {@link ConnectionSender} to which the
* connection method calls are to be delegated to.
*
* @param aEventMetaData The {@link EventMetaData} to be used when firing
* events in case the {@link EventMetaData} is to be different from
* the auto-generated {@link EventMetaData}.
*
* @param aSource The source instance to be used when firing events in case
* the source is to be different from this class' instance.
*/
public ObservableConnectionSenderImpl( ConnectionSender aConnectionSender, EventMetaData aEventMetaData, Object aSource ) {
_connectionSender = aConnectionSender;
_eventMetaData = aEventMetaData;
_source = aSource;
_observable = new ConnectionObservable();
}
// WITH EXECUTOR-SERVICE:
/**
* Constructs a {@link ObservableConnectionSenderImpl} with the given
* attributes.
*
* @param aConnectionSender The {@link ConnectionSender} to which the
* connection method calls are to be delegated to.
*
* @param aExecutorService The executor service to be used when firing
* {@link GenericActionEvent} instances in multiple threads (if null
* then a default one is used).
*
* @param aExecutionStrategy The {@link ExecutionStrategy} to be used when
* firing {@link GenericActionEvent} instance (if null then the
* default {@link ExecutionStrategy#SEQUENTIAL} is used).
*/
public ObservableConnectionSenderImpl( ConnectionSender aConnectionSender, ExecutorService aExecutorService, ExecutionStrategy aExecutionStrategy ) {
_connectionSender = aConnectionSender;
_eventMetaData = new EventMetaDataImpl( this.getClass() );
_source = this;
_observable = new ConnectionObservable( aExecutorService, aExecutionStrategy );
}
/**
* Constructs a {@link ObservableConnectionSenderImpl} with the given
* attributes.
*
* @param aConnectionSender The {@link ConnectionSender} to which the
* connection method calls are to be delegated to.
*
* @param aSource The source instance to be used when firing events in case
* the source is to be different from this class' instance.
*
* @param aExecutorService The executor service to be used when firing
* {@link GenericActionEvent} instances in multiple threads (if null
* then a default one is used).
*
* @param aExecutionStrategy The {@link ExecutionStrategy} to be used when
* firing {@link GenericActionEvent} instance (if null then the
* default {@link ExecutionStrategy#SEQUENTIAL} is used).
*/
public ObservableConnectionSenderImpl( ConnectionSender aConnectionSender, Object aSource, ExecutorService aExecutorService, ExecutionStrategy aExecutionStrategy ) {
_connectionSender = aConnectionSender;
_eventMetaData = new EventMetaDataImpl( this.getClass() );
_source = aSource;
_observable = new ConnectionObservable( aExecutorService, aExecutionStrategy );
}
/**
* Constructs a {@link ObservableConnectionSenderImpl} with the given
* attributes.
*
* @param aConnectionSender The {@link ConnectionSender} to which the
* connection method calls are to be delegated to.
*
* @param aEventMetaData The {@link EventMetaData} to be used when firing
* events in case the {@link EventMetaData} is to be different from
* the auto-generated {@link EventMetaData}.
*
* @param aExecutorService The executor service to be used when firing
* {@link GenericActionEvent} instances in multiple threads (if null
* then a default one is used).
*
* @param aExecutionStrategy The {@link ExecutionStrategy} to be used when
* firing {@link GenericActionEvent} instance (if null then the
* default {@link ExecutionStrategy#SEQUENTIAL} is used).
*/
public ObservableConnectionSenderImpl( ConnectionSender aConnectionSender, EventMetaData aEventMetaData, ExecutorService aExecutorService, ExecutionStrategy aExecutionStrategy ) {
_connectionSender = aConnectionSender;
_eventMetaData = aEventMetaData;
_source = this;
_observable = new ConnectionObservable( aExecutorService, aExecutionStrategy );
}
/**
* Constructs a {@link ObservableConnectionSenderImpl} with the given
* attributes.
*
* @param aConnectionSender The {@link ConnectionSender} to which the
* connection method calls are to be delegated to.
*
* @param aEventMetaData The {@link EventMetaData} to be used when firing
* events in case the {@link EventMetaData} is to be different from
* the auto-generated {@link EventMetaData}.
*
* @param aSource The source instance to be used when firing events in case
* the source is to be different from this class' instance.
*
* @param aExecutorService The executor service to be used when firing
* {@link GenericActionEvent} instances in multiple threads (if null
* then a default one is used).
*
* @param aExecutionStrategy The {@link ExecutionStrategy} to be used when
* firing {@link GenericActionEvent} instance (if null then the
* default {@link ExecutionStrategy#SEQUENTIAL} is used).
*/
public ObservableConnectionSenderImpl( ConnectionSender aConnectionSender, EventMetaData aEventMetaData, Object aSource, ExecutorService aExecutorService, ExecutionStrategy aExecutionStrategy ) {
_connectionSender = aConnectionSender;
_eventMetaData = aEventMetaData;
_source = aSource;
_observable = new ConnectionObservable( aExecutorService, aExecutionStrategy );
}
// /////////////////////////////////////////////////////////////////////////
// METHODS:
// /////////////////////////////////////////////////////////////////////////
/**
* {@inheritDoc}
*/
@Override
public boolean isClosed() {
return _connectionSender.isClosed();
}
/**
* {@inheritDoc}
*/
@Override
public boolean isOpened() {
return _connectionSender.isOpened();
}
/**
* {@inheritDoc}
*/
@Override
public ConnectionStatus getConnectionStatus() {
return _connectionSender.getConnectionStatus();
}
/**
* {@inheritDoc}
*/
@Override
public void flush() throws OpenException {
_connectionSender.flush();
}
/**
* {@inheritDoc}
*/
@Override
public void close() throws CloseException {
_connectionSender.close();
try {
_observable.fireEvent( new ClosedEvent( _eventMetaData, _source ) );
}
catch ( VetoException e ) {
/* Cannot happen here */
}
}
/**
* {@inheritDoc}
*/
@Override
public void open( CON aConnection ) throws OpenException {
_connectionSender.open( aConnection );
try {
_observable.fireEvent( new OpenedEvent( _eventMetaData, _source ) );
}
catch ( VetoException e ) {
/* Cannot happen here */
}
}
/**
* {@inheritDoc}
*/
@Override
public void writeDatagram( DATA aDatagram ) throws OpenException {
_connectionSender.writeDatagram( aDatagram );
}
/**
* {@inheritDoc}
*/
@Override
public boolean isClosable() {
return _connectionSender.isClosable();
}
/**
* {@inheritDoc}
*/
@Override
public boolean isOpenable( CON aConnection ) {
return _connectionSender.isOpenable( aConnection );
}
// /////////////////////////////////////////////////////////////////////////
// OBSERVERS:
// /////////////////////////////////////////////////////////////////////////
/**
* {@inheritDoc}
*/
@Override
public boolean hasObserverSubscription( ConnectionObserver aObserver ) {
return _observable.hasObserverSubscription( aObserver );
}
/**
* {@inheritDoc}
*/
@Override
public boolean subscribeObserver( ConnectionObserver aObserver ) {
return _observable.subscribeObserver( aObserver );
}
/**
* {@inheritDoc}
*/
@Override
public boolean unsubscribeObserver( ConnectionObserver aObserver ) {
return _observable.unsubscribeObserver( aObserver );
}
// /////////////////////////////////////////////////////////////////////////
// COMPONENT:
// /////////////////////////////////////////////////////////////////////////
/**
* {@inheritDoc}
*/
@Override
public void destroy() {
if ( !_isDestroyed ) {
_isDestroyed = true;
try {
close();
}
catch ( CloseException e ) {
warn( "Unable to close malfunctioning connection.", e );
}
_connectionSender = null;
_observable.clear();
_observable = null;
_source = null;
_eventMetaData = null;
}
}
// /////////////////////////////////////////////////////////////////////////
// HOOKS:
// /////////////////////////////////////////////////////////////////////////
// /////////////////////////////////////////////////////////////////////////
// HELPER:
// /////////////////////////////////////////////////////////////////////////
// /////////////////////////////////////////////////////////////////////////
// INNER CLASSES:
// /////////////////////////////////////////////////////////////////////////
/**
* The {@link ConnectionObservable} extends the {@link AbstractObservable}
* to make the using class {@link GenericActionEvent} aware.
*/
private class ConnectionObservable extends AbstractObservable {
// /////////////////////////////////////////////////////////////////////
// VARIABLES:
// /////////////////////////////////////////////////////////////////////
private ExecutionStrategy _executionStrategy;
// /////////////////////////////////////////////////////////////////////
// CONSTRUCTORS:
// /////////////////////////////////////////////////////////////////////
/**
* Instantiates a new connection observable.
*/
public ConnectionObservable() {
super();
_executionStrategy = ExecutionStrategy.SEQUENTIAL;
}
/**
* Instantiates a new connection observable.
*
* @param aExecutorService the executor service
* @param aExecutionStrategy the execution strategy
*/
public ConnectionObservable( ExecutorService aExecutorService, ExecutionStrategy aExecutionStrategy ) {
super( aExecutorService );
_executionStrategy = (aExecutionStrategy != null) ? aExecutionStrategy : ExecutionStrategy.SEQUENTIAL;
}
// /////////////////////////////////////////////////////////////////////
// METHODS:
// /////////////////////////////////////////////////////////////////////
/**
* {@inheritDoc}
*/
@Override
public int size() {
return super.size();
}
/**
* {@inheritDoc}
*/
@Override
public boolean isEmpty() {
return super.isEmpty();
}
/**
* {@inheritDoc}
*/
@Override
public void clear() {
super.clear();
}
// /////////////////////////////////////////////////////////////////////
// HOOKS:
// /////////////////////////////////////////////////////////////////////
/**
* Same as {@link #fireEvent(MetaDataEvent, ExecutionStrategy)} with
* a predefined {@link ExecutionStrategy#JOIN}.
*
* @param aEvent the event
* @return true, if successful
* @throws VetoException the veto exception
* @see #fireEvent(MetaDataEvent, ExecutionStrategy)
*/
protected boolean fireEvent( ActionMetaDataEvent aEvent ) throws VetoException {
return super.fireEvent( aEvent, _executionStrategy );
}
/**
* {@inheritDoc}
*/
@Override
protected boolean fireEvent( ActionMetaDataEvent aEvent, ConnectionObserver aObserver, ExecutionStrategy aExecutionStrategy ) throws VetoException {
if ( aEvent instanceof OpenedEvent ) {
aObserver.onOpendEvent( (OpenedEvent) aEvent );
}
else if ( aEvent instanceof ClosedEvent ) {
aObserver.onClosedEvent( (ClosedEvent) aEvent );
}
aObserver.onEvent( aEvent );
return true;
}
}
}