/* An actor that retrieves the received properties of a connected port.
Copyright (c) 2004-2005 The Regents of the University of California.
All rights reserved.
Permission is hereby granted, without written agreement and without
license or royalty fees, to use, copy, modify, and distribute this
software and its documentation for any purpose, provided that the above
copyright notice and the following two paragraphs appear in all copies
of this software.
IN NO EVENT SHALL THE UNIVERSITY OF CALIFORNIA BE LIABLE TO ANY PARTY
FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF
THE UNIVERSITY OF CALIFORNIA HAS BEEN ADVISED OF THE POSSIBILITY OF
SUCH DAMAGE.
THE UNIVERSITY OF CALIFORNIA SPECIFICALLY DISCLAIMS ANY WARRANTIES,
INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE
PROVIDED HEREUNDER IS ON AN "AS IS" BASIS, AND THE UNIVERSITY OF
CALIFORNIA HAS NO OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT, UPDATES,
ENHANCEMENTS, OR MODIFICATIONS.
PT_COPYRIGHT_VERSION_2
COPYRIGHTENDKEY
*/
package ptolemy.domains.wireless.lib;
import java.util.Iterator;
import ptolemy.actor.IOPort;
import ptolemy.actor.TypedAtomicActor;
import ptolemy.actor.TypedIOPort;
import ptolemy.data.Token;
import ptolemy.data.expr.Parameter;
import ptolemy.data.type.BaseType;
import ptolemy.domains.wireless.kernel.AtomicWirelessChannel;
import ptolemy.domains.wireless.kernel.WirelessIOPort;
import ptolemy.kernel.CompositeEntity;
import ptolemy.kernel.Entity;
import ptolemy.kernel.util.IllegalActionException;
import ptolemy.kernel.util.NameDuplicationException;
//////////////////////////////////////////////////////////////////////////
//// GetProperties
/**
This actor retrieves the properties most recently received by
an input port that is connected on the inside to the trigger
port of this actor. That port
must be an instance of WirelessIOPort, and must be contained
by the container of this actor, or an exception will be thrown.
A typical usage pattern is inside an instance of WirelessComposite,
to connect the trigger input to the port from which you want to read
the properties.
<p>
NOTE: The type of the properties port is inferred from the
<i>defaultProperties</i> field of the channel used by the connected
port at preinitialize() time. If the connection is changed during
execution, or the connectivity is changed, then the type of the
port will not be updated, and a run-time type error could occur.
Thus, this actor assumes that these types do not change.
If the channel has no default properties (as in the base class
AtomicWirelessChannel), then the type of the properties port will
be undefined. If the output is left disconnected, then this is fine,
but if it is connected, then its type will need to be declared
explicitly.
@author Edward A. Lee
@version $Id$
@since Ptolemy II 4.0
@Pt.ProposedRating Green (cxh)
@Pt.AcceptedRating Yellow (cxh)
*/
public class GetProperties extends TypedAtomicActor {
/** Construct an actor with the specified container and name.
* @param container The container.
* @param name The name.
* @exception IllegalActionException If the entity cannot be contained
* by the proposed container.
* @exception NameDuplicationException If the container already has an
* actor with this name.
*/
public GetProperties(CompositeEntity container, String name)
throws NameDuplicationException, IllegalActionException {
super(container, name);
output = new TypedIOPort(this, "output", false, true);
// Create and configure the ports.
trigger = new TypedIOPort(this, "trigger", true, false);
_attachText("_iconDescription", "<svg>\n"
+ "<polygon points=\"-15,-15 15,15 15,-15 -15,15\" "
+ "style=\"fill:green\"/>\n" + "</svg>\n");
}
///////////////////////////////////////////////////////////////////
//// ports and parameters ////
/** Port that triggers execution.
*/
public TypedIOPort trigger;
/** Port that transmits the properties received on the <i>input</i>
* port.
*/
public TypedIOPort output;
///////////////////////////////////////////////////////////////////
//// public methods ////
/** Read the properties from the port connected to the trigger
* port and produce them at the output. If there are no properties,
* then produce no output.
* @exception IllegalActionException If the specified port is not
* an instance of WirelessIOPort, or if there is no such port.
*/
public void fire() throws IllegalActionException {
super.fire();
// Read and discard the input token.
if (trigger.hasToken(0)) {
/* Token inputValue = */trigger.get(0);
}
Iterator connectedPorts = trigger.sourcePortList().iterator();
while (connectedPorts.hasNext()) {
IOPort port = (IOPort) connectedPorts.next();
if (port.isInput() && port instanceof WirelessIOPort) {
// Found the port.
Token propertiesValue = ((WirelessIOPort) port)
.getProperties(0);
// Do not send properties if the port has no destinations.
// This prevents run-time type errors from occurring.
if ((propertiesValue != null) && (output.numberOfSinks() > 0)) {
output.send(0, propertiesValue);
}
return;
}
}
throw new IllegalActionException(this,
"Could not find a port to get properties from.");
}
/** Create receivers and set up the type constraints on the
* <i>output</i> port.
* @exception IllegalActionException If the base class throws it.
*/
public void preinitialize() throws IllegalActionException {
super.preinitialize();
// Disable default type inference.
output.setTypeEquals(BaseType.UNKNOWN);
Iterator connectedPorts = trigger.sourcePortList().iterator();
while (connectedPorts.hasNext()) {
IOPort port = (IOPort) connectedPorts.next();
if (port.isInput() && port instanceof WirelessIOPort) {
// Found the port.
Entity container = (Entity) (port.getContainer());
String channelName = ((WirelessIOPort) port).outsideChannel
.stringValue();
CompositeEntity container2 = (CompositeEntity) container
.getContainer();
if (container2 == null) {
throw new IllegalActionException(this,
"The container does not have a container.");
}
Entity channel = container2.getEntity(channelName);
if (channel instanceof AtomicWirelessChannel) {
Parameter channelProperties = ((AtomicWirelessChannel) channel).defaultProperties;
// Only set up the type constraint if the type of the
// of the properties field is known.
if (channelProperties.getType() != BaseType.UNKNOWN) {
output.setTypeSameAs(channelProperties);
}
} else {
throw new IllegalActionException(this,
"The connected port does not refer to a "
+ "valid channel.");
}
return;
}
}
throw new IllegalActionException(this,
"Could not find a port to get the type of the "
+ "properties from.");
}
}