/* A Wire with one trigger port that accepts read requests.
Copyright (c) 2006-2007 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.de.lib;
import ptolemy.data.Token;
import ptolemy.data.expr.Parameter;
import ptolemy.kernel.CompositeEntity;
import ptolemy.kernel.util.IllegalActionException;
import ptolemy.kernel.util.NameDuplicationException;
//////////////////////////////////////////////////////////////////////////
//// Wire
/**
A Wire is a stateful actor in DE. It should have an equal number
of input and output channels. If it receives input on <i>any</i> of
its channels, it will produce the most recent received on each
input channel to the corresponding output channel for <i>all</i>
channels. We can think its behavior similar to a wire in VHDL, where
the value is always the most recently received. If no input has been
received on an input channel, then the corresponding output channel
will get the value given by <i>initialValue</i>, possibly converted
to the type of the output. The type of the output is at least that
of the input and that of <i>initialValue</i>. Hence, for example,
if the input
is a double and <i>initialValue</i> is an int, then the output will
be a double.
@author Adam Cataldo, Edward A. Lee (contributor)
@version $Id$
@since Ptolemy II 5.2
@Pt.ProposedRating Red (acataldo)
@Pt.AcceptedRating Red (acataldo)
@see ptolemy.domains.de.lib.Sampler
@deprecated Use Sampler instead.
*/
public class Wire extends DETransformer {
/** Construct an actor with the given container and name.
* @param container The container.
* @param name The name of this actor.
* @exception IllegalActionException If the actor cannot be contained
* by the proposed container.
* @exception NameDuplicationException If the container already has an
* actor with this name.
*/
public Wire(CompositeEntity container, String name)
throws NameDuplicationException, IllegalActionException {
super(container, name);
input.setMultiport(true);
output.setMultiport(true);
output.setTypeAtLeast(input);
initialValue = new Parameter(this, "initialValue");
output.setTypeAtLeast(initialValue);
initialValue.setExpression("0");
_attachText("_iconDescription", "<svg>\n"
+ "<rect x=\"-20\" y=\"-20\" " + "width=\"40\" height=\"2\" "
+ "style=\"fill:black\"/>\n" + "<rect x=\"-20\" y=\"-10\" "
+ "width=\"40\" height=\"2\" " + "style=\"fill:black\"/>\n"
+ "<rect x=\"-20\" y=\"0\" " + "width=\"40\" height=\"2\" "
+ "style=\"fill:black\"/>\n" + "<rect x=\"-20\" y=\"10\" "
+ "width=\"40\" height=\"2\" " + "style=\"fill:black\"/>\n"
+ "</svg>\n");
}
///////////////////////////////////////////////////////////////////
//// ports and parameters ////
/** The value that is output when no input has yet been received
* on the corresponding channel. The output type at least the type
* of this parameter and the type of the input. The default value
* is 0 (an int).
*/
public Parameter initialValue;
///////////////////////////////////////////////////////////////////
//// public methods ////
/** If there is a token in on any channel of the <i>input</i> port,
* output the most recent value on all the <i>output</i> port
* channels.
* @exception IllegalActionException If the base class throws one.
*/
public void fire() throws IllegalActionException {
// Don't call "super.fire();", this actor extends another actor.
int inputWidth = input.getWidth();
int outputWidth = output.getWidth();
int commonWidth = Math.min(inputWidth, outputWidth);
// If the <i>initialValue</i> parameter was not set, or if the
// width of the input has changed.
if ((_lastInputs == null) || (_lastInputs.length != inputWidth)) {
_lastInputs = new Token[inputWidth];
Token defaultValue = initialValue.getToken();
for (int i = 0; i < inputWidth; i++) {
_lastInputs[i] = defaultValue;
}
}
for (int i = 0; i < commonWidth; i++) {
if (input.hasToken(i)) {
_lastInputs[i] = input.get(i);
}
output.send(i, _lastInputs[i]);
}
}
/** Initialize the actor.
* @exception IllegalActionException If the superclass throws it.
*/
public void initialize() throws IllegalActionException {
super.initialize();
_lastInputs = null;
}
/** Return true if there is any token on an input port.
* @exception IllegalActionException If the base class throws it.
*/
public boolean prefire() throws IllegalActionException {
boolean writeRequest = false;
int inputWidth = input.getWidth();
for (int i = 0; i < inputWidth; i++) {
writeRequest = writeRequest || input.hasToken(i);
}
return writeRequest || super.prefire();
}
///////////////////////////////////////////////////////////////////
//// private variables ////
/** The recorded inputs last seen. */
protected Token[] _lastInputs;
}