/* A source of a sequence of events.
Copyright (c) 2004-2007 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
*/
//////////////////////////////////////////////////////////////////////////
//// Sequence
package ptolemy.backtrack.automatic.ptolemy.actor.lib;
import java.lang.Object;
import ptolemy.actor.TypedAtomicActor;
import ptolemy.actor.TypedIOPort;
import ptolemy.backtrack.Checkpoint;
import ptolemy.backtrack.Rollbackable;
import ptolemy.backtrack.util.CheckpointRecord;
import ptolemy.backtrack.util.FieldRecord;
import ptolemy.data.ArrayToken;
import ptolemy.data.BooleanToken;
import ptolemy.data.expr.Parameter;
import ptolemy.data.type.ArrayType;
import ptolemy.data.type.BaseType;
import ptolemy.kernel.CompositeEntity;
import ptolemy.kernel.util.IllegalActionException;
import ptolemy.kernel.util.InternalErrorException;
import ptolemy.kernel.util.NameDuplicationException;
import ptolemy.kernel.util.Workspace;
/**
* This actor produces a sequence of values, optionally periodically repeating
* them. The <i>values</i> parameter contains an ArrayToken that specifies the
* sequence of values to produce at the output. If the <i>enable</i> input
* port is connected, then it provides a boolean sequence that specifies
* whether to produce an output. If the <i>enable</i> is present and
* true, then the actor will produce the next output. Otherwise, it
* produces no output and will produce the next in the sequence
* on the next firing (if enable is true). If the <i>holdLastOutput</i>
* parameter is true, then the sequence is infinite, with the last
* value being repeated forever.
* <p>
* Compared with the Pulse actor, this actor can be enabled or disabled
* on each firing by providing a true or false input on the <i>enable</i>
* port.
* @author Edward A. Lee
* @version $Id$
* @since Ptolemy II 4.1
* @see Pulse
* @Pt.ProposedRating Yellow (eal)
* @Pt.AcceptedRating Red (cxh)
*/
public class Sequence extends TypedAtomicActor implements Rollbackable {
protected transient Checkpoint $CHECKPOINT = new Checkpoint(this);
// set values parameter
// Set the Repeat Flag.
// set type constraint
///////////////////////////////////////////////////////////////////
//// ports and parameters ////
/**
* The enable input port. If this port is connected, then its
* input will determine whether an output is produced in any
* given firing. The type is boolean.
*/
public TypedIOPort enable;
/**
* A flag indicating whether to interpret the <i>values</i>
* as an infinite sequence where the last value is repeated
* forever. This is a boolean that defaults to false.
*/
public Parameter holdLastOutput;
/**
* The output port. The type is greater than or equal to the
* types of the two input ports.
*/
public TypedIOPort output;
/**
* The flag that indicates whether the sequence needs to be
* repeated. If this is false, then either the last value of the
* sequence is repeatedly produced after the entire sequence
* has been produced, or the actor stops producing output,
* depending on the value of <i>holdLastOutput</i>.
* This is a boolean, and defaults to false.
*/
public Parameter repeat;
/**
* The values that will be produced on the output.
* This parameter is an array, with default value {1}.
*/
public Parameter values;
///////////////////////////////////////////////////////////////////
//// public methods ////
// Note that this will default to null if there is no initialValue set.
// To repeatedly produce the last output.
// To prevent overflow.
// No more outputs to produce.
///////////////////////////////////////////////////////////////////
//// private variables ////
// The index of the next value to be produced.
// Indicator that an output was produced.
private int _currentIndex;
private boolean _outputProduced;
/**
* Construct an actor in the specified container with the specified
* name.
* @param container The container.
* @param name The name of this actor within the container.
* @exception IllegalActionException If the actor cannot be contained
* by the proposed container.
* @exception NameDuplicationException If the name coincides with
* an actor already in the container.
*/
public Sequence(CompositeEntity container, String name) throws IllegalActionException, NameDuplicationException {
super(container, name);
values = new Parameter(this, "values");
values.setExpression("{1}");
repeat = new Parameter(this, "repeat", BooleanToken.FALSE);
repeat.setTypeEquals(BaseType.BOOLEAN);
holdLastOutput = new Parameter(this, "holdLastOutput", BooleanToken.FALSE);
holdLastOutput.setTypeEquals(BaseType.BOOLEAN);
enable = new TypedIOPort(this, "enable", true, false);
enable.setTypeEquals(BaseType.BOOLEAN);
output = new TypedIOPort(this, "output", false, true);
output.setTypeAtLeast(ArrayType.elementType(values));
}
/**
* Clone the actor into the specified workspace. This overrides the
* base class to handle type constraints.
* @param workspace The workspace for the new object.
* @return A new actor.
* @exception CloneNotSupportedException If a derived class contains
* an attribute that cannot be cloned.
*/
public Object clone(Workspace workspace) throws CloneNotSupportedException {
Sequence newObject = (Sequence)super.clone(workspace);
try {
newObject.output.setTypeAtLeast(ArrayType.elementType(newObject.values));
} catch (IllegalActionException e) {
throw new InternalErrorException(e);
}
return newObject;
}
/**
* If the <i>enable</i> input is connected, then if it has a true
* token, produce the next output. If it is not connected, produce
* the next output unconditionally. Whether it is connected is
* determined by checking the width of the port.
* @exception IllegalActionException If there is no director.
*/
public void fire() throws IllegalActionException {
super.fire();
if ((!enable.isOutsideConnected()) || (enable.hasToken(0) && ((BooleanToken)enable.get(0)).booleanValue())) {
ArrayToken valuesArray = (ArrayToken)values.getToken();
if (_currentIndex < valuesArray.length()) {
output.send(0, valuesArray.getElement(_currentIndex));
$ASSIGN$_outputProduced(true);
}
}
}
/**
* Initialize the actor by resetting to the first output value.
* @exception IllegalActionException If there is no director.
*/
public void initialize() throws IllegalActionException {
$ASSIGN$_currentIndex(0);
$ASSIGN$_outputProduced(false);
super.initialize();
}
/**
* Update the state of the actor by moving to the next value
* in the <i>values</i> array.
* @exception IllegalActionException If there is no director.
*/
public boolean postfire() throws IllegalActionException {
boolean result = super.postfire();
if (_outputProduced) {
$ASSIGN$_outputProduced(false);
$ASSIGN$SPECIAL$_currentIndex(0, 1);
ArrayToken valuesArray = (ArrayToken)values.getToken();
if (_currentIndex >= valuesArray.length()) {
boolean repeatValue = ((BooleanToken)repeat.getToken()).booleanValue();
if (repeatValue) {
$ASSIGN$_currentIndex(0);
} else {
boolean holdLastOutputValue = ((BooleanToken)holdLastOutput.getToken()).booleanValue();
if (holdLastOutputValue) {
$ASSIGN$_currentIndex(valuesArray.length() - 1);
} else {
$ASSIGN$_currentIndex(valuesArray.length());
result = false;
}
}
}
}
return result;
}
private final int $ASSIGN$_currentIndex(int newValue) {
if ($CHECKPOINT != null && $CHECKPOINT.getTimestamp() > 0) {
$RECORD$_currentIndex.add(null, _currentIndex, $CHECKPOINT.getTimestamp());
}
return _currentIndex = newValue;
}
private final int $ASSIGN$SPECIAL$_currentIndex(int operator, long newValue) {
if ($CHECKPOINT != null && $CHECKPOINT.getTimestamp() > 0) {
$RECORD$_currentIndex.add(null, _currentIndex, $CHECKPOINT.getTimestamp());
}
switch (operator) {
case 0:
return _currentIndex += newValue;
case 1:
return _currentIndex -= newValue;
case 2:
return _currentIndex *= newValue;
case 3:
return _currentIndex /= newValue;
case 4:
return _currentIndex &= newValue;
case 5:
return _currentIndex |= newValue;
case 6:
return _currentIndex ^= newValue;
case 7:
return _currentIndex %= newValue;
case 8:
return _currentIndex <<= newValue;
case 9:
return _currentIndex >>= newValue;
case 10:
return _currentIndex >>>= newValue;
case 11:
return _currentIndex++;
case 12:
return _currentIndex--;
case 13:
return ++_currentIndex;
case 14:
return --_currentIndex;
default:
return _currentIndex;
}
}
private final boolean $ASSIGN$_outputProduced(boolean newValue) {
if ($CHECKPOINT != null && $CHECKPOINT.getTimestamp() > 0) {
$RECORD$_outputProduced.add(null, _outputProduced, $CHECKPOINT.getTimestamp());
}
return _outputProduced = newValue;
}
public void $COMMIT(long timestamp) {
FieldRecord.commit($RECORDS, timestamp, $RECORD$$CHECKPOINT.getTopTimestamp());
$RECORD$$CHECKPOINT.commit(timestamp);
}
public void $RESTORE(long timestamp, boolean trim) {
_currentIndex = $RECORD$_currentIndex.restore(_currentIndex, timestamp, trim);
_outputProduced = $RECORD$_outputProduced.restore(_outputProduced, timestamp, trim);
if (timestamp <= $RECORD$$CHECKPOINT.getTopTimestamp()) {
$CHECKPOINT = $RECORD$$CHECKPOINT.restore($CHECKPOINT, this, timestamp, trim);
FieldRecord.popState($RECORDS);
$RESTORE(timestamp, trim);
}
}
public final Checkpoint $GET$CHECKPOINT() {
return $CHECKPOINT;
}
public final Object $SET$CHECKPOINT(Checkpoint checkpoint) {
if ($CHECKPOINT != checkpoint) {
Checkpoint oldCheckpoint = $CHECKPOINT;
if (checkpoint != null) {
$RECORD$$CHECKPOINT.add($CHECKPOINT, checkpoint.getTimestamp());
FieldRecord.pushState($RECORDS);
}
$CHECKPOINT = checkpoint;
oldCheckpoint.setCheckpoint(checkpoint);
checkpoint.addObject(this);
}
return this;
}
protected transient CheckpointRecord $RECORD$$CHECKPOINT = new CheckpointRecord();
private transient FieldRecord $RECORD$_currentIndex = new FieldRecord(0);
private transient FieldRecord $RECORD$_outputProduced = new FieldRecord(0);
private transient FieldRecord[] $RECORDS = new FieldRecord[] {
$RECORD$_currentIndex,
$RECORD$_outputProduced
};
}