/* An up-down counter.
Copyright (c) 1998-2005 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
*/
//////////////////////////////////////////////////////////////////////////
//// Counter
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.IntToken;
import ptolemy.data.Token;
import ptolemy.data.type.BaseType;
import ptolemy.kernel.CompositeEntity;
import ptolemy.kernel.util.IllegalActionException;
import ptolemy.kernel.util.NameDuplicationException;
/**
* This actor implements an up-down counter of received tokens. Whenever
* a token is received from the <i>increment</i> input, the internal
* counter is incremented. Whenever a token is received from the
* <i>decrement</i> port, the internal counter is decremented. Whenever
* a token is received from either input port, a token is created on the
* output port with the integer value of the current count. At most one
* token will be consumed from each input during each firing. If a token
* is present on both input ports during any firing, then the increment
* and the decrement will cancel out, and only one output token will be
* produced.
* @author Steve Neuendorffer
* @version $Id$
* @since Ptolemy II 2.0
* @Pt.ProposedRating Yellow (neuendor)
* @Pt.AcceptedRating Yellow (neuendor)
*/
public class Counter extends TypedAtomicActor implements Rollbackable {
protected transient Checkpoint $CHECKPOINT = new Checkpoint(this);
///////////////////////////////////////////////////////////////////
//// ports and parameters ////
/**
* The increment port. If this input port
* receives a token, then the counter is incremented. The port
* has type general.
*/
public TypedIOPort increment;
/**
* The decrement port. If this input port
* receives a token, then the counter is decremented. The port
* has type general.
*/
public TypedIOPort decrement;
/**
* The output port with type IntToken.
*/
public TypedIOPort output;
///////////////////////////////////////////////////////////////////
//// public methods ////
// Check the increment port.
// Check the decrement port.
// Produce an output if we consumed an input.
///////////////////////////////////////////////////////////////////
//// private members ////
private int _count = 0;
private int _latestCount = 0;
private boolean _consumed;
/**
* 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 Counter(CompositeEntity container, String name) throws NameDuplicationException, IllegalActionException {
super(container, name);
increment = new TypedIOPort(this, "increment", true, false);
increment.setTypeEquals(BaseType.GENERAL);
decrement = new TypedIOPort(this, "decrement", true, false);
decrement.setTypeEquals(BaseType.GENERAL);
output = new TypedIOPort(this, "output", false, true);
output.setTypeEquals(BaseType.INT);
}
/**
* Consume at most one token from each input and update the
* counter appropriately. Send the current value of the counter
* to the output. If there are no input tokens available, no
* output will be produced. If a token is consumed from only the
* <i>increment</i> port the output value will be one more than
* the previous output value. If a token consumed from only the
* <i>decrement</i> port the output value will be one less than
* the previous output value. If a token is consumed from both
* input ports, then the output value will be the same as the
* previous output value. If the fire method is invoked multiple
* times in one iteration, then only the input read on the last
* invocation in the iteration will affect future outputs of the
* counter.
* @exception IllegalActionException If there is no director.
*/
public void fire() throws IllegalActionException {
super.fire();
$ASSIGN$_latestCount(_count);
$ASSIGN$_consumed(false);
for (int i = 0; i < increment.getWidth(); i++) {
if (increment.hasToken(i)) {
increment.get(i);
$ASSIGN$SPECIAL$_latestCount(11, _latestCount);
$ASSIGN$_consumed(true);
}
}
for (int i = 0; i < decrement.getWidth(); i++) {
if (decrement.hasToken(i)) {
decrement.get(i);
$ASSIGN$SPECIAL$_latestCount(12, _latestCount);
$ASSIGN$_consumed(true);
}
}
if (_consumed) {
Token out = new IntToken(_latestCount);
output.send(0, out);
}
}
/**
* Reset the count of inputs to zero.
* @exception IllegalActionException If the parent class throws it.
*/
public void initialize() throws IllegalActionException {
super.initialize();
$ASSIGN$_count(0);
}
/**
* Record the most recent output count as the actual count.
* @exception IllegalActionException If the base class throws it.
*/
public boolean postfire() throws IllegalActionException {
$ASSIGN$_count(_latestCount);
return super.postfire();
}
private final int $ASSIGN$_count(int newValue) {
if ($CHECKPOINT != null && $CHECKPOINT.getTimestamp() > 0) {
$RECORD$_count.add(null, _count, $CHECKPOINT.getTimestamp());
}
return _count = newValue;
}
private final int $ASSIGN$_latestCount(int newValue) {
if ($CHECKPOINT != null && $CHECKPOINT.getTimestamp() > 0) {
$RECORD$_latestCount.add(null, _latestCount, $CHECKPOINT.getTimestamp());
}
return _latestCount = newValue;
}
private final int $ASSIGN$SPECIAL$_latestCount(int operator, long newValue) {
if ($CHECKPOINT != null && $CHECKPOINT.getTimestamp() > 0) {
$RECORD$_latestCount.add(null, _latestCount, $CHECKPOINT.getTimestamp());
}
switch (operator) {
case 0:
return _latestCount += newValue;
case 1:
return _latestCount -= newValue;
case 2:
return _latestCount *= newValue;
case 3:
return _latestCount /= newValue;
case 4:
return _latestCount &= newValue;
case 5:
return _latestCount |= newValue;
case 6:
return _latestCount ^= newValue;
case 7:
return _latestCount %= newValue;
case 8:
return _latestCount <<= newValue;
case 9:
return _latestCount >>= newValue;
case 10:
return _latestCount >>>= newValue;
case 11:
return _latestCount++;
case 12:
return _latestCount--;
case 13:
return ++_latestCount;
case 14:
return --_latestCount;
default:
return _latestCount;
}
}
private final boolean $ASSIGN$_consumed(boolean newValue) {
if ($CHECKPOINT != null && $CHECKPOINT.getTimestamp() > 0) {
$RECORD$_consumed.add(null, _consumed, $CHECKPOINT.getTimestamp());
}
return _consumed = newValue;
}
public void $COMMIT(long timestamp) {
FieldRecord.commit($RECORDS, timestamp, $RECORD$$CHECKPOINT.getTopTimestamp());
$RECORD$$CHECKPOINT.commit(timestamp);
}
public void $RESTORE(long timestamp, boolean trim) {
_count = $RECORD$_count.restore(_count, timestamp, trim);
_latestCount = $RECORD$_latestCount.restore(_latestCount, timestamp, trim);
_consumed = $RECORD$_consumed.restore(_consumed, 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 $RECORD$_count = new FieldRecord(0);
private transient FieldRecord $RECORD$_latestCount = new FieldRecord(0);
private transient FieldRecord $RECORD$_consumed = new FieldRecord(0);
private transient FieldRecord[] $RECORDS = new FieldRecord[] {
$RECORD$_count,
$RECORD$_latestCount,
$RECORD$_consumed
};
}