Program: 72694
Project: 72694
Buggy source:
/** 
 * Evaluate the expression and send its result to the output.
 * @exception IllegalActionException If the evaluation of the expressiontriggers it, or the evaluation yields a null result, or the evaluation yields an incompatible type, or if there is no director.
 */
public void fire() throws IllegalActionException {
  super.fire();
  Director director=getDirector();
  if (director == null) {
    throw new IllegalActionException(this,"String_Node_Str");
  }
synchronized (Engine.semaphore) {
    matlabEngine.evalString(engine,"String_Node_Str");
    if (_addPathCommand != null) {
      matlabEngine.evalString(engine,_addPathCommand);
    }
    try {
      matlabEngine.put(engine,"String_Node_Str",new DoubleToken(director.getModelTime().getDoubleValue()));
    }
 catch (    IllegalActionException ex) {
      throw new IllegalActionException(this,ex,"String_Node_Str" + "String_Node_Str" + new DoubleToken(director.getModelTime().getDoubleValue()));
    }
    try {
      matlabEngine.put(engine,"String_Node_Str",_iteration.getToken());
    }
 catch (    IllegalActionException ex) {
      throw new IllegalActionException(this,ex,"String_Node_Str" + "String_Node_Str" + _iteration.getToken());
    }
    Iterator inputPorts=inputPortList().iterator();
    while (inputPorts.hasNext()) {
      IOPort port=(IOPort)inputPorts.next();
      matlabEngine.put(engine,port.getName(),port.get(0));
    }
    matlabEngine.evalString(engine,expression.stringValue());
    Iterator outputPorts=outputPortList().iterator();
    while (outputPorts.hasNext()) {
      IOPort port=(IOPort)outputPorts.next();
      if (port.isOutsideConnected()) {
        port.send(0,matlabEngine.get(engine,port.getName(),_dataParameters));
      }
    }
    if (_previousPath != null) {
      matlabEngine.put(engine,"String_Node_Str",_previousPath);
      matlabEngine.evalString(engine,"String_Node_Str");
    }
  }
}

Fixed version (ground truth):
/** 
 * Evaluate the expression and send its result to the output.
 * @exception IllegalActionException If the evaluation of the expressiontriggers it, or the evaluation yields a null result, or the evaluation yields an incompatible type, or if there is no director.
 */
public void fire() throws IllegalActionException {
  super.fire();
  Director director=getDirector();
  if (director == null) {
    throw new IllegalActionException(this,"String_Node_Str");
  }
  try {
    for (    TypedIOPort port : inputPortList()) {
      _inputTokens.put(port.getName(),port.get(0));
    }
synchronized (Engine.semaphore) {
      matlabEngine.evalString(engine,"String_Node_Str");
      if (_addPathCommand != null) {
        matlabEngine.evalString(engine,_addPathCommand);
      }
      try {
        matlabEngine.put(engine,"String_Node_Str",new DoubleToken(director.getModelTime().getDoubleValue()));
      }
 catch (      IllegalActionException ex) {
        throw new IllegalActionException(this,ex,"String_Node_Str" + "String_Node_Str" + new DoubleToken(director.getModelTime().getDoubleValue()));
      }
      try {
        matlabEngine.put(engine,"String_Node_Str",_iteration.getToken());
      }
 catch (      IllegalActionException ex) {
        throw new IllegalActionException(this,ex,"String_Node_Str" + "String_Node_Str" + _iteration.getToken());
      }
      for (      Map.Entry<String,Token> entry : _inputTokens.entrySet()) {
        matlabEngine.put(engine,entry.getKey(),entry.getValue());
      }
      matlabEngine.evalString(engine,expression.stringValue());
      Iterator outputPorts=outputPortList().iterator();
      while (outputPorts.hasNext()) {
        IOPort port=(IOPort)outputPorts.next();
        if (port.isOutsideConnected()) {
          port.send(0,matlabEngine.get(engine,port.getName(),_dataParameters));
        }
      }
      if (_previousPath != null) {
        matlabEngine.put(engine,"String_Node_Str",_previousPath);
        matlabEngine.evalString(engine,"String_Node_Str");
      }
    }
  }
  finally {
    _inputTokens.clear();
  }
}