/**
* Specify the container entity, adding the relation to the list of relations in the container. If
* the container already contains a relation with the same name, then throw an exception and do
* not make any changes. Similarly, if the container is not in the same workspace as this
* relation, throw an exception. If the relation is a class element and the proposed container
* does not match the current container, then also throw an exception. If the relation is already
* contained by the container, do nothing. If this relation already has a container, remove it
* from that container first. Otherwise, remove it from the workspace directory, if it is present.
* If the argument is null, then unlink the ports from the relation and remove it from its
* container. It is not added to the workspace directory, so this could result in this relation
* being garbage collected. Derived classes may further constrain the class of the container to a
* subclass of CompositeEntity. This method validates all deeply contained instances of Settable,
* since they may no longer be valid in the new context. This method is write-synchronized on the
* workspace and increments its version number.
*
* @param container The proposed container.
* @exception IllegalActionException If this entity and the container are not in the same
* workspace, or if a contained Settable becomes invalid and the error handler throws it.
* @exception NameDuplicationException If the name collides with a name already on the contents
* list of the container.
* @see #getContainer()
*/
public void setContainer(CompositeEntity container)
throws IllegalActionException, NameDuplicationException {
if ((container != null) && (_workspace != container.workspace())) {
throw new IllegalActionException(
this, container, "Cannot set container because workspaces are different.");
}
try {
_workspace.getWriteAccess();
_checkContainer(container);
CompositeEntity previousContainer = (CompositeEntity) getContainer();
if (previousContainer == container) {
return;
}
// Do this first, because it may throw an exception.
if (container != null) {
container._addRelation(this);
if (previousContainer == null) {
_workspace.remove(this);
}
}
_container = container;
if (previousContainer != null) {
previousContainer._removeRelation(this);
}
if (container == null) {
unlinkAll();
} else {
// We have successfully set a new container for this
// object. Mark it modified to ensure MoML export.
// Transfer any queued change requests to the
// new container. There could be queued change
// requests if this component is deferring change
// requests.
if (_changeRequests != null) {
Iterator requests = _changeRequests.iterator();
while (requests.hasNext()) {
ChangeRequest request = (ChangeRequest) requests.next();
container.requestChange(request);
}
_changeRequests = null;
}
}
// Validate all deeply contained settables, since
// they may no longer be valid in the new context.
validateSettables();
} finally {
_workspace.doneWriting();
}
}
