/**
* Insert a link to the specified relation at the specified index, and notify the container by
* calling its connectionsChanged() method. This overrides the base class to allow inside links as
* well as links at the same level of the hierarchy.
*
* <p>The specified index can be any non-negative integer. Any links with indices larger than or
* equal to the one specified here will henceforth have indices that are larger by one. If the
* index is larger than the number of existing links (as returned by numLinks()), then empty links
* are inserted (these will be null elements in the list returned by linkedRelationsList() or in
* the enumeration returned by linkedRelations()). If the specified relation is null, then an
* empty outside link is inserted at the specified index.
*
* <p>Note that a port may be linked to the same relation more than once, in which case the link
* will be reported more than once by the linkedRelations() method.
*
* <p>In derived classes, the relation may be required to be an instance of a particular subclass
* of Relation (this is checked by the _checkLink() protected method).
*
* <p>This method is write-synchronized on the workspace and increments its version number.
*
* @param index The index at which to insert the link.
* @param relation The relation to link to this port.
* @exception IllegalActionException If the link would cross levels of the hierarchy, or the
* relation is incompatible, or the port has no container, or the port is not in the same
* workspace as the relation.
*/
@Override
public void insertLink(int index, Relation relation) throws IllegalActionException {
if (relation != null && _workspace != relation.workspace()) {
throw new IllegalActionException(
this, relation, "Cannot link because workspaces are different.");
}
try {
_workspace.getWriteAccess();
if (relation == null) {
// Assume outside link
_relationsList.insertLink(index, null);
} else {
_checkLink(relation);
if (_isInsideLinkable(relation.getContainer())) {
// An inside link
_insideLinks.insertLink(index, relation._linkList);
} else {
// An outside link
_relationsList.insertLink(index, relation._linkList);
}
}
// NOTE: _checkLink() ensures that the container is
// not null, and the class ensures that it is an Entity.
((Entity) getContainer()).connectionsChanged(this);
} finally {
_workspace.doneWriting();
}
}
/**
* Link this port with the specified relation. Note that a port may be linked to the same relation
* more than once, in which case the link will be reported more than once by the linkedRelations()
* method. If the argument is null, then create a null link (on the outside). This method is
* write-synchronized on the workspace and increments its version number.
*
* @param relation The relation to link to.
* @exception IllegalActionException If the link crosses levels of the hierarchy, or the port has
* no container, or the relation is not a ComponentRelation, or if the port is contained by a
* class definition.
*/
public void link(Relation relation) throws IllegalActionException {
if (relation != null) {
_checkLink(relation);
}
_doLink(relation);
}