/**
* get the ancestor based on level, level = 0, means itself. if level is out of the boundary, just
* return the toppest one
*
* @param level
* @return it will never return null.
*/
public CourseComponent getAncestor(int level) {
if (parent == null || level == 0) return this;
IBlock root = parent;
while (level != 0 && root.getParent() != null) {
root = root.getParent();
level--;
}
return (CourseComponent) root;
}
/** get ancestor with give blockType, starting from itself */
public CourseComponent getAncestor(EnumSet<BlockType> types) {
if (types.contains(type)) return this;
IBlock ancestor = parent;
if (ancestor == null) return null;
do {
if (types.contains(ancestor.getType())) return (CourseComponent) ancestor;
} while ((ancestor = ancestor.getParent()) != null);
return null;
}
