/**
* Delete children from start to stop and replace with t even if t is a list (nil-root tree). num
* of children can increase or decrease. For huge child lists, inserting children can force
* walking rest of children to set their childindex; could be slow.
*/
public void replaceChildren(int startChildIndex, int stopChildIndex, Object t) {
/*
System.out.println("replaceChildren "+startChildIndex+", "+stopChildIndex+
" with "+((PythonTree)t).toStringTree());
System.out.println("in="+toStringTree());
*/
if (children == null) {
throw new IllegalArgumentException("indexes invalid; no children in list");
}
int replacingHowMany = stopChildIndex - startChildIndex + 1;
int replacingWithHowMany;
PythonTree newTree = (PythonTree) t;
List newChildren = null;
// normalize to a list of children to add: newChildren
if (newTree.isNil()) {
newChildren = newTree.children;
} else {
newChildren = new ArrayList(1);
newChildren.add(newTree);
}
replacingWithHowMany = newChildren.size();
int numNewChildren = newChildren.size();
int delta = replacingHowMany - replacingWithHowMany;
// if same number of nodes, do direct replace
if (delta == 0) {
int j = 0; // index into new children
for (int i = startChildIndex; i <= stopChildIndex; i++) {
PythonTree child = (PythonTree) newChildren.get(j);
children.set(i, child);
child.setParent(this);
child.setChildIndex(i);
j++;
}
} else if (delta > 0) { // fewer new nodes than there were
// set children and then delete extra
for (int j = 0; j < numNewChildren; j++) {
children.set(startChildIndex + j, newChildren.get(j));
}
int indexToDelete = startChildIndex + numNewChildren;
for (int c = indexToDelete; c <= stopChildIndex; c++) {
// delete same index, shifting everybody down each time
PythonTree killed = (PythonTree) children.remove(indexToDelete);
}
freshenParentAndChildIndexes(startChildIndex);
} else { // more new nodes than were there before
// fill in as many children as we can (replacingHowMany) w/o moving data
for (int j = 0; j < replacingHowMany; j++) {
children.set(startChildIndex + j, newChildren.get(j));
}
int numToInsert = replacingWithHowMany - replacingHowMany;
for (int j = replacingHowMany; j < replacingWithHowMany; j++) {
children.add(startChildIndex + j, newChildren.get(j));
}
freshenParentAndChildIndexes(startChildIndex);
}
// System.out.println("out="+toStringTree());
}
/** Set the parent and child index values for all child of t */
public void freshenParentAndChildIndexes() {
freshenParentAndChildIndexes(0);
}