/**
* 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());
}
public void setChild(int i, PythonTree t) {
if (t == null) {
return;
}
if (t.isNil()) {
throw new IllegalArgumentException("Can't set single child to a list");
}
if (children == null) {
children = createChildrenList();
}
children.set(i, t);
t.setParent(this);
t.setChildIndex(i);
}
/**
* Add t as child of this node.
*
* <p>Warning: if t has no children, but child does and child isNil then this routine moves
* children to t via t.children = child.children; i.e., without copying the array.
*/
public void addChild(PythonTree t) {
// System.out.println("add child "+t.toStringTree()+" "+this.toStringTree());
// System.out.println("existing children: "+children);
if (t == null) {
return; // do nothing upon addChild(null)
}
PythonTree childTree = (PythonTree) t;
if (childTree.isNil()) { // t is an empty node possibly with children
if (this.children != null && this.children == childTree.children) {
throw new RuntimeException("attempt to add child list to itself");
}
// just add all of childTree's children to this
if (childTree.children != null) {
if (this.children != null) { // must copy, this has children already
int n = childTree.children.size();
for (int i = 0; i < n; i++) {
PythonTree c = (PythonTree) childTree.children.get(i);
this.children.add(c);
// handle double-link stuff for each child of nil root
c.setParent(this);
c.setChildIndex(children.size() - 1);
}
} else {
// no children for this but t has children; just set pointer
// call general freshener routine
this.children = childTree.children;
this.freshenParentAndChildIndexes();
}
}
} else { // child is not nil (don't care about children)
if (children == null) {
children = createChildrenList(); // create children list on demand
}
children.add(t);
childTree.setParent(this);
childTree.setChildIndex(children.size() - 1);
}
// System.out.println("now children are: "+children);
}
