/**
* Deletes a node and its descendants.
*
* @param pre pre value of the node to delete
*/
public final void delete(final int pre) {
meta.update();
// size of the subtree to delete
int k = kind(pre);
final int s = size(pre, k);
resources.delete(pre, s);
if (meta.updindex) {
// delete child records from indexes
indexDelete(pre, s);
}
/// explicitly delete text or attribute value
if (k != DOC && k != ELEM) delete(pre, k != ATTR);
// reduce size of ancestors
int par = pre;
// check if we are an attribute (different size counters)
if (k == ATTR) {
par = parent(par, ATTR);
attSize(par, ELEM, attSize(par, ELEM) - 1);
size(par, ELEM, size(par, ELEM) - 1);
k = kind(par);
}
// reduce size of ancestors
while (par > 0 && k != DOC) {
par = parent(par, k);
k = kind(par);
size(par, k, size(par, k) - s);
}
// preserve empty root node
if (kind(pre) == DOC) --meta.ndocs;
if (meta.updindex) {
// delete node and descendants from ID -> PRE map:
idmap.delete(pre, id(pre), -s);
}
// delete node from table structure and reduce document size
table.delete(pre, s);
if (!cache) updateDist(pre, -s);
// propagate PRE value shifts to namespaces
nspaces.delete(pre, s, this);
}
/**
* Returns the value for the specified pre value.
*
* @param pre pre value
* @return item value
*/
byte[] getValue(final int pre) {
final Data data = plotData.context.data;
final int limit = pre + data.size(pre, Data.ELEM);
for (int p = pre; p < limit; ++p) {
final int kind = data.kind(p);
if ((kind == Data.ELEM && tag || kind == Data.ATTR && !tag) && attrID == data.name(p))
return data.atom(p);
}
return EMPTY;
}
/**
* Creates an item iterator for the given XML fragment.
*
* @param xml fragment
* @param frag fragment flag
* @return iterator
*/
private ItemCache toIter(final String xml, final boolean frag) {
final ItemCache it = new ItemCache();
try {
String str = frag ? "<X>" + xml + "</X>" : xml;
final Data d = CreateDB.xml(IO.get(str), context);
for (int p = frag ? 2 : 0; p < d.meta.size; p += d.size(p, d.kind(p)))
it.add(new DBNode(d, p));
} catch (final IOException ex) {
return new ItemCache(new Item[] {Str.get(Long.toString(System.nanoTime()))}, 1);
}
return it;
}
/**
* Finds the closest namespace node for the specified pre value.
*
* @param pre pre value
* @param data data reference
* @return node
*/
NSNode find(final int pre, final Data data) {
final int s = find(pre);
// no match found: return current node
if (s == -1) return this;
final NSNode ch = children[s];
final int cp = ch.pr;
// return exact hit
if (cp == pre) return ch;
// found node is preceding sibling
if (cp + data.size(cp, Data.ELEM) <= pre) return this;
// continue recursive search
return children[s].find(pre, data);
}
/**
* Lists resources of the specified database.
*
* @return success flag
* @throws IOException I/O exception
*/
private boolean listDB() throws IOException {
final String db = args[0];
final String path = args[1] != null ? args[1] : "";
if (!Databases.validName(db)) return error(NAME_INVALID_X, db);
final Table table = new Table();
table.description = RESOURCES;
table.header.add(INPUT_PATH);
table.header.add(TYPE);
table.header.add(MimeTypes.CONTENT_TYPE);
table.header.add(SIZE);
try {
// add xml documents
final Data data = Open.open(db, context);
final Resources res = data.resources;
final IntList il = res.docs(path);
final int ds = il.size();
for (int i = 0; i < ds; i++) {
final int pre = il.get(i);
final TokenList tl = new TokenList(3);
final byte[] file = data.text(pre, true);
tl.add(file);
tl.add(DataText.M_XML);
tl.add(MimeTypes.APP_XML);
tl.add(data.size(pre, Data.DOC));
table.contents.add(tl);
}
// add binary resources
for (final byte[] file : res.binaries(path)) {
final String f = string(file);
final TokenList tl = new TokenList(3);
tl.add(file);
tl.add(DataText.M_RAW);
tl.add(MimeTypes.get(f));
tl.add(data.meta.binary(f).length());
table.contents.add(tl);
}
Close.close(data, context);
} catch (final IOException ex) {
return error(Util.message(ex));
}
out.println(table.sort().finish());
return true;
}
/**
* Updates distances to restore parent-child relationships that have been invalidated by
* structural updates.
*
* <p>Each structural update (insert/delete) leads to a shift of higher PRE values. This
* invalidates parent-child relationships. Distances are only updated after all structural updates
* have been carried out to make sure each node (that has to be updated) is only touched once.
*/
public void updateDistances() {
accumulatePreValueShifts();
final IntSet alreadyUpdatedNodes = new IntSet();
for (final BasicUpdate update : updStructural) {
int newPreOfAffectedNode = update.preOfAffectedNode + update.accumulatedShifts;
/* Update distance for the affected node and all following siblings of nodes
* on the ancestor-or-self axis. */
while (newPreOfAffectedNode < data.meta.size) {
if (alreadyUpdatedNodes.contains(newPreOfAffectedNode)) break;
data.dist(
newPreOfAffectedNode,
data.kind(newPreOfAffectedNode),
calculateNewDistance(newPreOfAffectedNode));
alreadyUpdatedNodes.add(newPreOfAffectedNode);
newPreOfAffectedNode += data.size(newPreOfAffectedNode, data.kind(newPreOfAffectedNode));
}
}
}
/**
* Removes superfluous update operations. If a node T is deleted or replaced, all updates on the
* descendant axis of T can be left out as they won't affect the database after all.
*
* <p>Superfluous updates can have a minimum PRE value of pre(T)+1 and a maximum PRE value of
* pre(T)+size(T).
*
* <p>An update with location pre(T)+size(T) can only be removed if the update is an atomic insert
* and the inserted node is then part of the subtree of T.
*/
public void optimize() {
if (opt) return;
check();
// traverse from lowest to highest PRE value
int i = updStructural.size() - 1;
while (i >= 0) {
final BasicUpdate u = updStructural.get(i);
// If this update can lead to superfluous updates ...
if (u.destructive()) {
// we determine the lowest and highest PRE values of a superfluous update
final int pre = u.location;
final int fol = pre + data.size(pre, data.kind(pre));
i--;
// and have a look at the next candidate
while (i >= 0) {
final BasicUpdate desc = updStructural.get(i);
final int descpre = desc.location;
// if the candidate operates on the subtree of T and inserts a node ...
if (descpre <= fol
&& (desc instanceof Insert || desc instanceof InsertAttr)
&& desc.parent() >= pre
&& desc.parent() < fol) {
// it is removed.
updStructural.remove(i--);
// Other updates (not inserting a node) that operate on the subtree of T can
// only have a PRE value that is smaller than the following PRE of T
} else if (descpre < fol) {
// these we delete.
updStructural.remove(i--);
// Else there's nothing to delete
} else break;
}
} else i--;
}
opt = true;
}
/**
* Writes the entry for the specified pre value to the table.
*
* @param t table reference
* @param data data reference
* @param p node to be printed
*/
private static void table(final Table t, final Data data, final int p) {
final int k = data.kind(p);
final TokenList tl = new TokenList();
tl.add(p);
tl.add(p - data.parent(p, k));
tl.add(data.size(p, k));
tl.add(data.attSize(p, k));
final int u = data.uri(p, k);
if (data.nsFlag(p)) tl.add("+" + u);
else tl.add(u);
tl.add(TABLEKINDS[k]);
byte[] cont = null;
if (k == Data.ELEM) {
cont = data.name(p, k);
} else if (k == Data.ATTR) {
cont =
new TokenBuilder(data.name(p, k)).add(ATT1).add(data.text(p, false)).add(ATT2).finish();
} else {
cont = data.text(p, true);
}
tl.add(replace(chop(cont, 64), '\n', ' '));
t.contents.add(tl);
}
/**
* Inserts a data instance at the specified pre value. Note that the specified data instance must
* differ from this instance.
*
* @param ipre value at which to insert new data
* @param ipar parent pre value of node
* @param clip data clip
*/
public final void insert(final int ipre, final int ipar, final DataClip clip) {
meta.update();
// update value and document indexes
if (meta.updindex) indexBegin();
resources.insert(ipre, clip);
final int dsize = clip.size();
final int buf = Math.min(dsize, IO.BLOCKSIZE >> IO.NODEPOWER);
// resize buffer to cache more entries
buffer(buf);
// find all namespaces in scope to avoid duplicate declarations
final TokenMap nsScope = nspaces.scope(ipar, this);
// loop through all entries
final IntList preStack = new IntList();
final NSNode nsRoot = nspaces.current();
final HashSet<NSNode> newNodes = new HashSet<NSNode>();
final IntList flagPres = new IntList();
// indicates if database only contains a dummy node
final Data data = clip.data;
int c = 0;
for (int dpre = clip.start; dpre < clip.end; ++dpre, ++c) {
if (c != 0 && c % buf == 0) insert(ipre + c - buf);
final int pre = ipre + c;
final int dkind = data.kind(dpre);
final int dpar = data.parent(dpre, dkind);
// ipar < 0 if document nodes on top level are added
final int dis = dpar >= 0 ? dpre - dpar : ipar >= 0 ? pre - ipar : 0;
final int par = dis == 0 ? -1 : pre - dis;
if (c == 0) nspaces.root(par, this);
while (!preStack.isEmpty() && preStack.peek() > par) nspaces.close(preStack.pop());
switch (dkind) {
case DOC:
// add document
nspaces.prepare();
final int s = data.size(dpre, dkind);
doc(pre, s, data.text(dpre, true));
meta.ndocs++;
preStack.push(pre);
break;
case ELEM:
// add element
nspaces.prepare();
boolean ne = false;
if (data.nsFlag(dpre)) {
final Atts at = data.ns(dpre);
for (int a = 0; a < at.size(); ++a) {
// see if prefix has been declared/ is part of current ns scope
final byte[] old = nsScope.get(at.name(a));
if (old == null || !eq(old, at.value(a))) {
// we have to keep track of all new NSNodes that are added
// to the Namespace structure, as their pre values must not
// be updated. I.e. if an NSNode N with pre value 3 existed
// prior to inserting and two new nodes are inserted at
// location pre == 3 we have to make sure N and only N gets
// updated.
newNodes.add(nspaces.add(at.name(a), at.value(a), pre));
ne = true;
}
}
}
byte[] nm = data.name(dpre, dkind);
elem(
dis,
tagindex.index(nm, null, false),
data.attSize(dpre, dkind),
data.size(dpre, dkind),
nspaces.uri(nm, true),
ne);
preStack.push(pre);
break;
case TEXT:
case COMM:
case PI:
// add text
text(pre, dis, data.text(dpre, true), dkind);
break;
case ATTR:
// add attribute
nm = data.name(dpre, dkind);
// check if prefix already in nsScope or not
final byte[] attPref = prefix(nm);
// check if prefix of attribute has already been declared, otherwise
// add declaration to parent node
if (data.nsFlag(dpre) && nsScope.get(attPref) == null) {
nspaces.add(
par,
preStack.isEmpty() ? -1 : preStack.peek(),
attPref,
data.nspaces.uri(data.uri(dpre, dkind)),
this);
// save pre value to set ns flag later for this node. can't be done
// here as direct table access would interfere with the buffer
flagPres.add(par);
}
attr(
pre,
dis,
atnindex.index(nm, null, false),
data.text(dpre, false),
nspaces.uri(nm, false),
false);
break;
}
}
// finalize and update namespace structure
while (!preStack.isEmpty()) nspaces.close(preStack.pop());
nspaces.root(nsRoot);
if (bp != 0) insert(ipre + c - 1 - (c - 1) % buf);
// reset buffer to old size
buffer(1);
// set ns flags
for (int f = 0; f < flagPres.size(); f++) {
final int fl = flagPres.get(f);
table.write2(fl, 1, name(fl) | 1 << 15);
}
// increase size of ancestors
int p = ipar;
while (p >= 0) {
final int k = kind(p);
size(p, k, size(p, k) + dsize);
p = parent(p, k);
}
if (meta.updindex) {
// add the entries to the ID -> PRE mapping:
idmap.insert(ipre, id(ipre), dsize);
indexEnd();
}
if (!cache) updateDist(ipre + dsize, dsize);
// propagate PRE value shifts to namespaces
if (ipar != -1) nspaces.insert(ipre, dsize, newNodes);
}
/**
* Replaces parts of the database with the specified data instance.
*
* @param rpre pre value to be replaced
* @param clip data clip
*/
public final void replace(final int rpre, final DataClip clip) {
meta.update();
final int dsize = clip.size();
final Data data = clip.data;
final int rkind = kind(rpre);
final int rsize = size(rpre, rkind);
final int rpar = parent(rpre, rkind);
final int diff = dsize - rsize;
buffer(dsize);
resources.replace(rpre, rsize, clip);
if (meta.updindex) {
// update index
indexDelete(rpre, rsize);
indexBegin();
}
for (int dpre = clip.start; dpre < clip.end; ++dpre) {
final int dkind = data.kind(dpre);
final int dpar = data.parent(dpre, dkind);
final int pre = rpre + dpre - clip.start;
final int dis = dpar >= 0 ? dpre - dpar : pre - rpar;
switch (dkind) {
case DOC:
// add document
doc(pre, data.size(dpre, dkind), data.text(dpre, true));
meta.ndocs++;
break;
case ELEM:
// add element
byte[] nm = data.name(dpre, dkind);
elem(
dis,
tagindex.index(nm, null, false),
data.attSize(dpre, dkind),
data.size(dpre, dkind),
nspaces.uri(nm, true),
false);
break;
case TEXT:
case COMM:
case PI:
// add text
text(pre, dis, data.text(dpre, true), dkind);
break;
case ATTR:
// add attribute
nm = data.name(dpre, dkind);
attr(
pre,
dis,
atnindex.index(nm, null, false),
data.text(dpre, false),
nspaces.uri(nm, false),
false);
break;
}
}
if (meta.updindex) {
indexEnd();
// update ID -> PRE map:
idmap.delete(rpre, id(rpre), -rsize);
idmap.insert(rpre, meta.lastid - dsize + 1, dsize);
}
// update table:
table.replace(rpre, buffer(), rsize);
buffer(1);
// no distance/size update if the two subtrees are of equal size
if (diff == 0) return;
// increase/decrease size of ancestors, adjust distances of siblings
int p = rpar;
while (p >= 0) {
final int k = kind(p);
size(p, k, size(p, k) + diff);
p = parent(p, k);
}
if (!cache) updateDist(rpre + dsize, diff);
// adjust attribute size of parent if attributes inserted. attribute size
// of parent cannot be reduced via a replace expression.
int dpre = clip.start;
if (data.kind(dpre) == ATTR) {
int d = 0;
while (dpre < clip.end && data.kind(dpre++) == ATTR) d++;
if (d > 1) attSize(rpar, kind(rpar), d + 1);
}
}
/**
* Returns the pre value of the next child.
*
* @return next child reference
*/
int next() {
final int p = pre;
pre += data.size(pre, data.kind(pre));
return p;
}
/**
* Initializes the iterator.
*
* @param p root pre value
*/
private void init(final int p) {
final int k = data.kind(p);
size = p + data.size(p, k);
pre = p + data.attSize(p, k);
}
/**
* Adds a replace atomic to the list.
*
* @param pre PRE value of the target node/update location
* @param d insertion sequence data reference
*/
public void addReplace(final int pre, final Data d) {
final int oldsize = data.size(pre, data.kind(pre));
final int newsize = d.meta.size;
add(new Replace(pre, newsize - oldsize, pre + oldsize, d), true);
}
/**
* Adds a delete atomic to the list.
*
* @param pre PRE value of the target node/update location
*/
public void addDelete(final int pre) {
final int k = data.kind(pre);
final int s = data.size(pre, k);
add(new Delete(pre, -s, pre + s), true);
}