package org.exist.storage.statistics;
import org.exist.Namespaces;
import org.exist.dom.QName;
import org.exist.dom.SymbolTable;
import org.exist.storage.NodePath;
import org.w3c.dom.Node;
import org.xml.sax.ContentHandler;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.AttributesImpl;
import java.nio.ByteBuffer;
import java.util.List;
/**
* Collects statistics for a single node in the data guide.
*/
class NodeStats {
private QName qname;
private int nodeCount = 0;
private int maxDepth = 0;
transient private int depth = 0;
protected NodeStats parent = null;
protected NodeStats[] children = null;
protected NodeStats(QName qname) {
this(null, qname);
}
protected NodeStats(NodeStats parent, QName qname) {
this.parent = parent;
this.qname = qname;
}
public void incDepth() {
this.depth++;
}
public void updateMaxDepth() {
if (depth > maxDepth)
{maxDepth = depth;}
depth = 0;
}
public int getMaxDepth() {
return maxDepth;
}
protected void addOccurrence() {
nodeCount++;
}
protected NodeStats addChild(QName qn) {
if (children != null) {
for (int i = 0; i < children.length; i++) {
final NodeStats child = children[i];
if (child.qname.equalsSimple(qn)) {
return child;
}
}
}
if (children == null) {
children = new NodeStats[1];
} else {
NodeStats[] tc = new NodeStats[children.length + 1];
System.arraycopy(children, 0, tc, 0, children.length);
children = tc;
}
children[children.length - 1] = new NodeStats(this, qn);
return children[children.length - 1];
}
protected void mergeInto(DataGuide other, NodePath currentPath) {
NodePath newPath;
if (qname == null)
{newPath = currentPath;}
else {
newPath = new NodePath(currentPath);
newPath.addComponent(qname);
other.add(newPath, this);
}
if (children != null) {
for (int i = 0; i < children.length; i++) {
final NodeStats child = children[i];
child.mergeInto(other, newPath);
}
}
}
protected void mergeStats(NodeStats other) {
nodeCount += other.nodeCount;
if (other.maxDepth > maxDepth)
{maxDepth = other.maxDepth;}
}
protected int getSize() {
int s = qname == null ? 0 : 1;
if (children != null) {
for (int i = 0; i < children.length; i++) {
s += children[i].getSize();
}
}
return s;
}
protected void getMaxParentDepth(QName name, NodeStats max) {
if (parent != null && qname != null && qname.equalsSimple(name)) {
max.maxDepth = Math.max(parent.maxDepth, max.maxDepth);
}
if (children != null) {
for (int i = 0; i < children.length; i++) {
children[i].getMaxParentDepth(name, max);
}
}
}
protected void write(ByteBuffer buffer, SymbolTable symbols) {
buffer.putShort(symbols.getNSSymbol(qname.getNamespaceURI()));
buffer.putShort(symbols.getSymbol(qname.getLocalName()));
buffer.putInt(nodeCount);
buffer.putInt(maxDepth);
buffer.putInt(children == null ? 0: children.length);
if (children != null) {
for (int i = 0; i < children.length; i++) {
children[i].write(buffer, symbols);
}
}
}
protected void read(ByteBuffer buffer, SymbolTable symbols) {
final short nsid = buffer.getShort();
final short localid = buffer.getShort();
final String namespaceURI = symbols.getNamespace(nsid);
final String localName = symbols.getName(localid);
qname = symbols.getQName(Node.ELEMENT_NODE, namespaceURI,
localName, "");
nodeCount = buffer.getInt();
maxDepth = buffer.getInt();
final int childCount = buffer.getInt();
if (childCount > 0) {
children = new NodeStats[childCount];
for (int i = 0; i < childCount; i++) {
children[i] = new NodeStats(this, null);
children[i].read(buffer, symbols);
}
}
}
protected void dump(StringBuilder currentPath, List<StringBuilder> paths) {
StringBuilder newPath;
if (qname == null)
{newPath = currentPath;}
else {
newPath = new StringBuilder(currentPath);
if (newPath.length() > 0)
{newPath.append(" -> ");}
newPath.append(qname);
newPath.append('[').append(nodeCount).append(',');
newPath.append(maxDepth).append(']');
}
paths.add(newPath);
if (children != null) {
for (int i = 0; i < children.length; i++) {
final NodeStats child = children[i];
child.dump(newPath, paths);
}
}
}
public void toSAX(ContentHandler handler) throws SAXException {
final AttributesImpl attribs = new AttributesImpl();
attribs.addAttribute("", "name", "name", "CDATA", qname.getLocalName());
attribs.addAttribute("", "namespace", "namespace", "CDATA", qname.getNamespaceURI());
attribs.addAttribute("", "node-count", "node-count", "CDATA", Integer.toString(nodeCount));
attribs.addAttribute("", "max-depth", "max-depth", "CDATA", Integer.toString(maxDepth));
handler.startElement(Namespaces.EXIST_NS, "node", "node", attribs);
if (children != null) {
for (int i = 0; i < children.length; i++) {
children[i].toSAX(handler);
}
}
handler.endElement(Namespaces.EXIST_NS, "node", "node");
}
}