IndexTreeRebuilder.java

package thaw.plugins;

import java.util.Vector;
import java.util.Iterator;

import thaw.core.Core;
import thaw.core.Logger;
import thaw.core.Plugin;
import thaw.core.ThawThread;
import thaw.core.ThawRunnable;
import thaw.core.I18n;
import thaw.gui.WarningWindow;

import thaw.plugins.Hsqldb;


import java.sql.*;


public class IndexTreeRebuilder implements Plugin {
	private Core core;
	private Hsqldb db;

	public IndexTreeRebuilder() {
	}


	private class Rebuilder implements ThawRunnable {
		private boolean running;
		private Plugin parent;

		public Rebuilder(Plugin parent) {
			running = true;
			this.parent = parent;
		}

		private void rebuildIndex(Vector parents, int indexId) throws SQLException {

			PreparedStatement st =
				db.getConnection().prepareStatement("INSERT INTO indexParents "+
								    "(indexId, folderId) "+
								    "VALUES (?, ?)");

			for (Iterator it = parents.iterator();
			     it.hasNext();) {
				st.setInt(1, indexId);

				int parent = ((Integer)it.next()).intValue();

				if (parent >= 0)
					st.setInt(2, parent);
				else
					st.setNull(2, Types.INTEGER);

				st.execute();
			}
			
			st.close();
		}


		/**
		 * rebuild == rebuild the content of indexParents and folderParents
		 * @param parents Integer vector (id of the parent folders)
		 */
		private void rebuild(Vector parents, int folderId) throws SQLException {

			Vector newParentsVector = new Vector(parents);
			newParentsVector.add(new Integer(folderId));

			PreparedStatement st;

			/* rebuild all the indexes in the subfolders */

			String where = ((folderId >= 0) ?
					"WHERE parent = ?" :
					"WHERE parent IS NULL");

			st = db.getConnection().prepareStatement("SELECT id FROM indexFolders "+where);

			if (folderId >= 0)
				st.setInt(1, folderId);

			ResultSet set = st.executeQuery();

			while(set.next()) {
				rebuild(newParentsVector, set.getInt("id"));
			}

			st.close();

			/* rebuild all the indexes in this folder */

			st = db.getConnection().prepareStatement("SELECT id FROM indexes "+where);

			if (folderId >= 0)
				st.setInt(1, folderId);

			set = st.executeQuery();

			while(set.next()) {
				rebuildIndex(newParentsVector, set.getInt("id"));
			}

			st.close();

			/* rebuild this folder */

			st = db.getConnection().prepareStatement("INSERT INTO folderParents "+
								 "(folderId, parentId) "+
								 "VALUES (?, ?)");

			for (Iterator it = parents.iterator();
			     it.hasNext();) {
				if (folderId >= 0)
					st.setInt(1, folderId);
				else
					st.setNull(1, Types.INTEGER);

				int parent = ((Integer)it.next()).intValue();

				if (parent >= 0)
					st.setInt(2, parent);
				else
					st.setNull(2, Types.INTEGER);

				st.execute();
			}

			st.close();
		}

		/**
		 * Take the db lock before calling this function !
		 */
		public void rebuild() throws SQLException {

			/* quick & dirty, as usual */
			PreparedStatement st =
				db.getConnection().prepareStatement("DELETE FROM indexParents");
			st.execute();

			st = db.getConnection().prepareStatement("DELETE FROM folderParents");
			st.execute();
			
			st.close();

			rebuild(new Vector(), -1);

		}


		public void run() {

			if(core.getPluginManager().getPlugin("thaw.plugins.Hsqldb") == null) {
				Logger.info(this, "Loading Hsqldb plugin");

				if(core.getPluginManager().loadPlugin("thaw.plugins.Hsqldb") == null
				   || !core.getPluginManager().runPlugin("thaw.plugins.Hsqldb")) {
					Logger.error(this, "Unable to load thaw.plugins.Hsqldb !");
					return;
				}
			}

			db = (Hsqldb)core.getPluginManager().getPlugin("thaw.plugins.Hsqldb");

			if (db == null) {
				Logger.error(this, "Can't access the db !");
			} else {

				db.registerChild(parent);

				if (running)
					core.getPluginManager().stopPlugin("thaw.plugins.IndexBrowser");

				if (running) {
					try {
						synchronized(db.dbLock) {
							rebuild();
						}
					} catch(SQLException e) {
						/* wow, getting creepy */
						Logger.error(this, "Index tree rebuild failed : "+e.toString());
						new WarningWindow(core,
								  I18n.getMessage("thaw.plugin.index.treeRebuilder.failed"));
					}
				}

				if (running)
				new WarningWindow(core,
						  I18n.getMessage("thaw.plugin.index.treeRebuilder.finished"));

				if (running)
					core.getPluginManager().runPlugin("thaw.plugins.IndexBrowser");

				db.unregisterChild(parent);
			}

			core.getPluginManager().stopPlugin("thaw.plugins.IndexTreeRebuilder");
			core.getPluginManager().unloadPlugin("thaw.plugins.IndexTreeRebuilder");

			core.getConfigWindow().getPluginConfigPanel().refreshList();
		}

		public void stop() {
			running = false;
		}
	}


	public boolean run(Core core) {
		this.core = core;

		ThawThread th = new ThawThread(new Rebuilder(this),
					       "Index tree rebuilder",
					       this);
		th.start();

		return true;
	}

	public void stop() {

	}

	public String getNameForUser() {
		return I18n.getMessage("thaw.plugin.index.treeRebuilder");
	}

	public javax.swing.ImageIcon getIcon() {
		return null;
	}
}