genericsqlsource.java

jcrontab是一个定时器开源项目包 目前提供存取文件或数据库, 把执行结果寄发 email, 简单地设置在 Tomcat, Resin, Jetty 及 JBoss 之上, 更是可以取代 cron

/**
 *  This file is part of the jcrontab package
 *  Copyright (C) 2001-2003 Israel Olalla
 *
 *  This library is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU Lesser General Public
 *  License as published by the Free Software Foundation; either
 *  version 2 of the License, or (at your option) any later version.
 *
 *  This library is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 *  Lesser General Public License for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public
 *  License along with this library; if not, write to the Free
 *  Software Foundation, Inc., 59 Temple Place, Suite 330, Boston,
 *  MA 02111-1307, USA
 *
 *  For questions, suggestions:
 *
 *  [e-mail]
 *
 */

package org.jcrontab.data;

import java.sql.Connection;
import java.sql.Driver;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.util.Vector;
import javax.naming.Context;
import javax.naming.InitialContext;
import javax.naming.NameNotFoundException;
import javax.naming.NamingException;
import org.jcrontab.Crontab;
import org.jcrontab.log.Log;

/**
 * This class is only a generic example and doesn't aim to solve all the needs
 * for the differents system's. if you want to make this class to fit your needs
 * feel free to do it and remember the license.
 * On of the things this class does is to open a connection to the database
 * , this is nasty and very expensive, y you want to integrate jcrontab with a 
 * pool like poolman or jboss it's quite easy, should substitute connection logic
 * with particular one.
 * @author $Author: iolalla $
 * @version $Revision: 1.37 $
 */
public class GenericSQLSource implements DataSource {
	
	private CrontabParser cp = new CrontabParser();

    /** This is the database driver being used. */
    private static Object dbDriver = null;
    private static GenericSQLSource instance;
    
    /** This Query gets all the Crontab entries from the
     * events table
     */    
    public static String queryAll = "SELECT id, second, minute, hour, dayofmonth, "
                                    + " month,"
                                    + " dayofweek, "
                                    + " year, task, extrainfo, businessDays "
                                    + " FROM events";
    /** This Query gets all the Crontab entries from the
     * events table but searching by the name
     */    
    public static String querySearching = "SELECT id, second, minute, hour, "
                                    + " dayofmonth, month,"
                                    + " dayofweek, "
                                    + " year, task, extrainfo, businessDays "
                                    + " FROM events" 
                                    + " WHERE task = ? ";
    /** This Query stores the Crontab entries
     */    
    public static String queryStoring = "INSERT INTO events("
                                    + " id, second, minute, hour, dayofmonth,"
                                    + " month, dayofweek, year, "
                                    + " task, extrainfo, businessDays) "
                                    + " VALUES(?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)";

    /** This Query removes the given Crontab Entries
     */    
    public static String queryRemoving = "DELETE FROM events WHERE "
                                      + " id = ? ";

	/** This Query finds the next value in the sequence 
     */
    public static String nextSequence = "SELECT MAX(id) id FROM EVENTS " ;
    
    /** Creates new GenericSQLSource */
	
    protected GenericSQLSource() {
    }	

    /** This method grants this class to be a singleton
     * and grants data access integrity
     * @return returns the instance
     */    
    public DataSource getInstance() {
		if (instance == null) {
		    instance = new GenericSQLSource();
		}
		return instance;
    }
    
    /**
     *  This method searches the Crontab Entry that the class has the given name
     *  @param CrontabEntryBean bean this method only lets store an 
     * entryBean each time.
     *  @throws CrontabEntryException when it can't parse the line correctly
     *  @throws ClassNotFoundException cause loading the driver can throw an
     *  ClassNotFoundException
     *  @throws SQLException Yep can throw an SQLException too
     */ 
    public CrontabEntryBean find(CrontabEntryBean ceb) throws  CrontabEntryException, 
                            ClassNotFoundException, SQLException, DataNotFoundException {
	CrontabEntryBean[] cebra = findAll();
		for (int i = 0; i < cebra.length ; i++) {
			if (cebra[i].equals(ceb)) {
				return cebra[i];
			}
		}
		throw new DataNotFoundException("Unable to find :" + ceb);
    }
    
    /**
     *  This method searches all the CrontabEntries from the DataSource
     *  @return CrontabEntryBean[] the array of CrontabEntryBeans.
     *  @throws CrontabEntryException when it can't parse the line correctly
     *  @throws ClassNotFoundException cause loading the driver can throw an
     *  ClassNotFoundException
     *  @throws SQLException Yep can throw an SQLException too
     */
    public CrontabEntryBean[] findAll() throws  CrontabEntryException, 
                            ClassNotFoundException, SQLException, DataNotFoundException {
                                
        Vector list = new Vector();

		Connection conn = null;
		java.sql.Statement st = null;
		java.sql.ResultSet rs = null;
		try {
		    conn = getConnection();
		    st = conn.createStatement();
		    rs = st.executeQuery(queryAll);
		    if(rs!=null) {
			while(rs.next()) {
                boolean[] bSeconds = new boolean[60];
                boolean[] bYears = new boolean[10];
                int id = rs.getInt("id");
                String second = rs.getString("second");
			    String minute = rs.getString("minute");
			    String hour = rs.getString("hour");
			    String dayofmonth = rs.getString("dayofmonth");
			    String month = rs.getString("month");
			    String dayofweek = rs.getString("dayofweek");
                String year = rs.getString("year");
			    String task = rs.getString("task");
			    String extrainfo = rs.getString("extrainfo");
			    String line = minute + " " + hour + " " + dayofmonth 
				+ " " + month + " " 
				+ dayofweek + " " + task + " " + extrainfo;
                
                String sBusinessDays = rs.getString("businessDays");
                boolean businessDays = false ;
                if (sBusinessDays != null && 
                                    sBusinessDays.equalsIgnoreCase("true")) {
                    businessDays = true ;
                }
                
			    CrontabEntryBean ceb = cp.marshall(line);
                
                cp.parseToken(year, bYears, false);
                ceb.setId(id);
                ceb.setBYears(bYears);
                ceb.setYears(year);

                cp.parseToken(second, bSeconds, false);
                ceb.setBSeconds(bSeconds);
                ceb.setSeconds(second);
                ceb.setBusinessDays(businessDays);
                
			    list.add(ceb);
			}
			rs.close();
		    } else {
			throw new DataNotFoundException("No CrontabEntries available");
		    }
		} finally {
		    try { st.close(); } catch (Exception e) {}
		    try { conn.close(); } catch (Exception e2) {}
		}
                CrontabEntryBean[] result = new CrontabEntryBean[list.size()];
                for (int i = 0; i < list.size(); i++) {
                        result[i] = (CrontabEntryBean)list.get(i);
                }
        return result;
	}
    
    	/**
	 *  This method removes the given Crontab Entries 
	 *  @param CrontabEntryBean bean this method only lets store an