crontabservletxml.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.web;  

import java.io.File;
import java.io.FileInputStream;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.PrintStream;
import java.io.Reader;
import java.io.StringReader;
import java.util.Vector;
import javax.servlet.ServletContext;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.xml.transform.Result;
import javax.xml.transform.Source;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.stream.StreamResult;
import javax.xml.transform.stream.StreamSource;
import org.jcrontab.data.CrontabEntryBean;
import org.jcrontab.data.CrontabEntryDAO;
import org.jcrontab.data.CrontabParser;
import org.jcrontab.data.DataNotFoundException;
import org.jcrontab.log.Log;

/**
 * This Servlet writes in xml format all the CrontabEntryBean availables.
 * This represents the contoller and the actions in a MVC pattern
 * Usually this servlet is used tiwh a xsl file to generate the final HTML 
 * 
 * @author $Author: iolalla $
 * @version $Revision: 1.28 $
 */
public class CrontabServletXML extends HttpServlet {
    
    /** This variable is the name of the xsl file
     */    
        public static final String xsl = "view.xsl";
		
        /** Refer to Servlet Javadoc
         * @param request This is the servlet request. 
         * refer to the Servlet JavaDoc
         * @param response This is the servlet response 
         * refer to the Servlet JavaDoc
         */        
	public void doPost(HttpServletRequest request,
		HttpServletResponse response) {

		int event = Integer.parseInt( request.getParameter("event"));
		switch(event) {
			case 0 : {
					store(request, response);
					break;
				 }
			case 1 : {
					remove(request, response);
					break;
				 }
		}
	}

        /** Refer to Servlet Javadoc
         * @param request This is the servlet request. 
         * refer to the Servlet JavaDoc
         * @param response This is the servlet response 
         * refer to the Servlet JavaDoc
         */        
	public void doGet (HttpServletRequest request,
    	       HttpServletResponse response) {
		show(request, response);
	}

        /** This method processes the POST information,
         * and saves the info comming from the web
         * @param request This is the servlet request. 
         * refer to the Servlet JavaDoc
         * @param response This is the servlet response 
         * refer to the Servlet JavaDoc
         */        
	public void remove(HttpServletRequest request,
		HttpServletResponse response) {
                Vector errors = new Vector();
		if (request.getParameterValues("remove") == null) {
			errors.add("Must select smth to delete");
			request.setAttribute("error", errors);
			show(request, response);
		} else {
			String[] idToDelete = request.getParameterValues("remove");
			CrontabEntryBean result[] = new CrontabEntryBean[idToDelete.length];
			for (int i = 0; i < idToDelete.length ; i++) {
				CrontabEntryBean resulti = new CrontabEntryBean();
				resulti.setId(Integer.parseInt(idToDelete[i]));
			try {
				result[i] =  CrontabEntryDAO.getInstance().find(resulti); 
			} catch (Exception e) {
				Log.error(e.toString(), e);
			}
			}
			try {
			CrontabEntryDAO.getInstance().remove(result);
			} catch (Exception e){
				errors.add(e.toString());
				request.setAttribute("error", errors);
				Log.error(e.toString(), e);
			}
			show(request, response);   
		}
	}
        /** This method processes the POST information,
         * and saves the info comming from the web-client
         * @param request This is the servlet request. 
         * refer to the Servlet JavaDoc
         * @param response This is the servlet response 
         * refer to the Servlet JavaDoc
         */        
	public void store(HttpServletRequest request,
		HttpServletResponse response) {
                Vector errors = new Vector();
                String Classname = request.getParameter("Classname").trim();
                if (Classname.length() > 0) {
                String Minutes = request.getParameter("Minutes").trim();
                String Hours = request.getParameter("Hours").trim();
                String Daysofmonth = request.getParameter("Daysofmonth").trim();
                String Month = request.getParameter("Month").trim();
                String Daysofweek = request.getParameter("Daysofweek").trim();
                String Extrainfo = request.getParameter("Extrainfo").trim();              
                StringBuffer sb = new StringBuffer();
                sb.append(Minutes);
                sb.append(" ");
                sb.append(Hours);
                sb.append(" ");
                sb.append(Daysofmonth);
                sb.append(" ");
                sb.append(Month);
                sb.append(" ");
                sb.append(Daysofweek);
                sb.append(" ");
                sb.append(Classname);
                sb.append(" ");
                sb.append(Extrainfo);
                try {
					CrontabParser cbp = new CrontabParser();
					CrontabEntryBean cb = cbp.marshall(sb.toString());
					CrontabEntryDAO.getInstance().store(cb);
					show(request, response);
                } catch(Exception e) {
					errors.add(e.toString());
					Log.error(e.toString(), e);
                }
					request.setAttribute("error", errors);
					show(request, response);
                } else {
				errors.add("Must write some class name");
				request.setAttribute("error", errors);
                show(request, response);
                }
        }
        /** 
		 * This method transforms the xml/xsl and prints
         * the whole thing in order to get hte HTML page.
         * Should be called the last.
         * @param request This is the servlet request. 
         * refer to the Servlet JavaDoc
         * @param response This is the servlet response 
         * refer to the Servlet JavaDoc
         */        
        public void show(HttpServletRequest request,
		HttpServletResponse response) {

       		try {
			PrintStream out = new PrintStream(response.getOutputStream());
			CrontabEntryBean[] listOfBeans = null;
			try {
				listOfBeans= CrontabEntryDAO
					.getInstance().findAll();
			} catch (Exception e) {
				if (e instanceof DataNotFoundException) {
				listOfBeans = 
					new CrontabEntryBean[1];
					CrontabParser cbp = new CrontabParser();
					listOfBeans[0] = cbp.marshall(
					"* * * * * org.jcrontab.tests.Example put your own");
				} else {
					Log.error(e.toString(), e);
				}
			}
			StringBuffer sb = new StringBuffer();
			sb.append(printHeader());
			sb.append(processErrors(request));
			sb.append("<crontabentries>");
               for (int i = 0; i < listOfBeans.length; i++) {
				   sb.append(listOfBeans[i].toXML());
		       }
		    sb.append("</crontabentries>");
		    sb.append(printFooter());
                                                
            TransformerFactory tFactory = TransformerFactory.newInstance();
// To test xml can uncomment this line :-)                     
// System.out.println("\n\n\n" + sb.toString() + "\n\n\n" );
			
			
                        Source xmlsource = new StreamSource(
                            new StringReader((String)sb.toString()));
                            /*
                             *The following lines allow to acces to the correct 
                             *xsl file it's quite tricky and surelly should be 
                             *other ways to do in the easy way 
                             *
                             */
			
                        // This line tells the transformer where can find the xsl
                        // file ... jcrontab/...
						File xslFile = new File(getServletContext().getRealPath("/") + xsl); 
                        // This one loads the input stream
                        FileInputStream fileInputStream = 
                                new FileInputStream(xslFile);
                        // This one instiates the Reader neded to transform
						InputStreamReader xslReader = 
                                new InputStreamReader(fileInputStream);
                        
						Source xslSource = new StreamSource(xslReader);

                        Transformer transformer = 
                                tFactory.newTransformer(xslSource);

                        transformer.transform(xmlsource, new StreamResult(out));
			out.close();
  		} catch (Exception ex) {
	    		ex.printStackTrace ();
    		}
		}

                
                
        /** This Method writes the begining of the xml
         * @return String the begining of the xml file
         */      
	private static String printHeader() {
		StringBuffer sb = new StringBuffer(); 
		sb.append("<?xml version=\"1.0\" encoding=\"ISO-8859-1\"?>\n");
	        sb.append("<?xml-stylesheet type=\"text/xsl\" href=\"view.xsl\" ?> \n");
	        sb.append("<page xml:base=\"\"> \n");   
		return sb.toString();
	}

        /** This Method writes the end of the xml
         * @return String the end of the xml file
         */        
	public static String printFooter() {
		return "</page>";
	}
        /** This Method writes the Errors to the xml
         * @return String the the errors to the xml 
         */      
	
	public static String processErrors(HttpServletRequest request ) {
		// setAttribute(error, errorList);
	if (request.getAttribute("error") != null) {
		Vector errorV = (Vector)request.getAttribute("error");
		String errorList[] = new String[errorV.size()];
		for (int i = 0; i < errorV.size(); i++) {
			errorList[i] = (String)errorV.get(i);
		}
		StringBuffer sbi = new StringBuffer();
		for (int i = 0; i < errorList.length; i++) {
			sbi.append("<error><text>");
			sbi.append(errorList[i]);
			sbi.append("</text></error>\n");
		}
		return sbi.toString();
	} else {
		return " ";
	}
	}
}