001    //$HeadURL: svn+ssh://rbezema@svn.wald.intevation.org/deegree/base/tags/2.1/src/org/deegree/enterprise/control/RequestDispatcher.java $
002    /*----------------    FILE HEADER  ------------------------------------------
003    
004     This file is part of deegree.
005     Copyright (C) 2001-2006 by:
006     EXSE, Department of Geography, University of Bonn
007     http://www.giub.uni-bonn.de/deegree/
008     lat/lon GmbH
009     http://www.lat-lon.de
010    
011     This library is free software; you can redistribute it and/or
012     modify it under the terms of the GNU Lesser General Public
013     License as published by the Free Software Foundation; either
014     version 2.1 of the License, or (at your option) any later version.
015    
016     This library is distributed in the hope that it will be useful,
017     but WITHOUT ANY WARRANTY; without even the implied warranty of
018     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
019     Lesser General Public License for more details.
020    
021     You should have received a copy of the GNU Lesser General Public
022     License along with this library; if not, write to the Free Software
023     Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
024    
025     Contact:
026    
027     Andreas Poth
028     lat/lon GmbH
029     Aennchenstr. 19
030     53115 Bonn
031     Germany
032     E-Mail: poth@lat-lon.de
033    
034     Prof. Dr. Klaus Greve
035     Department of Geography
036     University of Bonn
037     Meckenheimer Allee 166
038     53115 Bonn
039     Germany
040     E-Mail: greve@giub.uni-bonn.de
041    
042     
043     ---------------------------------------------------------------------------*/
044    
045    package org.deegree.enterprise.control;
046    
047    import java.io.File;
048    import java.io.IOException;
049    
050    import javax.servlet.ServletConfig;
051    import javax.servlet.ServletException;
052    import javax.servlet.http.HttpServlet;
053    import javax.servlet.http.HttpServletRequest;
054    import javax.servlet.http.HttpServletResponse;
055    
056    import org.deegree.enterprise.servlet.ServletRequestWrapper;
057    
058    /**
059     * This is a <code>RequestDispatcher</code> which creates a event out of a GET
060     * or POST requests.
061     * <P>
062     * 
063     * @author <a href="mailto:poth@lat-lon.de">Andreas Poth </a>
064     * 
065     * @version $Revision: 7335 $ $Date: 2007-05-29 11:43:53 +0200 (Di, 29 Mai 2007) $
066     */
067    public class RequestDispatcher extends HttpServlet {
068    
069        private static final long serialVersionUID = 1L;
070    
071        private static String CONFIGURATION = "Handler.configFile";
072    
073        protected transient ApplicationHandler appHandler = null;
074    
075        /**
076         * This method initializes the servlet.
077         * 
078         * @param cfg
079         *            the servlet configuration
080         * 
081         * @throws ServletException
082         *             an exception
083         */
084        @Override
085        public void init( ServletConfig cfg )
086                                throws ServletException {
087            super.init( cfg );
088    
089            try {
090                String url = null;
091    
092                String s = getInitParameter( CONFIGURATION );
093                if ( new File( s ).isAbsolute() ) {
094                    url = s;
095                } else {
096                    url = getServletContext().getRealPath( s );
097                }
098    
099                this.appHandler = new ApplicationHandler( url );
100            } catch ( Exception e ) {
101                e.printStackTrace();
102            }
103        }
104    
105        /**
106         * 
107         * 
108         * @param request
109         * @param response
110         * 
111         * @throws ServletException
112         * @throws IOException
113         */
114        @Override
115        protected void service( HttpServletRequest request, HttpServletResponse response )
116                                throws ServletException, IOException {
117    //        Map<String, String[]> requestParameters= request.getParameterMap();
118    //        FormEvent event = null;
119    //        if( requestParameters.size() > 0 ){
120    //            Map<String, String> params = new HashMap<String, String>();
121    //            Set<String> keys = requestParameters.keySet();
122    //            for( String key : keys){
123    //                String[] values = requestParameters.get( key );
124    //                //maybe put in more keys with _iterator appended?
125    //                if( values.length >= 1 ){
126    //                    params.put( key, values[0] );
127    //                }
128    //            }
129    //            event = new WebEvent( params );
130    //        } else {
131    //            event = new WebEvent( request.getInputStream() );
132    //         }
133            
134            // create event out of request
135           FormEvent event = createEvent( request );
136    
137            // deliver event to application handler
138            deliverEvent( event );
139    
140            // get next page from request attribute
141            String nextPage = (String) request.getAttribute( "next" );
142    
143            // show error page if next page is null or an error occured
144            nextPage = "/" + ( ( nextPage == null ) ? "error.jsp" : nextPage );
145    
146            if ( request.getAttribute( "javax.servlet.jsp.jspException" ) != null ) {
147                nextPage = "/error.jsp";
148            }
149    
150            // call request dispatcher
151            getServletConfig().getServletContext().getRequestDispatcher( nextPage ).forward( request,
152                                                                                             response );
153            event = null;
154        }
155    
156        /**
157         * 
158         * 
159         * @param original request from the service
160         * 
161         * @return a new WebEvent which wraps the request into a {@link ServletRequestWrapper}.
162         */
163        protected FormEvent createEvent( HttpServletRequest request ) {
164            return new WebEvent( new ServletRequestWrapper( request ) );
165        }
166    
167        /**
168         * 
169         * 
170         * @param event
171         */
172        protected void deliverEvent( FormEvent event ) {
173            if ( appHandler == null ) {
174                try {
175                    String url = null;
176    
177                    String s = getInitParameter( CONFIGURATION );
178                    if ( new File( s ).isAbsolute() ) {
179                        url = s;
180                    } else {
181                        url = getServletContext().getRealPath( s );
182                    }
183    
184                    this.appHandler = new ApplicationHandler( url );
185                } catch ( Exception e ) {
186                    e.printStackTrace();
187                }         
188            }
189            this.appHandler.actionPerformed( event );
190        }
191    }