001    /*
002     * Copyright (c) 2005 Marko Karppinen & Co. LLC
003     *
004     * Permission is hereby granted, free of charge, to any person obtaining a 
005     * copy of this software and associated documentation files (the "Software"), 
006     * to deal in the Software without restriction, including without limitation 
007     * the rights to use, copy, modify, merge, publish, distribute, sublicense, 
008     * and/or sell copies of the Software, and to permit persons to whom the 
009     * Software is furnished to do so, subject to the following conditions:
010     *
011     * The above copyright notice and this permission notice shall be included in 
012     * all copies or substantial portions of the Software.
013     *
014     * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 
015     * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 
016     * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL 
017     * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 
018     * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING 
019     * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER 
020     * DEALINGS IN THE SOFTWARE.
021     */
022    
023    package fi.karppinen.xml;
024    
025    import gnu.xml.pipeline.EventConsumer;
026    import gnu.xml.pipeline.EventFilter;
027    
028    import java.lang.reflect.InvocationTargetException;
029    import java.lang.reflect.Method;
030    
031    import org.apache.log4j.Logger;
032    import org.xml.sax.SAXException;
033    
034    /**
035     * Invokes a method named in a PI. Eg. <code>&lt;?method <var>doFoo</var>?&gt;</code>
036     * 
037     * @version $Id: MethodInvocator.java,v 1.2 2006/12/01 12:37:00 hsivonen Exp $
038     * @author hsivonen
039     */
040    public class MethodInvocator extends EventFilter {
041        private static final Logger log4j = Logger.getLogger(MethodInvocator.class);
042    
043        private Object obj;
044        
045        private Class<? extends Object> clazz;
046        
047        /**
048         * @param obj the object whose methods to invoke
049         */
050        public MethodInvocator(Object obj) {
051            super();
052            this.obj = obj;
053            this.clazz = obj.getClass();
054            setContentHandler(this);
055        }
056    
057        /**
058         * @param obj the object whose methods to invoke
059         */
060        public MethodInvocator(Object obj, EventConsumer ec) {
061            super(ec);
062            this.obj = obj;
063            this.clazz = obj.getClass();
064            setContentHandler(this);
065        }
066    
067        /**
068         * @see org.xml.sax.ContentHandler#processingInstruction(java.lang.String, java.lang.String)
069         */
070        public void processingInstruction(String target, String data)
071                throws SAXException {
072            if ("method".equals(target)) {
073                String trimmed = data.trim();
074                try {
075                    Method method = clazz.getMethod(trimmed, null);
076                    method.invoke(obj, null);
077                } catch (SecurityException e) {
078                    log4j.error("SecurityException", e);
079                    throw new SAXException(e);
080                } catch (NoSuchMethodException e) {
081                    log4j.error("NoSuchMethodException", e);
082                    throw new SAXException(e);
083                } catch (IllegalArgumentException e) {
084                    log4j.error("IllegalArgumentException", e);
085                    throw new SAXException(e);
086                } catch (IllegalAccessException e) {
087                    log4j.error("IllegalAccessException", e);
088                    throw new SAXException(e);
089                } catch (InvocationTargetException e) {
090                    Throwable t = e.getTargetException();
091                    log4j.error("Throwable", t);
092                    if (t instanceof SAXException) {
093                        throw (SAXException)t;
094                    } else if(t instanceof Exception) {
095                        throw new SAXException((Exception)t);
096                    } else {
097                        throw new SAXException(e);
098                    }
099                }
100            } else {
101                super.processingInstruction(target, data);
102            }
103        }
104    }