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/* * Copyright 2005 The Apache Software Foundation. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.apache.cocoon.generation; import java.io.IOException; import java.util.List; import java.util.Map; import org.apache.avalon.framework.parameters.Parameters; import org.apache.cocoon.ProcessingException; import org.apache.cocoon.environment.ObjectModelHelper; import org.apache.cocoon.environment.SourceResolver; import org.apache.cocoon.util.location.LocatableException; import org.apache.cocoon.util.location.Location; import org.apache.cocoon.util.location.LocationUtils; import org.apache.cocoon.util.location.MultiLocatable; import org.apache.cocoon.xml.AttributesImpl; import org.apache.commons.lang.SystemUtils; import org.apache.commons.lang.exception.ExceptionUtils; import org.xml.sax.Attributes; import org.xml.sax.ContentHandler; import org.xml.sax.SAXException; /** * A generator that dumps an XML representation of the exception raised during a pipeline execution. * <p> * The Cocoon stack trace is produced, reflecting all locations the original exception went through, * along with the root exception stacktrace and the full exception stacktrace. * * @since 2.1.8 * @version $Id: ExceptionGenerator.java 367017 2006-01-08 11:09:40Z antonio $ */ public class ExceptionGenerator extends AbstractGenerator { private Throwable thr; public static final String EXCEPTION_NS = "http://apache.org/cocoon/exception/1.0"; public void setup(SourceResolver resolver, Map objectModel, String src, Parameters par) throws ProcessingException, SAXException, IOException { super.setup(resolver, objectModel, src, par); thr = (Throwable) objectModel.get(ObjectModelHelper.THROWABLE_OBJECT); if (thr == null) { throw new ProcessingException("ExceptionGenerator should be used in <map:handle-errors>"); } } public void generate() throws IOException, SAXException, ProcessingException { this.contentHandler.startDocument(); toSAX(thr, this.contentHandler); this.contentHandler.endDocument(); } public static void toSAX(Throwable thr, ContentHandler handler) throws SAXException { Throwable root = ExceptionUtils.getRootCause(thr); if (root == null) root = thr; AttributesImpl attr = new AttributesImpl(); handler.startPrefixMapping("ex", EXCEPTION_NS); attr.addCDATAAttribute("class", root.getClass().getName()); handler.startElement(EXCEPTION_NS, "exception-report", "ex:exception-report", attr); // Root exception location Location loc = LocationUtils.getLocation(root); if (LocationUtils.isKnown(loc)) { attr.clear(); dumpLocation(loc, attr, handler); } // Root exception message attr.clear(); String message = root instanceof LocatableException ? ((LocatableException) root).getRawMessage() : root.getMessage(); simpleElement("message", attr, message, handler); // Cocoon stacktrace: dump all located exceptions in the exception stack handler.startElement(EXCEPTION_NS, "cocoon-stacktrace", "ex:cocoon-stacktrace", attr); Throwable current = thr; while (current != null) { loc = LocationUtils.getLocation(current); if (LocationUtils.isKnown(loc)) { // One or more locations: dump it handler.startElement(EXCEPTION_NS, "exception", "ex:exception", attr); message = current instanceof LocatableException ? ((LocatableException) current).getRawMessage() : current.getMessage(); simpleElement("message", attr, message, handler); attr.clear(); handler.startElement(EXCEPTION_NS, "locations", "ex:locations", attr); dumpLocation(loc, attr, handler); if (current instanceof MultiLocatable) { List locations = ((MultiLocatable) current).getLocations(); for (int i = 1; i < locations.size(); i++) { // start at 1 because we already dumped the first one attr.clear(); dumpLocation((Location) locations.get(i), attr, handler); } } handler.endElement(EXCEPTION_NS, "locations", "ex:locations"); handler.endElement(EXCEPTION_NS, "exception", "ex:exception"); } // Dump parent location current = ExceptionUtils.getCause(current); } handler.endElement(EXCEPTION_NS, "cocoon-stacktrace", "ex:cocoon-stacktrace"); // Root exception stacktrace attr.clear(); simpleElement("stacktrace", attr, ExceptionUtils.getStackTrace(root), handler); // Full stack trace (if exception is chained) if (thr != root) { String trace = SystemUtils.isJavaVersionAtLeast(140) ? ExceptionUtils.getStackTrace(thr) : ExceptionUtils.getFullStackTrace(thr); simpleElement("full-stacktrace", attr, trace, handler); } handler.endElement(EXCEPTION_NS, "exception-report", "ex:exception-report"); handler.endPrefixMapping("ex"); } private static void dumpLocation(Location loc, AttributesImpl attr, ContentHandler handler) throws SAXException { attr.addCDATAAttribute("uri", loc.getURI()); attr.addCDATAAttribute("line", Integer.toString(loc.getLineNumber())); attr.addCDATAAttribute("column", Integer.toString(loc.getColumnNumber())); simpleElement("location", attr, loc.getDescription(), handler); } private static void simpleElement(String name, Attributes attr, String value, ContentHandler handler) throws SAXException { handler.startElement(EXCEPTION_NS, name, "ex:" + name, attr); if (value != null && value.length() > 0) { handler.characters(value.toCharArray(), 0, value.length()); } handler.endElement(EXCEPTION_NS, name, "ex:" + name); } }