1 /* 2 * Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26 package com.sun.xml.internal.bind.v2.runtime.unmarshaller; 27 28 import java.util.Collection; 29 import java.util.Collections; 30 31 import javax.xml.bind.Unmarshaller; 32 import javax.xml.bind.ValidationEvent; 33 import javax.xml.bind.helpers.ValidationEventImpl; 34 import javax.xml.namespace.QName; 35 36 import com.sun.xml.internal.bind.v2.runtime.JaxBeanInfo; 37 38 import org.xml.sax.SAXException; 39 40 /** 41 * @author Kohsuke Kawaguchi 42 */ 43 public abstract class Loader { 44 45 // allow derived classes to change it later 46 protected boolean expectText; 47 48 protected Loader(boolean expectText) { 49 this.expectText = expectText; 50 } 51 52 protected Loader() { 53 } 54 55 // 56 // 57 // 58 // Contract 59 // 60 // 61 // 62 /** 63 * Called when the loader is activated, which is when a new start tag is seen 64 * and when the parent designated this loader as the child loader. 65 * 66 * <p> 67 * The callee may change <tt>state.loader</tt> to designate another {@link Loader} 68 * for the processing. It's the responsibility of the callee to forward the startElement 69 * event in such a case. 70 * 71 * @param ea 72 * info about the start tag. never null. 73 */ 74 public void startElement(UnmarshallingContext.State state,TagName ea) throws SAXException { 75 } 76 77 /** 78 * Called when this loaderis an active loaderand we see a new child start tag. 79 * 80 * <p> 81 * The callee is expected to designate another loaderas a loaderthat processes 82 * this element, then it should also register a {@link Receiver}. 83 * The designated loaderwill become an active loader. 84 * 85 * <p> 86 * The default implementation reports an error saying an element is unexpected. 87 */ 88 public void childElement(UnmarshallingContext.State state, TagName ea) throws SAXException { 89 // notify the error, then recover by ignoring the whole element. 90 reportUnexpectedChildElement(ea, true); 91 state.loader = Discarder.INSTANCE; 92 state.receiver = null; 93 } 94 95 @SuppressWarnings({"StringEquality"}) 96 protected final void reportUnexpectedChildElement(TagName ea, boolean canRecover) throws SAXException { 97 if (canRecover) { 98 // this error happens particurly often (when input documents contain a lot of unexpected elements to be ignored), 99 // so don't bother computing all the messages and etc if we know that 100 // there's no event handler to receive the error in the end. See #286 101 UnmarshallingContext context = UnmarshallingContext.getInstance(); 102 if (!context.parent.hasEventHandler() // is somebody listening? 103 || !context.shouldErrorBeReported()) // should we report error? 104 return; 105 } 106 if(ea.uri!=ea.uri.intern() || ea.local!=ea.local.intern()) 107 reportError(Messages.UNINTERNED_STRINGS.format(), canRecover ); 108 else 109 reportError(Messages.UNEXPECTED_ELEMENT.format(ea.uri,ea.local,computeExpectedElements()), canRecover ); 110 } 111 112 /** 113 * Returns a set of tag names expected as possible child elements in this context. 114 */ 115 public Collection<QName> getExpectedChildElements() { 116 return Collections.emptyList(); 117 } 118 119 /** 120 * Returns a set of tag names expected as possible child elements in this context. 121 */ 122 public Collection<QName> getExpectedAttributes() { 123 return Collections.emptyList(); 124 } 125 126 /** 127 * Called when this loaderis an active loaderand we see a chunk of text. 128 * 129 * The runtime makes sure that adjacent characters (even those separated 130 * by comments, PIs, etc) are reported as one event. 131 * IOW, you won't see two text event calls in a row. 132 */ 133 public void text(UnmarshallingContext.State state, CharSequence text) throws SAXException { 134 // make str printable 135 text = text.toString().replace('\r',' ').replace('\n',' ').replace('\t',' ').trim(); 136 reportError(Messages.UNEXPECTED_TEXT.format(text), true ); 137 } 138 139 /** 140 * True if this loader expects the {@link #text(UnmarshallingContext.State, CharSequence)} method 141 * to be called. False otherwise. 142 */ 143 public final boolean expectText() { 144 return expectText; 145 } 146 147 148 /** 149 * Called when this loaderis an active loaderand we see an end tag. 150 */ 151 public void leaveElement(UnmarshallingContext.State state, TagName ea) throws SAXException { 152 } 153 154 155 156 157 158 159 160 161 162 163 // 164 // 165 // 166 // utility methods 167 // 168 // 169 // 170 /** 171 * Computes the names of possible root elements for a better error diagnosis. 172 */ 173 private String computeExpectedElements() { 174 StringBuilder r = new StringBuilder(); 175 176 for( QName n : getExpectedChildElements() ) { 177 if(r.length()!=0) r.append(','); 178 r.append("<{").append(n.getNamespaceURI()).append('}').append(n.getLocalPart()).append('>'); 179 } 180 if(r.length()==0) { 181 return "(none)"; 182 } 183 184 return r.toString(); 185 } 186 187 /** 188 * Fires the beforeUnmarshal event if necessary. 189 * 190 * @param state 191 * state of the newly create child object. 192 */ 193 protected final void fireBeforeUnmarshal(JaxBeanInfo beanInfo, Object child, UnmarshallingContext.State state) throws SAXException { 194 if(beanInfo.lookForLifecycleMethods()) { 195 UnmarshallingContext context = state.getContext(); 196 Unmarshaller.Listener listener = context.parent.getListener(); 197 if(beanInfo.hasBeforeUnmarshalMethod()) { 198 beanInfo.invokeBeforeUnmarshalMethod(context.parent, child, state.prev.target); 199 } 200 if(listener!=null) { 201 listener.beforeUnmarshal(child, state.prev.target); 202 } 203 } 204 } 205 206 /** 207 * Fires the afterUnmarshal event if necessary. 208 * 209 * @param state 210 * state of the parent object 211 */ 212 protected final void fireAfterUnmarshal(JaxBeanInfo beanInfo, Object child, UnmarshallingContext.State state) throws SAXException { 213 // fire the event callback 214 if(beanInfo.lookForLifecycleMethods()) { 215 UnmarshallingContext context = state.getContext(); 216 Unmarshaller.Listener listener = context.parent.getListener(); 217 if(beanInfo.hasAfterUnmarshalMethod()) { 218 beanInfo.invokeAfterUnmarshalMethod(context.parent, child, state.target); 219 } 220 if(listener!=null) 221 listener.afterUnmarshal(child, state.target); 222 } 223 } 224 225 226 /** 227 * Last resort when something goes terribly wrong within the unmarshaller. 228 */ 229 protected static void handleGenericException(Exception e) throws SAXException { 230 handleGenericException(e,false); 231 } 232 233 public static void handleGenericException(Exception e, boolean canRecover) throws SAXException { 234 reportError(e.getMessage(), e, canRecover ); 235 } 236 237 public static void handleGenericError(Error e) throws SAXException { 238 reportError(e.getMessage(), false); 239 } 240 241 protected static void reportError(String msg, boolean canRecover) throws SAXException { 242 reportError(msg, null, canRecover ); 243 } 244 245 public static void reportError(String msg, Exception nested, boolean canRecover) throws SAXException { 246 UnmarshallingContext context = UnmarshallingContext.getInstance(); 247 context.handleEvent( new ValidationEventImpl( 248 canRecover? ValidationEvent.ERROR : ValidationEvent.FATAL_ERROR, 249 msg, 250 context.getLocator().getLocation(), 251 nested ), canRecover ); 252 } 253 254 /** 255 * This method is called by the generated derived class 256 * when a datatype parse method throws an exception. 257 */ 258 protected static void handleParseConversionException(UnmarshallingContext.State state, Exception e) throws SAXException { 259 // wrap it into a ParseConversionEvent and report it 260 state.getContext().handleError(e); 261 } 262 }