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Diffstat (limited to 'plugins/org.eclipse.wst.common.emf/wtpemf/org/eclipse/wst/common/internal/emf/resource/EMF2SAXWriter.java')
| -rw-r--r-- | plugins/org.eclipse.wst.common.emf/wtpemf/org/eclipse/wst/common/internal/emf/resource/EMF2SAXWriter.java | 387 |
1 files changed, 0 insertions, 387 deletions
diff --git a/plugins/org.eclipse.wst.common.emf/wtpemf/org/eclipse/wst/common/internal/emf/resource/EMF2SAXWriter.java b/plugins/org.eclipse.wst.common.emf/wtpemf/org/eclipse/wst/common/internal/emf/resource/EMF2SAXWriter.java deleted file mode 100644 index c5d08070e..000000000 --- a/plugins/org.eclipse.wst.common.emf/wtpemf/org/eclipse/wst/common/internal/emf/resource/EMF2SAXWriter.java +++ /dev/null @@ -1,387 +0,0 @@ -/******************************************************************************* - * Copyright (c) 2003, 2004 IBM Corporation and others. - * All rights reserved. This program and the accompanying materials - * are made available under the terms of the Eclipse Public License v1.0 - * which accompanies this distribution, and is available at - * http://www.eclipse.org/legal/epl-v10.html - * - * Contributors: - * IBM Corporation - initial API and implementation - *******************************************************************************/ -package org.eclipse.wst.common.internal.emf.resource; - - -import java.util.List; -import java.util.Stack; - -import org.eclipse.emf.common.util.EList; -import org.eclipse.emf.ecore.EObject; -import org.xml.sax.Attributes; -import org.xml.sax.ContentHandler; -import org.xml.sax.SAXException; -import org.xml.sax.helpers.AttributesImpl; - -/** - * The EMF2SAXWriter handles the serialization of EMF Resources using SAX events. SAX events are - * triggered to the content handler as the tree is being parsed. These events can then be written - * into any stream wrapped by the ContentHandler. - * - * @author mdelder - */ -public class EMF2SAXWriter { - - public static final String NAMESPACE = "";//"http://java.sun.com/xml/ns/j2ee"; //$NON-NLS-1$ - - /* Used in those cases where no Attributes are necessary */ - private static final Attributes EMPTY_ATTRIBUTES = new AttributesImpl(); - - /** - * Serialize an EMF resource into an XML Stream using the given ContentHandler. Note that this - * method can also be used to copy a given EMF Resource if the EMF2SAXDocumentHandler is used as - * the given ContentHandler. - * - * @param resource - * @param handler - */ - public void serialize(TranslatorResource resource, ContentHandler handler) throws SAXException { - - Translator rootTranslator = resource.getRootTranslator(); - EList contents = resource.getContents(); - - if (contents.size() != 1) { - throw new IllegalStateException("The contents of a resource may only contain one EMF Model Object."); //$NON-NLS-1$ - } - handler.startDocument(); - EObject element = (EObject) contents.get(0); - serialize(handler, element, rootTranslator, new WriterHints(resource)); - handler.endDocument(); - - } - - private void serialize(ContentHandler handler, EObject target, Translator translator, WriterHints hints) throws SAXException { - - List mofChildren = null; - Object rawValue = null; - EObject newTarget = null; - Translator currentChildTranslator = null; - Translator nextTranslator = null; - char[] characterData = null; - String convertedValue = null; - Attributes attributes = null; - String childDomName = null; - final int version = hints.getVersion(); - - /* - * Processing hints are used to remember where are in the iteration of the translator's - * children. see the TranslatorFilter for more information on how this array is used. - */ - int[] processingHints = TranslatorFilter.createProcessingHints(); - - String targetDomName = translator.getDOMName(target); - - attributes = getAttributes(translator, target, hints); - - handler.startElement(NAMESPACE, targetDomName, targetDomName, attributes); - - currentChildTranslator = TranslatorFilter.getNextObjectTranslator(translator, processingHints[TranslatorFilter.NEXT_START_HINT_INDX], processingHints, target, version); - while (currentChildTranslator != null) { - /* For each Child Translator of the Translator parameter passed into the method */ - - /* Does the Translator have any MOF Children? */ - mofChildren = currentChildTranslator.getMOFChildren(target); - openDomPathIfNecessary(handler, hints, currentChildTranslator, target, mofChildren); - - if (currentChildTranslator.isManagedByParent()) { - /* - * Translators which are managed by their parents require less processing -- just - * convert their value to a string and write it out as the content of an XML element - */ - childDomName = currentChildTranslator.getDOMName(target); - if (!currentChildTranslator.isEmptyTag()) { - /* The Translator is not an Empty tag. Its text content is significant */ - - if (mofChildren.size() > 0) { - for (int j = 0; j < mofChildren.size(); j++) { - - /* Text only translators will not have open and close XML elements */ - if (!currentChildTranslator.isDOMTextValue()) - handler.startElement(NAMESPACE, childDomName, childDomName, EMPTY_ATTRIBUTES); - - rawValue = mofChildren.get(j); - /* convertValueToString should always return a non-null String */ - convertedValue = currentChildTranslator.convertValueToString(rawValue, target); - characterData = XMLEncoderDecoder.escape(convertedValue).toCharArray(); - handler.characters(characterData, 0, characterData.length); - - if (!currentChildTranslator.isDOMTextValue()) - handler.endElement(NAMESPACE, childDomName, childDomName); - } - } - } else { - /* - * The Translator is an Empty Element (its mere presence has significance) (e.g. - * <cascade-delete/> - */ - - if (currentChildTranslator.isBooleanFeature()) { - /* Boolean features may or may not be rendered */ - rawValue = mofChildren.get(0); - if (rawValue != null && ((Boolean) rawValue).booleanValue()) { - handler.startElement(NAMESPACE, childDomName, childDomName, EMPTY_ATTRIBUTES); - handler.endElement(NAMESPACE, childDomName, childDomName); - } - - } else { - /* Always render any other Empty elements */ - handler.startElement(NAMESPACE, childDomName, childDomName, EMPTY_ATTRIBUTES); - handler.endElement(NAMESPACE, childDomName, childDomName); - } - } - } else { - - /* The Translator is a more complex feature, handle its processing recursively */ - for (int j = 0; j < mofChildren.size(); j++) { - newTarget = (EObject) mofChildren.get(j); - serialize(handler, newTarget, currentChildTranslator, hints); - } - } - - /* Fetch the next peer translator */ - nextTranslator = TranslatorFilter.getNextObjectTranslator(translator, processingHints[TranslatorFilter.NEXT_START_HINT_INDX], processingHints, target, version); - - closeDomPathIfNecessary(handler, hints, currentChildTranslator, nextTranslator, target, mofChildren); - - /* - * We needed to invoke closeDomPathIfNecessary() with the peer, now we move on to - * process that peer - */ - currentChildTranslator = nextTranslator; - - } - handler.endElement(NAMESPACE, targetDomName, targetDomName); - } - - /** - * Determines whether or not a DOM Path should be rendered. This method is particularly useful - * for determining whether Empty XML elements are relevant and should be written to the XML - * stream. - * - * @param target - * The EMF Target of the Translation - * @param currentChildTranslator - * The current Translator - * @param mofChildren - * The mofChildren that were found for the Translator on the Target - * @return - */ - private boolean shouldRenderDomPath(EObject target, Translator currentChildTranslator, List mofChildren) { - return !currentChildTranslator.isEmptyContentSignificant() || (currentChildTranslator.shouldRenderEmptyDOMPath(target) || mofChildren.size() > 0); - } - - /** - * openDomPathIfNecessary will write the current DOM Path to the serialization stream if it has - * not been written by a previous peer translator. The processing results in the collapse of - * Peer Translators with matching DOM Paths into a single XML parent element. - * - * @param handler - * The ContentHandler which is writing the XML result - * @param hints - * A Global container for information specific to a single XML document - * @param currentChildTranslator - * The active Translator being processed - * @param target - * The EMF Target of the Translation - * @throws SAXException - */ - private void openDomPathIfNecessary(ContentHandler handler, WriterHints hints, Translator currentChildTranslator, EObject target, List mofChildren) throws SAXException { - - /* If the translator does not have a DOM Path, then we do nothing */ - if (currentChildTranslator.hasDOMPath() && shouldRenderDomPath(target, currentChildTranslator, mofChildren)) { - - String childDomPath = currentChildTranslator.getDOMPath(); - - /* - * IsDomPathActive() will verify whether this DOM Path has already been written to the - * XML stream - */ - if (!hints.isDomPathActive(childDomPath)) { - - /* - * Write an open element for the DOM Path and "remember" that we have written it - */ - handler.startElement(NAMESPACE, childDomPath, childDomPath, EMPTY_ATTRIBUTES); - hints.pushDomPath(childDomPath); - } - - } - } - - /** - * closeDomPathIfNecessary will determine whether the next peer Translator shares the active DOM - * Path of the current Translator. If the next peer Translator has the same DOM Path, no action - * will be taken (hence condensing the elements into a single XML parent). However, if the DOM - * Path differs (including the Next Peer Translator has no DOM Path) then the current DOM Path - * will be closed (a close XML element is generated. - * - * @param handler - * The ContentHandler which is writing the XML result - * @param hints - * A Global container for information specific to a single XML document - * @param currentChildTranslator - * The last Translator to have completed processing - * @param nextTranslator - * The next peer Translator that will become active - * @param target - * The EMF Target of the Translation - * @throws SAXException - */ - private void closeDomPathIfNecessary(ContentHandler handler, WriterHints hints, Translator currentChildTranslator, Translator nextTranslator, EObject target, List mofChildren) throws SAXException { - - if (currentChildTranslator.hasDOMPath() && shouldRenderDomPath(target, currentChildTranslator, mofChildren)) { - String childDomPath = currentChildTranslator.getDOMPath(); - if (nextTranslator != null) { /* - * There are more peers after this element, we can peek - * ahead - */ - String nextPeerDomPath = nextTranslator.getDOMPath(); - if (nextPeerDomPath == null || !nextPeerDomPath.equals(childDomPath)) { - handler.endElement(NAMESPACE, childDomPath, childDomPath); - hints.popDomPath(); - } - - } else { /* This was the last child element, we must close the dompath */ - handler.endElement(NAMESPACE, childDomPath, childDomPath); - hints.popDomPath(); - } - } - } - - /** - * Aggregate the Attribute translator children from a given translator. This method will request - * the AttributesImpl object from the WriterHints object. The WriterHints maintains this - * reusable collection to limit the requirement for new object creation. - * - * @param translator - * @param target - * @param hints - * @return an initialized set of Attributes for the given Translator and EMF Target - */ - private Attributes getAttributes(Translator translator, EObject target, WriterHints hints) { - - AttributesImpl attributes = hints.getAttributeHolder(); - int version = hints.getVersion(); - Object rawValue = null; - String convertedValue = null; - String childDomName = null; - Translator attributeTranslator = null; - int[] processingHints = TranslatorFilter.createProcessingHints(); - - while ((attributeTranslator = TranslatorFilter.getNextAttributeTranslator(translator, processingHints[TranslatorFilter.NEXT_START_HINT_INDX], processingHints, target, version)) != null) { - - List mofChildren = attributeTranslator.getMOFChildren(target); - if (mofChildren.size() > 0) { - for (int j = 0; j < mofChildren.size(); j++) { - - childDomName = attributeTranslator.getDOMName(target); - rawValue = mofChildren.get(j); - convertedValue = attributeTranslator.convertValueToString(rawValue, target); - convertedValue = XMLEncoderDecoder.escape(convertedValue); - attributes.addAttribute(NAMESPACE, childDomName, childDomName, "String", convertedValue); //$NON-NLS-1$ - } - - } else { - childDomName = attributeTranslator.getDOMName(target); - convertedValue = (String) attributeTranslator.getMOFValue(target); - if (convertedValue != null) - attributes.addAttribute(NAMESPACE, childDomName, childDomName, "String", convertedValue); //$NON-NLS-1$ - } - } - return attributes; - } - - /** - * WriterHints is used to "remember" certain pieces of information while the writer is - * processing. Of particular interest are the version and the state of the DOM Path output. - * Consecutive elements with consistent (identical) DOM Paths are collapsed under a single XML - * element. - * - * The WriterHints provides global state between recursive invocations of serialize(). It should - * be not be used to store local data (e.g. data that is only relevant to a single Translator in - * a given context). - * - * The WriterHints also stores an AttributesImpl object that is re-used to store attributes. The - * getAttributes() method will request the Attributes Holder. - * - * @author mdelder - */ - public final class WriterHints { - private final TranslatorResource resource; - private final Stack domStack = new Stack(); - private final AttributesImpl attributesImpl = new AttributesImpl(); - - public WriterHints(TranslatorResource res) { - this.resource = res; - } - - /** - * Push a new domPath onto the stack - * - * @param domPath - * a DOMPath which has been written to the XML stream - */ - public void pushDomPath(String domPath) { - - if (domPath != null && domPath.length() > 0) - domStack.push(domPath); - } - - /** - * Pop the current domPath from the Array - */ - public void popDomPath() { - - if (!domStack.isEmpty()) - domStack.pop(); - } - - /** - * Determines if the given DOMPath has already been written to the XML stream - * - * @param domPath - * @return true if the given DOMPath has already been written to the XML stream - */ - public boolean isDomPathActive(String domPath) { - boolean result = false; - if (!domStack.isEmpty()) { - - String currentDomPath = (String) domStack.peek(); - if (currentDomPath != null && domPath != null) - result = currentDomPath.equals(domPath); - else if (!(currentDomPath == null ^ domPath == null)) - result = true; - } - - return result; - } - - /** - * @return the version of the EMF Resource - */ - public int getVersion() { - return this.resource.getVersionID(); - } - - /** - * Returns an empty AttributesImpl object to store attributes. Within the context of a given - * WriterHints object (and hence single XML document), the object returned is a singleton. - * The same AttributesImpl object is cleared and reused for each invocation. - * - * @return an empty AttributesImpl object to store attributes - */ - public AttributesImpl getAttributeHolder() { - this.attributesImpl.clear(); - return this.attributesImpl; - } - - } -}
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