/*
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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.flex.compiler.internal.fxg.sax;
import java.util.Collection;
import java.util.Map;
import java.util.Set;
import java.util.Stack;
import org.xml.sax.Attributes;
import org.xml.sax.Locator;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.DefaultHandler;
import org.apache.flex.compiler.fxg.FXGConstants;
import org.apache.flex.compiler.fxg.dom.IFXGNode;
import org.apache.flex.compiler.internal.fxg.dom.CDATANode;
import org.apache.flex.compiler.internal.fxg.dom.GraphicNode;
import org.apache.flex.compiler.internal.fxg.dom.DefinitionNode;
import org.apache.flex.compiler.internal.fxg.dom.DelegateNode;
import org.apache.flex.compiler.internal.fxg.dom.IPreserveWhiteSpaceNode;
import org.apache.flex.compiler.problems.FXGInvalidRootNodeProblem;
import org.apache.flex.compiler.problems.FXGInvalidVersionProblem;
import org.apache.flex.compiler.problems.FXGMissingAttributeProblem;
import org.apache.flex.compiler.problems.FXGMultipleElementProblem;
import org.apache.flex.compiler.problems.FXGPrivateElementNotChildOfGraphicProblem;
import org.apache.flex.compiler.problems.FXGPrivateElementNotLastProblem;
import org.apache.flex.compiler.problems.FXGScanningProblem;
import org.apache.flex.compiler.problems.FXGUnknownElementInVersionProblem;
import org.apache.flex.compiler.problems.FXGVersionHandlerNotRegisteredProblem;
import org.apache.flex.compiler.problems.ICompilerProblem;
import static org.apache.flex.compiler.fxg.FXGConstants.*;
/**
* This SAX2 based scanner converts an FXG document (an XML based description of
* a graphical asset) to a simple object graph to serve as an intermediate
* representation. The document must be in the FXG 1.0 namespace and the root
* element must be a <Graphic> tag.
*/
public class FXGSAXScanner extends DefaultHandler
{
private static boolean REJECT_MAJOR_VERSION_MISMATCH = false;
// A special case needed to short circuit GroupNode creation inside a
// Definition as such Groups are not the same as those in the graphics
// tree.
private static final String FXG_GROUP_DEFINITION_ELEMENT = "[GroupDefinition]";
private GraphicNode root;
private Stack<IFXGNode> stack;
private int skippedElementCount;
private boolean seenPrivateElement = false;
private boolean inMaskAfterPrivateElement = false;
private Locator locator;
private int startLine = 0;
private int startColumn = 0;
private String documentPath = null;
private String unknownElement = null;
private Collection<ICompilerProblem> problems;
// FXG version handler to handle different fxg versions
// depending on input file version at runtime.
private IFXGVersionHandler versionHandler = null;
/**
* Construct a new FXGSAXScanner
*/
public FXGSAXScanner(Collection<ICompilerProblem> problems)
{
super();
this.problems = problems;
versionHandler = FXGVersionHandlerRegistry.getDefaultHandler();
if (versionHandler == null)
problems.add(new FXGVersionHandlerNotRegisteredProblem(FXGVersionHandlerRegistry.defaultVersion.asDouble()));
}
/**
* Provides access to the root IFXGNode of the FXG document AFTER parsing.
*
* @return the root IFXGNode of the DOM.
*/
public IFXGNode getRootNode()
{
return root;
}
//--------------------------------------------------------------------------
//
// SAX DefaultHandler Implementation
//
//--------------------------------------------------------------------------
@Override
public void setDocumentLocator(Locator locator)
{
this.locator = locator;
}
/**
* Get document path used for logging.
*/
public String getDocumentPath()
{
return documentPath;
}
/**
* Set document path used for logging.
*/
public void setDocumentPath(String documentPath)
{
this.documentPath = documentPath;
}
@Override
public void startDocument() throws SAXException
{
stack = new Stack<IFXGNode>();
}
@Override
public void startElement(String uri, String localName, String name,
Attributes attributes) throws SAXException
{
// First check if we're currently skipping elements
if (isSkippedElement(uri, localName, true))
skippedElementCount++;
if (inSkippedElement())
return;
// Check if we're currently skipping unknown elements
if (unknownElement != null)
return;
// Record starting position
startLine = locator.getLineNumber();
startColumn = locator.getColumnNumber();
// Check the current parent
IFXGNode parent = null;
if (stack.size() > 0)
{
parent = stack.peek();
if(parent == null)
{
//If the parent is invalid, then there is no need to look into the children
return;
}
}
// Switch to special GroupDefinitionNode for Definition child
if (isFXGNamespace(uri))
{
if (parent instanceof DefinitionNode && FXG_GROUP_ELEMENT.equals(localName))
localName = FXG_GROUP_DEFINITION_ELEMENT;
}
// Create a node for this element
IFXGNode node = createNode(uri, localName);
try
{
if (node == null)
{
if (root != null)
{
if (root.isVersionGreaterThanCompiler())
{
// Warning: Minor version of this FXG file is greater than minor
// version supported by this compiler. Log a warning for an
// unknown element.
//TODO FXGLOG
//FXGLog.getLogger().log(IFXGLogger.WARN, "UnknownElement", null, documentName, startLine, startColumn);
unknownElement = localName;
}
else
{
problems.add(new FXGUnknownElementInVersionProblem(documentPath, startLine, startColumn, localName, root.getFileVersion().asDouble()));
}
}
else
{
problems.add(new FXGInvalidRootNodeProblem(documentPath, startLine, startColumn));
}
return;
}
// Provide access to the root document node used for querying version
// for non-root elements
if (root != null)
{
node.setDocumentNode(root);
}
// Set node name if it is a delegate node. This allows proper error
// message to be reported.
if (node instanceof DelegateNode)
{
DelegateNode propertyNode = (DelegateNode)node;
propertyNode.setName(localName);
}
// Set attributes on the current node
for (int i = 0; i < attributes.getLength(); i++)
{
String attributeURI = attributes.getURI(i);
if (attributeURI == null || attributeURI == "" || isFXGNamespace(attributeURI))
{
String attributeName = attributes.getLocalName(i);
String attributeValue = attributes.getValue(i);
node.setAttribute(attributeName, attributeValue, problems);
}
}
// Associate child with parent node (and handle any special
// relationships)
if (parent != null)
{
if (node instanceof DelegateNode)
{
DelegateNode propertyNode = (DelegateNode)node;
propertyNode.setDelegate(parent, problems);
}
else
{
parent.addChild(node, problems);
}
}
else if (node instanceof GraphicNode)
{
root = (GraphicNode)node;
// Provide access to the root document node
node.setDocumentNode(root);
if (root.getVersion() == null)
{
for(ICompilerProblem problem : problems)
{
if(problem instanceof FXGInvalidVersionProblem)
{
// There was a version attribute but it was invalid.
return;
}
}
//<Graphic> doesn't have the required attribute "version".
problems.add(new FXGMissingAttributeProblem(documentPath, startLine, startColumn, FXG_VERSION_ATTRIBUTE, root.getNodeName()));
return;
}
else
{
if (!isMajorVersionMatch(root))
{
IFXGVersionHandler newVHandler = FXGVersionHandlerRegistry.getVersionHandler(root.getVersion());
if (newVHandler == null)
{
if (REJECT_MAJOR_VERSION_MISMATCH)
{
// Major version of this FXG file is greater than
// major version supported by this compiler. Cannot process
// the file.
problems.add(new FXGInvalidVersionProblem(documentPath, startLine, startColumn, root.getVersion().asString()));
return;
}
else
{
// Warning: Major version of this FXG file is greater than
// major version supported by this compiler.
//TODO FXGLOG
//FXGLog.getLogger().log(IFXGLogger.WARN, "MajorVersionMismatch", null, getDocumentName(), startLine, startColumn);
//use the latest version handler
versionHandler = FXGVersionHandlerRegistry.getLatestVersionHandler();
if (versionHandler == null)
{
problems.add(new FXGVersionHandlerNotRegisteredProblem(root.getVersion().asDouble()));
return;
}
}
}
else
{
versionHandler = newVHandler;
}
}
}
// Provide reference to the handler for querying version of the
// current document processed.
root.setDocumentPath(documentPath);
root.setVersionGreaterThanCompiler(root.getVersion().greaterThan(versionHandler.getVersion()));
root.setReservedNodes(versionHandler.getElementNodes(uri));
}
else if(root == null)
{
// Exception:<Graphic> must be the root node of an FXG document.
problems.add(new FXGInvalidRootNodeProblem(documentPath, startLine, startColumn));
}
}
finally
{
stack.push(node);
}
}
@Override
public void characters(char[] ch, int start, int length)
throws SAXException
{
if (stack != null && stack.size() > 0 && stack.peek() != null &&
!inSkippedElement() && (unknownElement == null))
{
IFXGNode node = stack.peek();
String content = new String(ch, start, length);
if (!(node instanceof IPreserveWhiteSpaceNode))
{
content = content.trim();
}
if (content.length() > 0)
{
CDATANode cdata = new CDATANode();
cdata.content = content;
assignNodeLocation(cdata);
node.addChild(cdata, problems);
}
}
// Reset starting position
startLine = locator.getLineNumber();
startColumn = locator.getColumnNumber();
}
@Override
public void endElement(String uri, String localName, String name)
throws SAXException
{
if (isSkippedElement(uri, localName, false))
{
skippedElementCount--;
}
else if (unknownElement != null)
{
if (unknownElement.equals(localName))
{
unknownElement = null;
}
}
else if (!inSkippedElement() && stack.peek() != null)
{
stack.pop();
}
// Reset starting position
startLine = locator.getLineNumber();
startColumn = locator.getColumnNumber();
}
//--------------------------------------------------------------------------
//
// Other Methods
//
//--------------------------------------------------------------------------
/**
* @return the last processed line number
*/
public int getStartLine()
{
return startLine;
}
/**
* @return the last processed column number
*/
public int getStartColumn()
{
return startColumn;
}
/**
* @param uri - the namespace URI to check
* @return whether the given namespace URI is considered an FXG namespace.
*/
protected boolean isFXGNamespace(String uri)
{
return FXG_NAMESPACE.equals(uri);
}
/**
* Determines whether an element should be skipped.
*
* @param uri - the namespace URI of the element
* @param localName - the name of the element
* @return true if the element has been marked as skipped, otherwise false.
*/
protected boolean isSkippedElement(String uri, String localName, boolean startElement)
{
Set<String> skippedElements = versionHandler.getSkippedElements(uri);
if (skippedElements != null)
{
if (skippedElements.contains(FXGConstants.FXG_PRIVATE_ELEMENT))
{
validatePrivateElement(localName, startElement);
}
if (skippedElements.contains(localName))
{
return true;
}
}
return false;
}
/**
* Attempts to construct an instance of IFXGNode for the given element.
*
* @param uri - the namespace URI of the element
* @param localName - the name of the element
* @return IFXGNode instance if
*/
protected IFXGNode createNode(String uri, String localName)
{
IFXGNode node = null;
try
{
Map<String, Class<? extends IFXGNode>> elementNodes = getElementNodes(uri);
if (elementNodes != null)
{
Class<? extends IFXGNode> nodeClass = elementNodes.get(localName);
if (nodeClass != null)
{
node = (IFXGNode)nodeClass.newInstance();
}
else if (root != null)
{
node = root.getDefinitionInstance(localName);
}
}
}
catch (Exception e)
{
problems.add(new FXGScanningProblem(documentPath, startLine, startColumn, e.getLocalizedMessage()));
}
if (node != null)
{
assignNodeLocation(node);
}
return node;
}
/**
* @return if currently in a skipped element.
*/
private boolean inSkippedElement()
{
return skippedElementCount > 0;
}
/**
* Record the start and end line and column information for this node.
* @param node - the current node
*/
private void assignNodeLocation(IFXGNode node)
{
if (node != null)
{
node.setStartLine(startLine);
node.setStartColumn(startColumn);
node.setEndLine(locator.getLineNumber());
node.setEndColumn(locator.getColumnNumber());
}
}
/**
* @param uri - the namespace URI of the registered FXG elements.
* @return a Map of the IFXGNode Classes registered for elements in the
* given namespace URI.
*/
private Map<String, Class<? extends IFXGNode>> getElementNodes(String uri)
{
return versionHandler.getElementNodes(uri);
}
/**
* validates restrictions on PRIVATE element
* @param localName
*/
private void validatePrivateElement(String localName, boolean startElement)
{
if (!startElement)
{
if (inMaskAfterPrivateElement && localName.equals(FXGConstants.FXG_MASK_ELEMENT))
inMaskAfterPrivateElement = false;
return;
}
if (localName.equals(FXGConstants.FXG_PRIVATE_ELEMENT))
{
if (seenPrivateElement)
{
problems.add(new FXGMultipleElementProblem(documentPath, startLine, startColumn, localName));
}
else
{
if ((!inSkippedElement()) && stack.size() == 1)
seenPrivateElement = true;
else
problems.add(new FXGPrivateElementNotChildOfGraphicProblem(documentPath, startLine, startColumn));
}
}
else
{
if (seenPrivateElement && (!inSkippedElement()))
{
if ((!inMaskAfterPrivateElement) && (localName.equals(FXGConstants.FXG_MASK_ELEMENT)))
{
inMaskAfterPrivateElement = true;
}
else
{
if (!inMaskAfterPrivateElement)
problems.add(new FXGPrivateElementNotLastProblem(documentPath, startLine, startColumn));
}
}
}
}
/**
* @return - true if major version of the FXG file matches the compiler's
* major version. false otherwise.
*/
private boolean isMajorVersionMatch(GraphicNode root)
{
long majorVersion = root.getVersion().getMajorVersion();
long compilerMajorVersion = versionHandler.getVersion().getMajorVersion();
if (majorVersion == compilerMajorVersion)
return true;
else
return false;
}
}