org.apache.fop.fo.ElementMapping Maven / Gradle / Ivy
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* 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.
*/
/* $Id: ElementMapping.java 1610839 2014-07-15 20:25:58Z vhennebert $ */
package org.apache.fop.fo;
import java.util.HashMap;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import org.w3c.dom.DOMImplementation;
import org.apache.xmlgraphics.util.QName;
/**
* Abstract base class for Element Mappings (including FO Element Mappings)
* which provide the framework of valid elements and attributes for a given
* namespace.
*/
public abstract class ElementMapping {
/** constant for defining the default value */
public static final String DEFAULT = "";
/** The HashMap table of formatting objects defined by the ElementMapping */
protected HashMap foObjs;
//Please don't change that to java.util.Map as that can break extensions.
/** The namespace for the ElementMapping */
protected String namespaceURI;
/**
* Returns a HashMap of maker objects for this element mapping
*
* @return Table of Maker objects for this ElementMapping
*/
public HashMap getTable() {
if (foObjs == null) {
initialize();
}
return foObjs;
}
/**
* Returns the namespace URI for this element mapping
*
* @return Namespace URI for this element mapping
*/
public String getNamespaceURI() {
return namespaceURI;
}
/**
* Returns the DOMImplementation used by this ElementMapping. The value returned may be null
* for cases where no DOM is used to represent the element tree (XSL-FO, for example). This
* method is used by the intermediate format to instantiate the right kind of DOM document
* for foreign objects. For example, SVG handled through Apache Batik has to use a special
* DOMImplementation.
* @return the DOMImplementation used by this ElementMapping, may be null
*/
public DOMImplementation getDOMImplementation() {
return null; //For namespaces not used in foreign objects
}
/**
* @return the default DOMImplementation when no specialized DOM is necessary.
*/
public static DOMImplementation getDefaultDOMImplementation() {
DocumentBuilderFactory fact = DocumentBuilderFactory.newInstance();
fact.setNamespaceAware(true);
fact.setValidating(false);
try {
return fact.newDocumentBuilder().getDOMImplementation();
} catch (ParserConfigurationException e) {
throw new RuntimeException(
"Cannot return default DOM implementation: " + e.getMessage());
}
}
/** @return the standard namespace prefix for this namespace or null if it is not known. */
public String getStandardPrefix() {
return null;
}
/**
* Indicates whether a particular attribute of the namespace is a property, i.e. the attribute
* value should be converted to a property value.
* @param attributeName the attribute name
* @return true if the attribute should be converted to a property
*/
public boolean isAttributeProperty(QName attributeName) {
return false;
}
/**
* Initializes the set of maker objects associated with this ElementMapping
*/
protected abstract void initialize();
/**
* Base class for all Makers. It is responsible to return the right kind of FONode for a
* particular element.
*/
public static class Maker {
/**
* Creates a new FONode (or rather a specialized subclass of it).
* @param parent the parent FONode
* @return the newly created FONode instance
*/
public FONode make(FONode parent) {
return null;
}
}
}