batik-dom/src/main/java/org/apache/batik/dom/StyleSheetProcessingInstruction.java

/*

   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.batik.dom;

import org.apache.batik.dom.util.DOMUtilities;

import org.w3c.dom.DOMException;
import org.w3c.dom.Node;
import org.w3c.dom.stylesheets.LinkStyle;
import org.w3c.dom.stylesheets.StyleSheet;

import java.util.HashMap;

/**
 * This class provides an implementation of the 'xml-stylesheet' processing
 * instructions.
 *
 * @author <a href="mailto:stephane@hillion.org">Stephane Hillion</a>
 * @version $Id$
 */
public class StyleSheetProcessingInstruction
    extends AbstractProcessingInstruction
    implements LinkStyle {

    /**
     * Is this node immutable?
     */
    protected boolean readonly;

    /**
     * The style sheet.
     */
    protected transient StyleSheet sheet;

    /**
     * The stylesheet factory.
     */
    protected StyleSheetFactory factory;

    /**
     * The pseudo attributes.
     */
    protected transient HashMap<String, String> pseudoAttributes;

    /**
     * Creates a new ProcessingInstruction object.
     */
    protected StyleSheetProcessingInstruction() {
    }

    /**
     * Creates a new ProcessingInstruction object.
     */
    public StyleSheetProcessingInstruction(String            data,
                                           AbstractDocument  owner,
                                           StyleSheetFactory f) {
        ownerDocument = owner;
        setData(data);
        factory = f;
    }

    /**
     * Tests whether this node is readonly.
     */
    public boolean isReadonly() {
        return readonly;
    }

    /**
     * Sets this node readonly attribute.
     */
    public void setReadonly(boolean v) {
        readonly = v;
    }

    /**
     * Sets the node name.
     */
    public void setNodeName(String v) {
    }

    /**
     * <b>DOM</b>: Implements {@link
     * org.w3c.dom.ProcessingInstruction#getTarget()}.
     * @return "xml-stylesheet".
     */
    public String getTarget() {
        return "xml-stylesheet";
    }

    /**
     *  The style sheet. 
     */
    public StyleSheet getSheet() {
        if (sheet == null) {
            sheet = factory.createStyleSheet(this, getPseudoAttributes());
        }
        return sheet;
    }

    /**
     * Returns the pseudo attributes in a table.
     */
    public HashMap<String, String> getPseudoAttributes() {
        if (pseudoAttributes == null) {
            pseudoAttributes = new HashMap<String, String>();
            pseudoAttributes.put("alternate", "no");
            pseudoAttributes.put("media",     "all");
            DOMUtilities.parseStyleSheetPIData(data, pseudoAttributes);
        }
        return pseudoAttributes;
    }

    /**
     * <b>DOM</b>: Implements {@link
     * org.w3c.dom.ProcessingInstruction#setData(String)}.
     */
    public void setData(String data) throws DOMException {
        super.setData(data);
        sheet = null;
        pseudoAttributes = null;
    }

    /**
     * Returns a new uninitialized instance of this object's class.
     */
    protected Node newNode() {
        return new StyleSheetProcessingInstruction();
    }
}