fop/src/java/org/apache/fop/fo/flow/Wrapper.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.
 */

/* $Id$ */

package org.apache.fop.fo.flow;

import org.xml.sax.Locator;

import org.apache.fop.apps.FOPException;
import org.apache.fop.fo.FONode;
import org.apache.fop.fo.FObjMixed;
import org.apache.fop.fo.PropertyList;
import org.apache.fop.fo.ValidationException;

/**
 * Class modelling the fo:wrapper object.
 * The wrapper object serves as a property holder for 
 * its child node objects.
 */
public class Wrapper extends FObjMixed {
    // The value of properties relevant for fo:wrapper.
    // End of property values
    
    // used for FO validation
    private boolean blockOrInlineItemFound = false;
    private boolean inlineChildrenAllowed = false;

    /**
     * @param parent FONode that is the parent of this object
     */
    public Wrapper(FONode parent) {
        super(parent);
        /* Check if the fo:wrapper is a child of a FO that allows mixed content
         * (or a descendant in nested fo:wrapper sequence, the first of which
         *  is a child of a FO that allows mixed content) */
        FONode ancestor = this.parent;
        while (ancestor instanceof Wrapper) {
            ancestor = ancestor.getParent();
        }
        if (ancestor instanceof FObjMixed ) {
            inlineChildrenAllowed = true;
        }
    }

    /**
     * {@inheritDoc}
     * <br>XSL Content Model: marker* (#PCDATA|%inline;|%block;)*
     * <br><i>Additionally (unimplemented): "An fo:wrapper that is a child of an 
     * fo:multi-properties is only permitted to have children that would 
     * be permitted in place of the fo:multi-properties."</i>
     * 
     */
    protected void validateChildNode(Locator loc, String nsURI, String localName) 
        throws ValidationException {
        if (FO_URI.equals(nsURI)) {
            if ("marker".equals(localName)) {
                if (blockOrInlineItemFound) {
                   nodesOutOfOrderError(loc, "fo:marker", 
                        "(#PCDATA|%inline;|%block;)");
                }
            } else if (isBlockOrInlineItem(nsURI, localName)) {
                //delegate validation to parent
                FONode.validateChildNode(this.parent, loc, nsURI, localName);
                blockOrInlineItemFound = true;
            } else {
                invalidChildError(loc, nsURI, localName);
            }
        }
    }

    /** {@inheritDoc} */
    protected void addCharacters(
                char[] data, 
                int start, 
                int end, 
                PropertyList pList, 
                Locator locator) throws FOPException {
        /* Only add text if the fo:wrapper's parent allows inline children */
        if (this.inlineChildrenAllowed) {
            super.addCharacters(data, start, end, pList, locator);
        }
    }

    /** {@inheritDoc} */
    public String getLocalName() {
        return "wrapper";
    }

    /** {@inheritDoc} */
    public int getNameId() {
        return FO_WRAPPER;
    }
}