http://xmlgraphics.apache.org/fop/: Apache FOP (Formatting Objects Processor) is the world's first print formatter driven by XSL formatting objects (XSL-FO) and the world's first output independent formatter. It is a Java application that reads a formatting object (FO) tree and renders the resulting pages to a specified output. Output formats currently supported include PDF, PCL, PS, AFP, TIFF, PNG, SVG, XML (area tree representation), Print, AWT and TXT. The primary output target is PDF. (Apache Software Foundation) 
/*
 * 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: PageDimensionMaker.java 992386 2010-09-03 17:26:28Z vhennebert $ */

package org.apache.fop.fo.properties;

import org.apache.fop.fo.Constants;
import org.apache.fop.fo.FObj;
import org.apache.fop.fo.PropertyList;
import org.apache.fop.fo.expr.PropertyException;


Custom Maker for page-height / page-width

/**
 * Custom Maker for page-height / page-width
 *
 */
public class PageDimensionMaker extends LengthProperty.Maker {

    
Constructor

Params:
  • propId –    the property Id
/**
     * Constructor
     *
     * @param propId    the property Id
     */
    public PageDimensionMaker(int propId) {
        super(propId);
    }

    
Check the value of the page-width / page-height property.
Return the default or user-defined fallback in case the value
was specified as "auto"

Params:
  • subpropId –  The subproperty id of the property being retrieved.
       Is 0 when retrieving a base property.
  • propertyList – The PropertyList object being built for this FO.
  • tryInherit – true if inherited properties should be examined.
  • tryDefault – true if the default value should be returned.
Throws:
See Also:
Returns:the property
/**
     * Check the value of the page-width / page-height property.
     * Return the default or user-defined fallback in case the value
     * was specified as "auto"
     * @param subpropId  The subproperty id of the property being retrieved.
     *        Is 0 when retrieving a base property.
     * @param propertyList The PropertyList object being built for this FO.
     * @param tryInherit true if inherited properties should be examined.
     * @param tryDefault true if the default value should be returned.
     * @return the property
     * @throws PropertyException if a property exception occurs
     * @see PropertyMaker#get(int, PropertyList, boolean, boolean)
     */
    public Property get(int subpropId, PropertyList propertyList,
                        boolean tryInherit, boolean tryDefault)
            throws PropertyException {

        Property p = super.get(0, propertyList, tryInherit, tryDefault);
        FObj fo = propertyList.getFObj();
        String fallbackValue = (propId == Constants.PR_PAGE_HEIGHT)
            ? fo.getUserAgent().getPageHeight()
                    : fo.getUserAgent().getPageWidth();

        if (p.getEnum() == Constants.EN_INDEFINITE) {
            int otherId = (propId == Constants.PR_PAGE_HEIGHT)
                ? Constants.PR_PAGE_WIDTH : Constants.PR_PAGE_HEIGHT;
            int writingMode = propertyList.get(Constants.PR_WRITING_MODE).getEnum();
            int refOrientation = propertyList.get(Constants.PR_REFERENCE_ORIENTATION)
                        .getNumeric().getValue();
            if (propertyList.getExplicit(otherId) != null
                    && propertyList.getExplicit(otherId).getEnum() == Constants.EN_INDEFINITE) {
                //both set to "indefinite":
                //determine which one of the two defines the dimension
                //in block-progression-direction, and set the other to
                //"auto"
                if ((writingMode != Constants.EN_TB_RL
                        && (refOrientation == 0
                                || refOrientation == 180
                                || refOrientation == -180))
                     || (writingMode == Constants.EN_TB_RL
                             && (refOrientation == 90
                                     || refOrientation == 270
                                     || refOrientation == -270))) {
                    //set page-width to "auto" = use the fallback from FOUserAgent
                    if (propId == Constants.PR_PAGE_WIDTH) {
                        Property.log.warn("Both page-width and page-height set to "
                                + "\"indefinite\". Forcing page-width to \"auto\"");
                        return make(propertyList, fallbackValue, fo);
                    }
                } else {
                    //set page-height to "auto" = use fallback from FOUserAgent
                    Property.log.warn("Both page-width and page-height set to "
                            + "\"indefinite\". Forcing page-height to \"auto\"");
                    if (propId == Constants.PR_PAGE_HEIGHT) {
                        return make(propertyList, fallbackValue, fo);
                    }
                }
            }
        } else if (p.isAuto()) {
            return make(propertyList, fallbackValue, fo);
        }

        return p;
    }
}