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: XMLHandlerConfigurator.java 1761020 2016-09-16 11:17:35Z ssteiner $ */

package org.apache.fop.render;

import org.apache.avalon.framework.configuration.Configuration;
import org.apache.avalon.framework.configuration.ConfigurationException;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import org.apache.fop.apps.FOPException;
import org.apache.fop.apps.FOUserAgent;


Configurator for XMLHandler objects.

/**
 * Configurator for XMLHandler objects.
 */
public class XMLHandlerConfigurator extends AbstractRendererConfigurator {

    
logger instance 
/** logger instance */
    protected static final Log log = LogFactory.getLog(XMLHandlerConfigurator.class);

    
Default constructor

Params:
  • userAgent – the user agent
/**
     * Default constructor
     * @param userAgent the user agent
     */
    public XMLHandlerConfigurator(FOUserAgent userAgent) {
        super(userAgent);
    }

    
Returns the configuration subtree for a specific renderer.

Params:
  • cfg – the renderer configuration
  • namespace – the namespace (i.e. the XMLHandler) for which the configuration should
                 be returned
Returns:the requested configuration subtree, null if there's no configuration
/**
     * Returns the configuration subtree for a specific renderer.
     * @param cfg the renderer configuration
     * @param namespace the namespace (i.e. the XMLHandler) for which the configuration should
     *                  be returned
     * @return the requested configuration subtree, null if there's no configuration
     */
    private Configuration getHandlerConfig(Configuration cfg, String namespace) {
        if (cfg == null || namespace == null) {
            return null;
        }
        Configuration handlerConfig = null;

        Configuration[] children = cfg.getChildren("xml-handler");
        for (Configuration aChildren : children) {
            try {
                if (aChildren.getAttribute("namespace").equals(namespace)) {
                    handlerConfig = aChildren;
                    break;
                }
            } catch (ConfigurationException e) {
                // silently pass over configurations without namespace
            }
        }
        if (log.isDebugEnabled()) {
            log.debug((handlerConfig == null ? "No" : "")
                    + "XML handler configuration found for namespace " + namespace);
        }
        return handlerConfig;
    }

    
Configures renderer context by setting the handler configuration on it.

Params:
  • context – the RendererContext (contains the user agent)
  • ns – the Namespace of the foreign object
Throws:
/**
     * Configures renderer context by setting the handler configuration on it.
     * @param context the RendererContext (contains the user agent)
     * @param ns the Namespace of the foreign object
     * @throws FOPException if configuring the target objects fails
     */
    public void configure(RendererContext context, String ns) throws FOPException {
        //Optional XML handler configuration
        Configuration cfg = userAgent.getRendererConfiguration(context.getRenderer().getMimeType());
        if (cfg != null) {
            cfg = getHandlerConfig(cfg, ns);
            if (cfg != null) {
                context.setProperty(RendererContextConstants.HANDLER_CONFIGURATION, cfg);
            }
        }
    }
}