    001package org.apache.turbine.services.template.mapper;
    002
    003
    004/*
    005 * Licensed to the Apache Software Foundation (ASF) under one
    006 * or more contributor license agreements.  See the NOTICE file
    007 * distributed with this work for additional information
    008 * regarding copyright ownership.  The ASF licenses this file
    009 * to you under the Apache License, Version 2.0 (the
    010 * "License"); you may not use this file except in compliance
    011 * with the License.  You may obtain a copy of the License at
    012 *
    013 *   http://www.apache.org/licenses/LICENSE-2.0
    014 *
    015 * Unless required by applicable law or agreed to in writing,
    016 * software distributed under the License is distributed on an
    017 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
    018 * KIND, either express or implied.  See the License for the
    019 * specific language governing permissions and limitations
    020 * under the License.
    021 */
    022
    023
    024import java.util.ArrayList;
    025import java.util.Arrays;
    026import java.util.List;
    027
    028import org.apache.commons.lang.StringUtils;
    029import org.apache.commons.logging.Log;
    030import org.apache.commons.logging.LogFactory;
    031import org.apache.turbine.services.TurbineServices;
    032import org.apache.turbine.services.template.TemplateEngineService;
    033import org.apache.turbine.services.template.TemplateService;
    034
    035/**
    036 * This mapper is responsible for the lookup of templates for the Layout
    037 * It tries to look in various packages for a match:
    038 *
    039 * 1. about,directions,Driving.vm      &lt;- exact match
    040 * 2. about,directions,Default.vm      &lt;- package match, Default name
    041 * 3. about,Default.vm                 &lt;- stepping up in the hierarchy
    042 * 4. Default.vm                       &lt;- The name configured as default.layout.template
    043 *                                        in the corresponding Templating Engine
    044
    045 *
    046 * @author <a href="mailto:hps@intermeta.de">Henning P. Schmiedehausen</a>
    047 * @version $Id: LayoutTemplateMapper.java 1723699 2016-01-08 11:29:21Z tv $
    048 */
    049
    050public class LayoutTemplateMapper
    051    extends BaseTemplateMapper
    052    implements Mapper
    053{
    054    /** Logging */
    055    private static Log log = LogFactory.getLog(LayoutTemplateMapper.class);
    056
    057    /**
    058     * Default C'tor. If you use this C'tor, you must use
    059     * the bean setter to set the various properties needed for
    060     * this mapper before first usage.
    061     */
    062    public LayoutTemplateMapper()
    063    {
    064        // empty
    065    }
    066
    067    /**
    068     * Look for a given Template, then try the
    069     * defaults until we hit the root.
    070     *
    071     * @param template The template name.
    072     * @return The parsed module name.
    073     */
    074    @Override
    075    public String doMapping(String template)
    076    {
    077        log.debug("doMapping(" + template + ")");
    078        // Copy our elements into an array
    079        List<String> components
    080            = new ArrayList<String>(Arrays.asList(StringUtils.split(
    081                                              template,
    082                                              String.valueOf(TemplateService.TEMPLATE_PARTS_SEPARATOR))));
    083        int componentSize = components.size() - 1 ;
    084
    085        // This method never gets an empty string passed.
    086        // So this is never < 0
    087        String templateName = components.get(componentSize);
    088        components.remove(componentSize--);
    089
    090        log.debug("templateName is " + templateName);
    091
    092        // Last element decides, which template Service to use...
    093        TemplateService templateService = (TemplateService)TurbineServices.getInstance().getService(TemplateService.SERVICE_NAME);
    094        TemplateEngineService tes = templateService.getTemplateEngineService(templateName);
    095
    096        if (tes == null)
    097        {
    098            return null;
    099        }
    100
    101        // We're, after all, a Layout Template Mapper...
    102        String defaultName = templateService.getDefaultLayoutTemplateName(templateName);
    103
    104        // This is an optimization. If the name we're looking for is
    105        // already the default name for the template, don't do a "first run"
    106        // which looks for an exact match.
    107        boolean firstRun = !templateName.equals(defaultName);
    108
    109        for(;;)
    110        {
    111            String templatePackage = StringUtils.join(components.iterator(), String.valueOf(separator));
    112
    113            log.debug("templatePackage is now: " + templatePackage);
    114
    115            StringBuilder testName = new StringBuilder();
    116
    117            if (!components.isEmpty())
    118            {
    119                testName.append(templatePackage);
    120                testName.append(separator);
    121            }
    122
    123            testName.append((firstRun)
    124                ? templateName
    125                : defaultName);
    126
    127            // But the Templating service must look for the name with prefix
    128            StringBuilder templatePath = new StringBuilder();
    129            if (StringUtils.isNotEmpty(prefix))
    130            {
    131                templatePath.append(prefix);
    132                templatePath.append(separator);
    133            }
    134            templatePath.append(testName);
    135
    136            log.debug("Looking for " + templatePath);
    137
    138            if (tes.templateExists(templatePath.toString()))
    139            {
    140                log.debug("Found it, returning " + testName);
    141                return testName.toString();
    142            }
    143
    144            if (firstRun)
    145            {
    146                firstRun = false;
    147            }
    148            else
    149            {
    150                // We're no longer on the first Run (so we
    151                // already tested the "Default" template)
    152                // and the package is empty (we've hit the
    153                // root. So we now break the endless loop.
    154                if (components.isEmpty())
    155                {
    156                    break; // for(;;)
    157                }
    158                // We still have components. Remove the
    159                // last one and go through the loop again.
    160                components.remove(componentSize--);
    161            }
    162        }
    163
    164        log.debug("Returning default");
    165        return getDefaultName(template);
    166    }
    167}