    001package org.apache.turbine.util.template;
    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 org.apache.commons.logging.Log;
    025import org.apache.commons.logging.LogFactory;
    026import org.apache.turbine.modules.NavigationLoader;
    027import org.apache.turbine.services.TurbineServices;
    028import org.apache.turbine.services.template.TemplateService;
    029import org.apache.turbine.util.RunData;
    030
    031/**
    032 * Returns output of a Navigation module.  An instance of this is
    033 * placed in the WebMacro context by the WebMacroSiteLayout.  This
    034 * allows template authors to set the navigation template they'd like
    035 * to place in their templates.  Here's how it's used in a
    036 * template:
    037 *
    038 * <p><code>
    039 * $navigation.setTemplate("admin_navigation.wm")
    040 * </code>
    041 *
    042 * @author <a href="mbryson@mont.mindspring.com">Dave Bryson</a>
    043 * @version $Id: TemplateNavigation.java 1723699 2016-01-08 11:29:21Z tv $
    044 */
    045public class TemplateNavigation
    046{
    047    /** Logging */
    048    private static Log log = LogFactory.getLog(TemplateNavigation.class);
    049
    050    /* The RunData object. */
    051    private RunData data;
    052
    053    /* The name of the navigation template. */
    054    private String template = null;
    055
    056    /**
    057     * Constructor
    058     *
    059     * @param data A Turbine RunData object.
    060     */
    061    public TemplateNavigation(RunData data)
    062    {
    063        this.data = data;
    064    }
    065
    066    /**
    067     * Set the template.
    068     *
    069     * @param template A String with the name of the navigation
    070     * template.
    071     * @return A TemplateNavigation (self).
    072     */
    073    public TemplateNavigation setTemplate(String template)
    074    {
    075        log.debug("setTemplate(" + template + ")");
    076        this.template = template;
    077        return this;
    078    }
    079
    080    /**
    081     * Builds the output of the navigation template.
    082     *
    083     * @return A String.
    084     */
    085    @Override
    086    public String toString()
    087    {
    088        String module = null;
    089        String returnValue = null;
    090
    091        try
    092        {
    093            if (template == null)
    094            {
    095                returnValue = "Navigation Template is null (Might be unset)";
    096                throw new Exception(returnValue);
    097            }
    098
    099            data.getTemplateInfo().setNavigationTemplate(template);
    100            TemplateService templateService = (TemplateService)TurbineServices.getInstance().getService(TemplateService.SERVICE_NAME);
    101            module = templateService.getNavigationName(template);
    102
    103            if (module == null)
    104            {
    105                returnValue = "Template Service returned null for Navigation Template " + template;
    106                throw new Exception(returnValue);
    107            }
    108
    109            returnValue = NavigationLoader.getInstance().eval(data, module);
    110        }
    111        catch (Exception e)
    112        {
    113            if (returnValue == null)
    114            {
    115                returnValue = "Error processing navigation template: "
    116                        + template + ", using module: " + module;
    117            }
    118            log.error(returnValue, e);
    119        }
    120
    121        return returnValue;
    122    }
    123}