| /* |
| 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. |
| */ |
| |
| package org.apache.wiki.diff; |
| |
| import org.apache.log4j.Logger; |
| import org.apache.wiki.WikiContext; |
| import org.apache.wiki.api.core.Engine; |
| import org.apache.wiki.api.exceptions.NoRequiredPropertyException; |
| import org.apache.wiki.pages.PageManager; |
| import org.apache.wiki.providers.WikiPageProvider; |
| import org.apache.wiki.util.ClassUtil; |
| |
| import java.io.IOException; |
| import java.lang.reflect.InvocationTargetException; |
| import java.util.Properties; |
| |
| |
| /** |
| * Load, initialize and delegate to the DiffProvider that will actually do the work. |
| */ |
| public class DefaultDifferenceManager implements DifferenceManager { |
| |
| private static final Logger log = Logger.getLogger( DefaultDifferenceManager.class ); |
| |
| private DiffProvider m_provider; |
| |
| /** |
| * Creates a new DifferenceManager for the given engine. |
| * |
| * @param engine The Engine. |
| * @param props A set of properties. |
| */ |
| public DefaultDifferenceManager( final Engine engine, final Properties props ) { |
| loadProvider( props ); |
| initializeProvider( engine, props ); |
| |
| log.info( "Using difference provider: " + m_provider.getProviderInfo() ); |
| } |
| |
| private void loadProvider( final Properties props ) { |
| final String providerClassName = props.getProperty( PROP_DIFF_PROVIDER, TraditionalDiffProvider.class.getName() ); |
| try { |
| final Class< ? > providerClass = ClassUtil.findClass("org.apache.wiki.diff", providerClassName ); |
| m_provider = (DiffProvider) providerClass.getDeclaredConstructor().newInstance(); |
| } catch( final ClassNotFoundException | NoSuchMethodException | InstantiationException | IllegalAccessException | InvocationTargetException e ) { |
| log.warn("Failed loading DiffProvider, will use NullDiffProvider.", e); |
| } |
| |
| if( m_provider == null ) { |
| m_provider = new DiffProvider.NullDiffProvider(); |
| } |
| } |
| |
| |
| private void initializeProvider( final Engine engine, final Properties props ) { |
| try { |
| m_provider.initialize( engine, props ); |
| } catch( final NoRequiredPropertyException | IOException e ) { |
| log.warn( "Failed initializing DiffProvider, will use NullDiffProvider.", e ); |
| m_provider = new DiffProvider.NullDiffProvider(); //doesn't need init'd |
| } |
| } |
| |
| /** |
| * Returns valid XHTML string to be used in any way you please. |
| * |
| * @param context The Wiki Context |
| * @param firstWikiText The old text |
| * @param secondWikiText the new text |
| * @return XHTML, or empty string, if no difference detected. |
| */ |
| @Override |
| public String makeDiff( final WikiContext context, final String firstWikiText, final String secondWikiText ) { |
| String diff; |
| try { |
| diff = m_provider.makeDiffHtml( context, firstWikiText, secondWikiText ); |
| |
| if( diff == null ) { |
| diff = ""; |
| } |
| } catch( final Exception e ) { |
| diff = "Failed to create a diff, check the logs."; |
| log.warn( diff, e ); |
| } |
| return diff; |
| } |
| |
| /** |
| * Returns a diff of two versions of a page. |
| * <p> |
| * Note that the API was changed in 2.6 to provide a WikiContext object! |
| * |
| * @param context The WikiContext of the page you wish to get a diff from |
| * @param version1 Version number of the old page. If WikiPageProvider.LATEST_VERSION (-1), then uses current page. |
| * @param version2 Version number of the new page. If WikiPageProvider.LATEST_VERSION (-1), then uses current page. |
| * |
| * @return A HTML-ized difference between two pages. If there is no difference, returns an empty string. |
| */ |
| @Override |
| public String getDiff( final WikiContext context, final int version1, final int version2 ) { |
| final String page = context.getPage().getName(); |
| String page1 = context.getEngine().getManager( PageManager.class ).getPureText( page, version1 ); |
| final String page2 = context.getEngine().getManager( PageManager.class ).getPureText( page, version2 ); |
| |
| // Kludge to make diffs for new pages to work this way. |
| if( version1 == WikiPageProvider.LATEST_VERSION ) { |
| page1 = ""; |
| } |
| |
| return makeDiff( context, page1, page2 ); |
| } |
| |
| } |
| |