Java tutorial
/* * This library is part of OpenCms - * the Open Source Content Management System * * Copyright (c) Alkacon Software GmbH & Co. KG (http://www.alkacon.com) * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * For further information about Alkacon Software, please see the * company website: http://www.alkacon.com * * For further information about OpenCms, please see the * project website: http://www.opencms.org * * You should have received a copy of the GNU Lesser General Public * License along with this library; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ package org.opencms.ui.dialogs.history.diff; import org.opencms.file.CmsObject; import org.opencms.file.CmsProject; import org.opencms.file.CmsResource; import org.opencms.file.CmsResourceFilter; import org.opencms.gwt.shared.CmsHistoryResourceBean; import org.opencms.gwt.shared.CmsHistoryVersion; import org.opencms.main.CmsException; import org.opencms.main.OpenCms; import org.opencms.ui.A_CmsUI; import org.opencms.ui.util.table.CmsBeanTableBuilder; import org.opencms.workplace.comparison.CmsAttributeComparison; import java.util.List; import com.google.common.base.Objects; import com.google.common.base.Optional; import com.google.common.base.Predicate; import com.google.common.collect.Collections2; import com.google.common.collect.Lists; import com.vaadin.ui.Component; import com.vaadin.ui.Panel; import com.vaadin.ui.Table; import com.vaadin.ui.VerticalLayout; /** * Abstract super class for displaying differences between a set of properties / attributes.<p> */ public abstract class A_CmsAttributeDiff implements I_CmsDiffProvider { /** * Predicate used to check if an attribute comparison bean actually represents a difference.<p> */ public static class IsAttributeDifference implements Predicate<CmsAttributeComparison> { /** * @see com.google.common.base.Predicate#apply(java.lang.Object) */ public boolean apply(CmsAttributeComparison input) { return !Objects.equal(input.getVersion1(), input.getVersion2()); } } /** CSS class to mark the compare table. */ private static final String COMPARE_TABLE_MARKER = "cms-compare-table-marker"; /** * Only selects the attributes comparisons that actually represent differences.<p> * * @param comps the attribute comparisons * * @return the list of attribute comparisons which correspond to actual differences */ public static List<CmsAttributeComparison> filterDifferent(List<CmsAttributeComparison> comps) { return Lists.newArrayList(Collections2.filter(comps, new IsAttributeDifference())); } /** * Builds a version string which can be used by CmsResourceComparison from a history resource bean.<p> * * This is not really a user-readable string, it is meant for internal usage. * * @param bean the history resource bean * @return the version string */ public static String getVersionString(CmsHistoryResourceBean bean) { if (bean.getVersion().getVersionNumber() != null) { return bean.getVersion().getVersionNumber().toString(); } else if (bean.getVersion().isOffline()) { return "0"; } else { return "-1"; } } /** * Reads a historical resource for a history resource bean.<p> * * @param cms the CMS context * @param bean the history resource bean * @return the historical resource * * @throws CmsException if something goes wrong */ public static CmsResource readResource(CmsObject cms, CmsHistoryResourceBean bean) throws CmsException { CmsHistoryVersion versionBean = bean.getVersion(); if (versionBean.getVersionNumber() != null) { return (CmsResource) (cms.readResource(bean.getStructureId(), versionBean.getVersionNumber().intValue())); } else { if (versionBean.isOnline()) { CmsObject onlineCms = OpenCms.initCmsObject(cms); onlineCms.getRequestContext().setCurrentProject(cms.readProject(CmsProject.ONLINE_PROJECT_ID)); return onlineCms.readResource(bean.getStructureId(), CmsResourceFilter.IGNORE_EXPIRATION); } else { return cms.readResource(bean.getStructureId(), CmsResourceFilter.IGNORE_EXPIRATION); } } } /** * @see org.opencms.ui.dialogs.history.diff.I_CmsDiffProvider#diff(org.opencms.file.CmsObject, org.opencms.gwt.shared.CmsHistoryResourceBean, org.opencms.gwt.shared.CmsHistoryResourceBean) */ public Optional<Component> diff(CmsObject cms, CmsHistoryResourceBean v1, CmsHistoryResourceBean v2) throws CmsException { List<CmsAttributeComparison> attrCompare = getDifferences(cms, v1, v2); if (attrCompare.isEmpty()) { return Optional.absent(); } List<CmsPropertyCompareBean> compareBeans = Lists.newArrayList(); for (CmsAttributeComparison comp : attrCompare) { compareBeans.add(new CmsPropertyCompareBean(comp)); } CmsBeanTableBuilder<CmsPropertyCompareBean> builder = CmsBeanTableBuilder .newInstance(CmsPropertyCompareBean.class, A_CmsUI.get().getDisplayType().toString()); builder.setMacroResolver(new CmsVersionMacroResolver(v1, v2)); Table table = builder.buildTable(compareBeans); table.setSortEnabled(false); table.setWidth("100%"); table.setPageLength(Math.min(12, compareBeans.size())); table.setStyleName(COMPARE_TABLE_MARKER); VerticalLayout vl = new VerticalLayout(); vl.setMargin(true); vl.addComponent(table); Panel panel = new Panel(getCaption()); panel.setContent(vl); return Optional.fromNullable((Component) panel); } /** * Gets the caption.<p> * * @return the caption */ public abstract String getCaption(); /** * Gets the attribute comparison beans representing the differences.<p> * * @param cms the CMS context * @param v1 history bean representing the first version * @param v2 history bean representing the second version * @return the list of attribute comparisons for the given versions * * @throws CmsException if something goes wrong */ public abstract List<CmsAttributeComparison> getDifferences(CmsObject cms, CmsHistoryResourceBean v1, CmsHistoryResourceBean v2) throws CmsException; }