Java tutorial
/* * 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.wicket.devutils.debugbar; import java.util.ArrayList; import java.util.List; import org.apache.wicket.Application; import org.apache.wicket.AttributeModifier; import org.apache.wicket.Component; import org.apache.wicket.MetaDataKey; import org.apache.wicket.devutils.DevUtilsPanel; import org.apache.wicket.markup.head.CssHeaderItem; import org.apache.wicket.markup.head.IHeaderResponse; import org.apache.wicket.markup.head.JavaScriptHeaderItem; import org.apache.wicket.markup.head.OnDomReadyHeaderItem; import org.apache.wicket.markup.html.WebMarkupContainer; import org.apache.wicket.markup.html.image.Image; import org.apache.wicket.markup.html.list.ListItem; import org.apache.wicket.markup.html.list.ListView; import org.apache.wicket.model.IModel; import org.apache.wicket.request.resource.CssResourceReference; import org.apache.wicket.request.resource.JavaScriptResourceReference; import org.apache.wicket.request.resource.PackageResourceReference; import org.apache.wicket.util.lang.Args; /** * The debug bar is for use during development. It allows contributors to add useful functions or * data, making them readily accessible to the developer.<br /> * <br /> * To use it, simply add it to your base page so that all of your pages automatically have it.<br /> * * <br /> * <code> * Java: * add(new DebugBar("debug")); * * HTML: * <div wicket:id="debug"></div> * </code> * * <br /> * You can also add your own information to the bar by creating a {@link IDebugBarContributor} and * registering it with the debug bar. * * <p>The debug bar uses CSS absolute positioning to appear in the top-right corner of the page. * <strong>Important</strong>: if there is an element with a z-index in this part of your page, the DebugBar will need a higher * "z-index" style value to show up. Or you can use different position for it. See wicket-debugbar.css.</p> * * @author Jeremy Thomerson <jthomerson@apache.org> * @see IDebugBarContributor */ public class DebugBar extends DevUtilsPanel { private static final long serialVersionUID = 1L; private static final MetaDataKey<List<IDebugBarContributor>> CONTRIBS_META_KEY = new MetaDataKey<List<IDebugBarContributor>>() { private static final long serialVersionUID = 1L; }; /** * Construct. * <p/> * Create debug bar (initially expanded) * * @param id * component id * * @see #DebugBar(String, boolean) */ public DebugBar(final String id) { this(id, true); } /** * Construct. * * @param id * component id * @param initiallyExpanded * {@code true} to show debug bar initially expanded * * @see #DebugBar(String) */ public DebugBar(final String id, boolean initiallyExpanded) { super(id); setMarkupId("wicketDebugBar"); setOutputMarkupId(true); add(AttributeModifier.replace("class", new IModel<String>() { private static final long serialVersionUID = 1L; @Override public String getObject() { return "wicketDebugBar" + (DebugBar.this.hasErrorMessage() ? "Error" : ""); } })); add(new Image("logo", new PackageResourceReference(DebugBar.class, "wicket.png"))); add(contentSection("content", initiallyExpanded)); } /** * Positions the DebugBar at the bottom of the page * @return */ public DebugBar positionBottom() { add(AttributeModifier.append("class", "bottom")); return this; } private Component contentSection(final String id, boolean initiallyExpanded) { WebMarkupContainer section = new WebMarkupContainer(id); if (!initiallyExpanded) { section.add(AttributeModifier.append("style", "display:none").setSeparator(";")); } List<IDebugBarContributor> contributors = getContributors(getApplication()); section.add(new ListView<IDebugBarContributor>("contributors", contributors) { private static final long serialVersionUID = 1L; @Override protected void populateItem(final ListItem<IDebugBarContributor> item) { IDebugBarContributor contrib = item.getModelObject(); Component comp = contrib.createComponent("contrib", DebugBar.this); if (comp == null) { // some contributors only add information to the debug bar // and don't actually create a contributed component item.setVisibilityAllowed(false); } else { item.add(comp); } } }); section.add(new Image("removeImg", new PackageResourceReference(DebugBar.class, "remove.png"))); return section; } @Override public boolean isVisible() { return getApplication().getDebugSettings().isDevelopmentUtilitiesEnabled(); } @Override public void renderHead(final IHeaderResponse response) { response.render( CssHeaderItem.forReference(new CssResourceReference(DebugBar.class, "wicket-debugbar.css"))); response.render(JavaScriptHeaderItem .forReference(new JavaScriptResourceReference(DebugBar.class, "wicket-debugbar.js"))); response.render(OnDomReadyHeaderItem.forScript("wicketDebugBarCheckState()")); } /** * Register your own custom contributor that will be part of the debug bar. You must have the * context of an application for this thread at the time of calling this method. * * @param contrib * custom contributor - can not be null */ public static void registerContributor(final IDebugBarContributor contrib) { registerContributor(contrib, Application.get()); } /** * Register your own custom contributor that will be part of the debug bar. You must have the * context of an application for this thread at the time of calling this method. * * @param application * @param contrib * custom contributor - can not be null */ public static void registerContributor(final IDebugBarContributor contrib, final Application application) { Args.notNull(contrib, "contrib"); List<IDebugBarContributor> contributors = getContributors(application); contributors.add(contrib); setContributors(contributors, application); } public static List<IDebugBarContributor> getContributors(final Application application) { List<IDebugBarContributor> list = application.getMetaData(CONTRIBS_META_KEY); return list == null ? new ArrayList<IDebugBarContributor>() : list; } public static void setContributors(List<IDebugBarContributor> contributors, Application application) { Args.notNull(application, "application"); application.setMetaData(CONTRIBS_META_KEY, contributors); } }