Java tutorial
/*************************************************************** * This file is part of the [fleXive](R) framework. * * Copyright (c) 1999-2014 * UCS - unique computing solutions gmbh (http://www.ucs.at) * All rights reserved * * The [fleXive](R) project is free software; you can redistribute * it and/or modify it under the terms of the GNU Lesser General Public * License version 2.1 or higher as published by the Free Software Foundation. * * The GNU Lesser General Public License can be found at * http://www.gnu.org/licenses/lgpl.html. * A copy is found in the textfile LGPL.txt and important notices to the * license from the author are found in LICENSE.txt distributed with * these libraries. * * 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 General Public License for more details. * * For further information about UCS - unique computing solutions gmbh, * please see the company website: http://www.ucs.at * * For further information about [fleXive](R), please see the * project website: http://www.flexive.org * * * This copyright notice MUST APPEAR in all copies of the file! ***************************************************************/ package com.flexive.faces.components.content; import com.flexive.faces.FxJsfComponentUtils; import com.flexive.shared.exceptions.FxRuntimeException; import com.flexive.shared.value.FxString; import com.flexive.shared.value.FxValue; import com.flexive.shared.value.mapper.InputMapper; import com.flexive.shared.value.renderer.FxValueFormatter; import com.sun.facelets.FaceletContext; import com.sun.facelets.el.VariableMapperWrapper; import com.sun.facelets.tag.TagAttribute; import com.sun.facelets.tag.TagConfig; import com.sun.facelets.tag.TagHandler; import org.apache.commons.lang.StringUtils; import javax.el.ELException; import javax.el.ExpressionFactory; import javax.el.ValueExpression; import javax.el.VariableMapper; import javax.faces.FacesException; import javax.faces.component.UIComponent; import java.io.IOException; /** * A facelets handler that renders a complete form element for editing or displaying * a property of a content instance provided by {@link FxContentView}. The output template * is provided by fxValueInputRow.xhtml (the component template of fx:fxValueInputRow). * A custom template can be specified with the <code>template</code> parameter. * * @author Daniel Lichtenberger (daniel.lichtenberger@flexive.com), UCS - unique computing solutions gmbh (http://www.ucs.at) * @version $Rev$ */ public class FxValueHandler extends TagHandler { private static final String TEMPLATE_ROOT = "templates/"; private String template = "fxValueInputRow.xhtml"; public FxValueHandler(TagConfig config) { super(config); } @Override public void apply(FaceletContext ctx, UIComponent parent) throws IOException, FacesException, ELException { final String var; try { if (this.getAttribute("var") == null) { // no variable name specified, use enclosing content view if (!(parent instanceof FxContentView)) { throw new FacesException( "Facelet parent is no FxContentView instance and \"var\" attribute not specified."); } var = ((FxContentView) parent).getVar(); } else { // use a custom variable name var = this.getAttribute("var").getValue(ctx); } } catch (FxRuntimeException e) { throw new FacesException("The fx:value component must be embedded in a fx:content instance."); } final boolean isNewValue = this.getAttribute("new") != null && Boolean.valueOf(this.getAttribute("new").getValue(ctx)); final VariableMapper origMapper = ctx.getVariableMapper(); final VariableMapperWrapper mapper = new VariableMapperWrapper(origMapper); try { ctx.setVariableMapper(mapper); // get property attribute final String property; final TagAttribute propertyAttribute = this.getAttribute("property"); if (propertyAttribute != null) { final ValueExpression propertyExpression = propertyAttribute.getValueExpression(ctx, String.class); property = (String) propertyExpression.getValue(ctx); } else { property = null; } FxJsfComponentUtils.requireAttribute("fx:value", "property", property); // assign id, label/labelKey and value based on the enclosing FxContentView instance final ExpressionFactory expressionFactory = ctx.getExpressionFactory(); mapper.setVariable("id", expressionFactory.createValueExpression(StringUtils.replace(property, "/", "_"), String.class)); if (this.getAttribute("labelKey") == null) { // use property label mapper.setVariable("label", expressionFactory.createValueExpression(ctx, FxContentView.getExpression(var, property, "label"), FxString.class)); } else { // use provided message key assignAttribute(ctx, mapper, "labelKey", String.class); } // retrieve content from content view mapper.setVariable("value", expressionFactory.createValueExpression(ctx, FxContentView.getExpression(var, property, isNewValue ? "new" : null), FxValue.class)); // passthrough other template attributes assignAttribute(ctx, mapper, "inputMapper", InputMapper.class); assignAttribute(ctx, mapper, "onchange", String.class); assignAttribute(ctx, mapper, "readOnly", Boolean.class); assignAttribute(ctx, mapper, "decorate", Boolean.class); assignAttribute(ctx, mapper, "filter", Boolean.class); assignAttribute(ctx, mapper, "forceLineInput", Boolean.class); assignAttribute(ctx, mapper, "newLine", Boolean.class); assignAttribute(ctx, mapper, "valueFormatter", FxValueFormatter.class); assignAttribute(ctx, mapper, "containerDivClass", String.class); assignAttribute(ctx, mapper, "autocompleteHandler", String.class); assignAttribute(ctx, mapper, "disableMultiLanguage", Boolean.class); assignAttribute(ctx, mapper, "disableLytebox", Boolean.class); assignAttribute(ctx, mapper, "tooltip", String.class); assignAttribute(ctx, mapper, "tooltipKey", String.class); // TODO: cache templates/use a facelet ResourceResolver to encapsulate this ctx.includeFacelet(parent, Thread.currentThread().getContextClassLoader().getResource(TEMPLATE_ROOT + template)); } finally { ctx.setVariableMapper(origMapper); } } private void assignAttribute(FaceletContext ctx, VariableMapper mapper, String name, Class<?> expectedClass) { final TagAttribute attribute = getAttribute(name); if (attribute != null) { mapper.setVariable(name, attribute.getValueExpression(ctx, expectedClass)); } } /** * Sets the template name (relative to /WEB-INF/templates). * * @param template the template name (relative to /WEB-INF/templates). */ public void setTemplate(String template) { this.template = template; } }