Java tutorial
/* * (C) Copyright 2013 Nuxeo SA (http://nuxeo.com/) and others. * * Licensed 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. * * Contributors: * Anahide Tchertchian */ package org.nuxeo.ecm.platform.actions.jsf; import javax.el.ELContext; import javax.el.ELException; import javax.el.ExpressionFactory; import javax.el.ValueExpression; import javax.el.VariableMapper; import javax.faces.context.FacesContext; import org.apache.commons.lang.StringUtils; import org.nuxeo.ecm.core.api.DocumentModel; import org.nuxeo.ecm.core.api.NuxeoPrincipal; import org.nuxeo.ecm.platform.actions.AbstractActionContext; import org.nuxeo.ecm.platform.actions.ActionContext; import org.nuxeo.ecm.platform.ui.web.util.SeamContextHelper; /** * @since 5.7.3 */ public class JSFActionContext extends AbstractActionContext implements ActionContext { private static final long serialVersionUID = 1L; protected final ELContext originalContext; protected final ExpressionFactory expressionFactory; public JSFActionContext(FacesContext faces) { super(); this.originalContext = faces.getELContext(); this.expressionFactory = faces.getApplication().getExpressionFactory(); } public JSFActionContext(ELContext originalContext, ExpressionFactory expressionFactory) { super(); this.originalContext = originalContext; this.expressionFactory = expressionFactory; } @Override public boolean checkCondition(String expression) throws ELException { if (StringUtils.isBlank(expression) || (expression != null && StringUtils.isBlank(expression.trim()))) { return false; } String expr = expression.trim(); // compatibility code, as JEXL could resolve that kind of expression: // detect if expression is in brackets #{}, otherwise add it if (!expr.startsWith("#{") && !expr.startsWith("${") // don't confuse error messages in case of simple mistakes in the // expression && !expr.endsWith("}")) { expr = "#{" + expr + "}"; } ELContext finalContext = new JSFELContext(originalContext); VariableMapper vm = finalContext.getVariableMapper(); // init default variables ValueExpression documentExpr = expressionFactory.createValueExpression(getCurrentDocument(), DocumentModel.class); ValueExpression userExpr = expressionFactory.createValueExpression(getCurrentPrincipal(), NuxeoPrincipal.class); vm.setVariable("actionContextDocument", documentExpr); // add variables originally exposed by the action framework, // do not add aliases currentDocument and currentUser here as they // should already be available in this JSF context vm.setVariable("document", documentExpr); vm.setVariable("principal", userExpr); // get custom context from ActionContext for (String key : localVariables.keySet()) { vm.setVariable(key, expressionFactory.createValueExpression(getLocalVariable(key), Object.class)); } // expose Seam context for compatibility, although available its // components should be natively exposed in this JSF context putLocalVariable("SeamContext", new SeamContextHelper()); // evaluate expression ValueExpression ve = expressionFactory.createValueExpression(finalContext, expr, Boolean.class); return Boolean.TRUE.equals(ve.getValue(finalContext)); } }