001 /* 002 * Licensed to the Apache Software Foundation (ASF) under one 003 * or more contributor license agreements. See the NOTICE file 004 * distributed with this work for additional information 005 * regarding copyright ownership. The ASF licenses this file 006 * to you under the Apache License, Version 2.0 (the 007 * "License"); you may not use this file except in compliance 008 * with the License. You may obtain a copy of the License at 009 * 010 * http://www.apache.org/licenses/LICENSE-2.0 011 * 012 * Unless required by applicable law or agreed to in writing, 013 * software distributed under the License is distributed on an 014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 015 * KIND, either express or implied. See the License for the 016 * specific language governing permissions and limitations 017 * under the License. 018 */ 019 020 package org.apache.myfaces.tobago.util; 021 022 import javax.faces.application.Application; 023 import javax.faces.context.FacesContext; 024 import javax.faces.el.VariableResolver; 025 import javax.faces.el.ValueBinding; 026 027 public class VariableResolverUtil { 028 029 private VariableResolverUtil() { 030 } 031 032 public static Object resolveVariable(FacesContext context, String variable) { 033 Application application = context.getApplication(); 034 VariableResolver variableResolver = application.getVariableResolver(); 035 return variableResolver.resolveVariable(context, variable); 036 } 037 038 /** 039 * Clears the value of the variable. 040 * Useful for cleaning up e.g. a session or application variable 041 * to save memory without the knowledge of the scope. 042 * Also useful to enforce a new creation of a managed-bean. 043 * 044 * @param context 045 * @param variable 046 */ 047 public static void clearVariable(FacesContext context, String variable) { 048 Application application = context.getApplication(); 049 ValueBinding valueBinding = application.createValueBinding("#{" + variable + "}"); 050 valueBinding.setValue(context, null); 051 } 052 }