001 package org.apache.myfaces.tobago.util; 002 003 /* 004 * Licensed to the Apache Software Foundation (ASF) under one or more 005 * contributor license agreements. See the NOTICE file distributed with 006 * this work for additional information regarding copyright ownership. 007 * The ASF licenses this file to You under the Apache License, Version 2.0 008 * (the "License"); you may not use this file except in compliance with 009 * the License. You may obtain a copy of the License at 010 * 011 * http://www.apache.org/licenses/LICENSE-2.0 012 * 013 * Unless required by applicable law or agreed to in writing, software 014 * distributed under the License is distributed on an "AS IS" BASIS, 015 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 016 * See the License for the specific language governing permissions and 017 * limitations under the License. 018 */ 019 020 import org.apache.myfaces.tobago.context.ClientProperties; 021 022 import javax.faces.application.Application; 023 import javax.faces.context.FacesContext; 024 import javax.faces.el.ValueBinding; 025 import javax.faces.el.VariableResolver; 026 027 public final class VariableResolverUtils { 028 029 private VariableResolverUtils() { 030 // utils class 031 } 032 033 /** 034 * Returns the requested object configured in the faces-config or from library. 035 */ 036 public static Object resolveVariable(FacesContext context, String variable) { 037 // TODO: JSF 1.2 038 // if (FacesVersion.supports12()) { 039 // final ELContext elContext = context.getELContext(); 040 // return elContext.getELResolver().getValue(elContext, null, variable); 041 // } else { 042 final Application application = context.getApplication(); 043 final VariableResolver variableResolver = application.getVariableResolver(); 044 return variableResolver.resolveVariable(context, variable); 045 // } 046 } 047 048 /** 049 * Returns the ClientProperties object configured in the faces-config. 050 */ 051 public static ClientProperties resolveClientProperties(FacesContext facesContext) { 052 return (ClientProperties) resolveVariable(facesContext, ClientProperties.MANAGED_BEAN_NAME); 053 } 054 055 /** 056 * Clears the value of the variable. 057 * Useful for cleaning up e.g. a session or application variable 058 * to save memory without the knowledge of the scope. 059 * Also useful to enforce a new creation of a managed-bean. 060 */ 061 public static void clearVariable(FacesContext context, String variable) { 062 // TODO: JSF 1.2 063 // if (FacesVersion.supports12()) { 064 // final ELContext elContext = context.getELContext(); 065 // elContext.getELResolver().setValue(elContext, null, variable, null); 066 // } else { 067 final Application application = context.getApplication(); 068 final ValueBinding valueBinding = application.createValueBinding("#{" + variable + "}"); 069 valueBinding.setValue(context, null); 070 // } 071 } 072 }