| /* |
| * 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.el.lang; |
| |
| import javax.el.ValueExpression; |
| import javax.el.VariableMapper; |
| |
| public class VariableMapperFactory extends VariableMapper { |
| |
| private final VariableMapper target; |
| private VariableMapper momento; |
| |
| public VariableMapperFactory(VariableMapper target) { |
| if (target == null) { |
| throw new NullPointerException("Target VariableMapper cannot be null"); |
| } |
| this.target = target; |
| } |
| |
| public VariableMapper create() { |
| return this.momento; |
| } |
| |
| @Override |
| public ValueExpression resolveVariable(String variable) { |
| ValueExpression expr = this.target.resolveVariable(variable); |
| if (expr != null) { |
| if (this.momento == null) { |
| this.momento = new VariableMapperImpl(); |
| } |
| this.momento.setVariable(variable, expr); |
| } |
| return expr; |
| } |
| |
| @Override |
| public ValueExpression setVariable(String variable, ValueExpression expression) { |
| throw new UnsupportedOperationException("Cannot Set Variables on Factory"); |
| } |
| } |