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/* * Copyright 2002-2017 the original author or authors. * * 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 * * https://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.springframework.beans.factory.config; import org.springframework.beans.BeansException; import org.springframework.lang.Nullable; /** * Strategy interface for resolving a value through evaluating it * as an expression, if applicable. * * <p>A raw {@link org.springframework.beans.factory.BeanFactory} does not * contain a default implementation of this strategy. However, * {@link org.springframework.context.ApplicationContext} implementations * will provide expression support out of the box. * * @author Juergen Hoeller * @since 3.0 */ public interface BeanExpressionResolver { /** * Evaluate the given value as an expression, if applicable; * return the value as-is otherwise. * @param value the value to check * @param evalContext the evaluation context * @return the resolved value (potentially the given value as-is) * @throws BeansException if evaluation failed */ @Nullable Object evaluate(@Nullable String value, BeanExpressionContext evalContext) throws BeansException; }