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/* * Copyright 2002-2018 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.lang.Nullable; import org.springframework.util.Assert; /** * Context object for evaluating an expression within a bean definition. * * @author Juergen Hoeller * @since 3.0 */ public class BeanExpressionContext { private final ConfigurableBeanFactory beanFactory; @Nullable private final Scope scope; public BeanExpressionContext(ConfigurableBeanFactory beanFactory, @Nullable Scope scope) { Assert.notNull(beanFactory, "BeanFactory must not be null"); this.beanFactory = beanFactory; this.scope = scope; } public final ConfigurableBeanFactory getBeanFactory() { return this.beanFactory; } @Nullable public final Scope getScope() { return this.scope; } public boolean containsObject(String key) { return (this.beanFactory.containsBean(key) || (this.scope != null && this.scope.resolveContextualObject(key) != null)); } @Nullable public Object getObject(String key) { if (this.beanFactory.containsBean(key)) { return this.beanFactory.getBean(key); } else if (this.scope != null) { return this.scope.resolveContextualObject(key); } else { return null; } } @Override public boolean equals(@Nullable Object other) { if (this == other) { return true; } if (!(other instanceof BeanExpressionContext)) { return false; } BeanExpressionContext otherContext = (BeanExpressionContext) other; return (this.beanFactory == otherContext.beanFactory && this.scope == otherContext.scope); } @Override public int hashCode() { return this.beanFactory.hashCode(); } }