001/*
002 * Copyright 2002-2018 the original author or authors.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *      https://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016
017package org.springframework.beans.factory.config;
018
019import org.springframework.lang.Nullable;
020import org.springframework.util.Assert;
021
022/**
023 * Context object for evaluating an expression within a bean definition.
024 *
025 * @author Juergen Hoeller
026 * @since 3.0
027 */
028public class BeanExpressionContext {
029
030        private final ConfigurableBeanFactory beanFactory;
031
032        @Nullable
033        private final Scope scope;
034
035
036        public BeanExpressionContext(ConfigurableBeanFactory beanFactory, @Nullable Scope scope) {
037                Assert.notNull(beanFactory, "BeanFactory must not be null");
038                this.beanFactory = beanFactory;
039                this.scope = scope;
040        }
041
042        public final ConfigurableBeanFactory getBeanFactory() {
043                return this.beanFactory;
044        }
045
046        @Nullable
047        public final Scope getScope() {
048                return this.scope;
049        }
050
051
052        public boolean containsObject(String key) {
053                return (this.beanFactory.containsBean(key) ||
054                                (this.scope != null && this.scope.resolveContextualObject(key) != null));
055        }
056
057        @Nullable
058        public Object getObject(String key) {
059                if (this.beanFactory.containsBean(key)) {
060                        return this.beanFactory.getBean(key);
061                }
062                else if (this.scope != null) {
063                        return this.scope.resolveContextualObject(key);
064                }
065                else {
066                        return null;
067                }
068        }
069
070
071        @Override
072        public boolean equals(@Nullable Object other) {
073                if (this == other) {
074                        return true;
075                }
076                if (!(other instanceof BeanExpressionContext)) {
077                        return false;
078                }
079                BeanExpressionContext otherContext = (BeanExpressionContext) other;
080                return (this.beanFactory == otherContext.beanFactory && this.scope == otherContext.scope);
081        }
082
083        @Override
084        public int hashCode() {
085                return this.beanFactory.hashCode();
086        }
087
088}