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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.BeanMetadataElement; import org.springframework.beans.factory.BeanFactoryUtils; import org.springframework.lang.Nullable; import org.springframework.util.Assert; import org.springframework.util.ObjectUtils; import org.springframework.util.StringUtils; /** * Holder for a BeanDefinition with name and aliases. * Can be registered as a placeholder for an inner bean. * * <p>Can also be used for programmatic registration of inner bean * definitions. If you don't care about BeanNameAware and the like, * registering RootBeanDefinition or ChildBeanDefinition is good enough. * * @author Juergen Hoeller * @since 1.0.2 * @see org.springframework.beans.factory.BeanNameAware * @see org.springframework.beans.factory.support.RootBeanDefinition * @see org.springframework.beans.factory.support.ChildBeanDefinition */ public class BeanDefinitionHolder implements BeanMetadataElement { private final BeanDefinition beanDefinition; private final String beanName; @Nullable private final String[] aliases; /** * Create a new BeanDefinitionHolder. * @param beanDefinition the BeanDefinition to wrap * @param beanName the name of the bean, as specified for the bean definition */ public BeanDefinitionHolder(BeanDefinition beanDefinition, String beanName) { this(beanDefinition, beanName, null); } /** * Create a new BeanDefinitionHolder. * @param beanDefinition the BeanDefinition to wrap * @param beanName the name of the bean, as specified for the bean definition * @param aliases alias names for the bean, or {@code null} if none */ public BeanDefinitionHolder(BeanDefinition beanDefinition, String beanName, @Nullable String[] aliases) { Assert.notNull(beanDefinition, "BeanDefinition must not be null"); Assert.notNull(beanName, "Bean name must not be null"); this.beanDefinition = beanDefinition; this.beanName = beanName; this.aliases = aliases; } /** * Copy constructor: Create a new BeanDefinitionHolder with the * same contents as the given BeanDefinitionHolder instance. * <p>Note: The wrapped BeanDefinition reference is taken as-is; * it is {@code not} deeply copied. * @param beanDefinitionHolder the BeanDefinitionHolder to copy */ public BeanDefinitionHolder(BeanDefinitionHolder beanDefinitionHolder) { Assert.notNull(beanDefinitionHolder, "BeanDefinitionHolder must not be null"); this.beanDefinition = beanDefinitionHolder.getBeanDefinition(); this.beanName = beanDefinitionHolder.getBeanName(); this.aliases = beanDefinitionHolder.getAliases(); } /** * Return the wrapped BeanDefinition. */ public BeanDefinition getBeanDefinition() { return this.beanDefinition; } /** * Return the primary name of the bean, as specified for the bean definition. */ public String getBeanName() { return this.beanName; } /** * Return the alias names for the bean, as specified directly for the bean definition. * @return the array of alias names, or {@code null} if none */ @Nullable public String[] getAliases() { return this.aliases; } /** * Expose the bean definition's source object. * @see BeanDefinition#getSource() */ @Override @Nullable public Object getSource() { return this.beanDefinition.getSource(); } /** * Determine whether the given candidate name matches the bean name * or the aliases stored in this bean definition. */ public boolean matchesName(@Nullable String candidateName) { return (candidateName != null && (candidateName.equals(this.beanName) || candidateName.equals(BeanFactoryUtils.transformedBeanName(this.beanName)) || ObjectUtils.containsElement(this.aliases, candidateName))); } /** * Return a friendly, short description for the bean, stating name and aliases. * @see #getBeanName() * @see #getAliases() */ public String getShortDescription() { if (this.aliases == null) { return "Bean definition with name '" + this.beanName + "'"; } return "Bean definition with name '" + this.beanName + "' and aliases [" + StringUtils.arrayToCommaDelimitedString(this.aliases) + ']'; } /** * Return a long description for the bean, including name and aliases * as well as a description of the contained {@link BeanDefinition}. * @see #getShortDescription() * @see #getBeanDefinition() */ public String getLongDescription() { return getShortDescription() + ": " + this.beanDefinition; } /** * This implementation returns the long description. Can be overridden * to return the short description or any kind of custom description instead. * @see #getLongDescription() * @see #getShortDescription() */ @Override public String toString() { return getLongDescription(); } @Override public boolean equals(@Nullable Object other) { if (this == other) { return true; } if (!(other instanceof BeanDefinitionHolder)) { return false; } BeanDefinitionHolder otherHolder = (BeanDefinitionHolder) other; return this.beanDefinition.equals(otherHolder.beanDefinition) && this.beanName.equals(otherHolder.beanName) && ObjectUtils.nullSafeEquals(this.aliases, otherHolder.aliases); } @Override public int hashCode() { int hashCode = this.beanDefinition.hashCode(); hashCode = 29 * hashCode + this.beanName.hashCode(); hashCode = 29 * hashCode + ObjectUtils.nullSafeHashCode(this.aliases); return hashCode; } }