spring应用手册-IOC（XML配置实现）-(36)-context:component-scan的scope-resolver属性

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context:component-scan的scope-resolver属性

spring应用手册（第一部分）

注意这个属性scope-resolver和scoped-proxy是互斥的。

这个属性跟name-generator有点类似，它是基于接口ScopeMetadataResolver的，实现resolveScopeMetadata方法，目的是为了将@Scope(value="",proxyMode=ScopedProxyMode.NO,scopeName="")的配置解析成为一个ScopeMetadata对象,Spring这里也提供了两个实现，我们一起看下。首先是org.springframework.context.annotation.AnnotationScopeMetadataResolver中，

public ScopeMetadata resolveScopeMetadata(BeanDefinition definition) { ScopeMetadata metadata = new ScopeMetadata(); if (definition instanceof AnnotatedBeanDefinition) { AnnotatedBeanDefinition annDef = (AnnotatedBeanDefinition) definition; AnnotationAttributes attributes = AnnotationConfigUtils.attributesFor(annDef.getMetadata(), this.scopeAnnotationType); if (attributes != null) { metadata.setScopeName(attributes.getAliasedString("value", this.scopeAnnotationType, definition.getSource())); ScopedProxyMode proxyMode = attributes.getEnum("proxyMode"); if (proxyMode == null || proxyMode == ScopedProxyMode.DEFAULT) { proxyMode = this.defaultProxyMode; } metadata.setScopedProxyMode(proxyMode); } } return metadata; }

org.springframework.context.annotation.Jsr330ScopeMetadataResolver中的实现

public ScopeMetadata resolveScopeMetadata(BeanDefinition definition) { ScopeMetadata metadata = new ScopeMetadata(); metadata.setScopeName(BeanDefinition.SCOPE_PROTOTYPE); if (definition instanceof AnnotatedBeanDefinition) { AnnotatedBeanDefinition annDef = (AnnotatedBeanDefinition) definition; Set<String> annTypes = annDef.getMetadata().getAnnotationTypes(); String found = null; for (String annType : annTypes) { Set<String> metaAnns = annDef.getMetadata().getMetaAnnotationTypes(annType); if (metaAnns.contains("javax.inject.Scope")) { if (found != null) { throw new IllegalStateException("Found ambiguous scope annotations on bean class [" + definition.getBeanClassName() + "]: " + found + ", " + annType); } found = annType; String scopeName = resolveScopeName(annType); if (scopeName == null) { throw new IllegalStateException( "Unsupported scope annotation - not mapped onto Spring scope name: " + annType); } metadata.setScopeName(scopeName); } } } return metadata; }