org.springframework.beans.factory.xml

## 类 DefaultBeanDefinitionDocumentReader

- java.lang.Object
- - org.springframework.beans.factory.xml.DefaultBeanDefinitionDocumentReader

- 所有已实现的接口:
    BeanDefinitionDocumentReader

      public class DefaultBeanDefinitionDocumentReader
      extends Object
      implements BeanDefinitionDocumentReader

  Default implementation of the `BeanDefinitionDocumentReader` interface that reads bean definitions according to the "spring-beans" DTD and XSD format (Spring's default XML bean definition format).

  The structure, elements, and attribute names of the required XML document are hard-coded in this class. (Of course a transform could be run if necessary to produce this format). `<beans>` does not need to be the root element of the XML document: this class will parse all bean definition elements in the XML file, regardless of the actual root element.

  从以下版本开始:
    18.12.2003
  作者:
    Rod Johnson, Juergen Hoeller, Rob Harrop, Erik Wiersma

- - ### 字段概要

    字段
    限定符和类型 | 字段和说明
    --- | ---
    `static String` | `ALIAS_ATTRIBUTE`
    `static String` | `ALIAS_ELEMENT`
    `static String` | `BEAN_ELEMENT`
    `static String` | `IMPORT_ELEMENT`
    `protected Log` | `logger`
    `static String` | `NAME_ATTRIBUTE`
    `static String` | `NESTED_BEANS_ELEMENT`
    `static String` | `PROFILE_ATTRIBUTE`
    `static String` | `RESOURCE_ATTRIBUTE`

  - ### 构造器概要

    构造器
    构造器和说明
    `DefaultBeanDefinitionDocumentReader()`

  - ### 方法概要

    所有方法 实例方法 具体方法
    限定符和类型 | 方法和说明
    --- | ---
    `protected BeanDefinitionParserDelegate` | `createDelegate(XmlReaderContext readerContext, Element root, BeanDefinitionParserDelegate parentDelegate)`
    `protected void` | `doRegisterBeanDefinitions(Element root)` Register each bean definition within the given root `<beans/>` element.
    `protected Object` | `extractSource(Element ele)` Invoke the `SourceExtractor` to pull the source metadata from the supplied `Element`.
    `protected XmlReaderContext` | `getReaderContext()` Return the descriptor for the XML resource that this parser works on.
    `protected void` | `importBeanDefinitionResource(Element ele)` Parse an "import" element and load the bean definitions from the given resource into the bean factory.
    `protected void` | `parseBeanDefinitions(Element root, BeanDefinitionParserDelegate delegate)` Parse the elements at the root level in the document: "import", "alias", "bean".
    `protected void` | `postProcessXml(Element root)` Allow the XML to be extensible by processing any custom element types last, after we finished processing the bean definitions.
    `protected void` | `preProcessXml(Element root)` Allow the XML to be extensible by processing any custom element types first, before we start to process the bean definitions.
    `protected void` | `processAliasRegistration(Element ele)` Process the given alias element, registering the alias with the registry.
    `protected void` | `processBeanDefinition(Element ele, BeanDefinitionParserDelegate delegate)` Process the given bean element, parsing the bean definition and registering it with the registry.
    `void` | `registerBeanDefinitions(Document doc, XmlReaderContext readerContext)` This implementation parses bean definitions according to the "spring-beans" XSD (or DTD, historically).

    - ### 从类继承的方法 java.lang.Object

      `clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

- - ### 字段详细资料

    - #### BEAN_ELEMENT

          public static final String BEAN_ELEMENT

      另请参阅:
        常量字段值

    - #### NESTED_BEANS_ELEMENT

          public static final String NESTED_BEANS_ELEMENT

      另请参阅:
        常量字段值

    - #### ALIAS_ELEMENT

          public static final String ALIAS_ELEMENT

      另请参阅:
        常量字段值

    - #### NAME_ATTRIBUTE

          public static final String NAME_ATTRIBUTE

      另请参阅:
        常量字段值

    - #### ALIAS_ATTRIBUTE

          public static final String ALIAS_ATTRIBUTE

      另请参阅:
        常量字段值

    - #### IMPORT_ELEMENT

          public static final String IMPORT_ELEMENT

      另请参阅:
        常量字段值

    - #### RESOURCE_ATTRIBUTE

          public static final String RESOURCE_ATTRIBUTE

      另请参阅:
        常量字段值

    - #### PROFILE_ATTRIBUTE

          public static final String PROFILE_ATTRIBUTE

      另请参阅:
        常量字段值

    - #### logger

          protected final Log logger

  - ### 构造器详细资料

    - #### DefaultBeanDefinitionDocumentReader

          public DefaultBeanDefinitionDocumentReader()

  - ### 方法详细资料

    - #### registerBeanDefinitions

          public void registerBeanDefinitions(Document doc,
                                              XmlReaderContext readerContext)

      This implementation parses bean definitions according to the "spring-beans" XSD (or DTD, historically).

      Opens a DOM Document; then initializes the default settings specified at the `<beans/>` level; then parses the contained bean definitions.

      指定者:
        `registerBeanDefinitions` 在接口中 `BeanDefinitionDocumentReader`
      参数:
        `doc` - the DOM document
        `readerContext` - the current context of the reader (includes the target registry and the resource being parsed)

    - #### getReaderContext

          protected final XmlReaderContext getReaderContext()

      Return the descriptor for the XML resource that this parser works on.

    - #### extractSource

          @Nullable
          protected Object extractSource(Element ele)

      Invoke the `SourceExtractor` to pull the source metadata from the supplied `Element`.

    - #### doRegisterBeanDefinitions

          protected void doRegisterBeanDefinitions(Element root)

      Register each bean definition within the given root `<beans/>` element.

    - #### createDelegate

          protected BeanDefinitionParserDelegate createDelegate(XmlReaderContext readerContext,
                                                                Element root,
                                                                @Nullable
                                                                BeanDefinitionParserDelegate parentDelegate)

    - #### parseBeanDefinitions

          protected void parseBeanDefinitions(Element root,
                                              BeanDefinitionParserDelegate delegate)

      Parse the elements at the root level in the document: "import", "alias", "bean".
      参数:
        `root` - the DOM root element of the document

    - #### importBeanDefinitionResource

          protected void importBeanDefinitionResource(Element ele)

      Parse an "import" element and load the bean definitions from the given resource into the bean factory.

    - #### processAliasRegistration

          protected void processAliasRegistration(Element ele)

      Process the given alias element, registering the alias with the registry.

    - #### processBeanDefinition

          protected void processBeanDefinition(Element ele,
                                               BeanDefinitionParserDelegate delegate)

      Process the given bean element, parsing the bean definition and registering it with the registry.

    - #### preProcessXml

          protected void preProcessXml(Element root)

      Allow the XML to be extensible by processing any custom element types first, before we start to process the bean definitions. This method is a natural extension point for any other custom pre-processing of the XML.

      The default implementation is empty. Subclasses can override this method to convert custom elements into standard Spring bean definitions, for example. Implementors have access to the parser's bean definition reader and the underlying XML resource, through the corresponding accessors.

      另请参阅:
        `getReaderContext()`

    - #### postProcessXml

          protected void postProcessXml(Element root)

      Allow the XML to be extensible by processing any custom element types last, after we finished processing the bean definitions. This method is a natural extension point for any other custom post-processing of the XML.

      The default implementation is empty. Subclasses can override this method to convert custom elements into standard Spring bean definitions, for example. Implementors have access to the parser's bean definition reader and the underlying XML resource, through the corresponding accessors.

      另请参阅:
        `getReaderContext()`