MetadataExtractor (Spring Framework 5.2.12.RELEASE API)

所有已知实现类:
DefaultMetadataExtractor
```
public interface MetadataExtractor
```
Strategy to extract a map of value(s) from Payload metadata, which could be composite metadata with multiple entries. Each metadata entry is decoded based on its MimeType and a name is assigned to the decoded value. The resulting name-value pairs can be added to the headers of a Message.
从以下版本开始:
5.2
作者:
Rossen Stoyanchev
另请参阅:
MetadataExtractorRegistry

字段概要
字段
修饰符和类型字段说明
static String ROUTE_KEY
The key to assign to the extracted "route" of the payload.

方法概要

所有方法实例方法抽象方法
修饰符和类型	方法	说明
`Map<String,Object>`	`extract(io.rsocket.Payload payload, MimeType metadataMimeType)`	Extract a map of values from the given `Payload` metadata.

- 字段详细资料
  - ROUTE_KEY
```
static final String ROUTE_KEY
```
    The key to assign to the extracted "route" of the payload.
    另请参阅:
    常量字段值
- 方法详细资料
  - extract
```
Map<String,Object> extract(io.rsocket.Payload payload,
                                 MimeType metadataMimeType)
```
    Extract a map of values from the given Payload metadata. The Payload "route", if present, should be saved under ROUTE_KEY.
    参数:
    payload - the payload whose metadata should be read
    metadataMimeType - the metadata MimeType for the connection.
    返回:
    name values pairs extracted from the metadata
    抛出:
    DecodingException - if the metadata cannot be decoded
    IllegalArgumentException - if routing metadata cannot be decoded