MetadataExtractor (Spring Framework 5.2.12.RELEASE API)

All Known Implementing Classes:
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.
Since:
5.2
Author:
Rossen Stoyanchev
See Also:
MetadataExtractorRegistry

Field Summary
Fields
Modifier and Type Field Description
static String ROUTE_KEY
The key to assign to the extracted "route" of the payload.

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method	Description
`Map<String,Object>`	`extract(io.rsocket.Payload payload, MimeType metadataMimeType)`	Extract a map of values from the given `Payload` metadata.

- Field Detail
  - ROUTE_KEY
```
static final String ROUTE_KEY
```
    The key to assign to the extracted "route" of the payload.
    See Also:
    Constant Field Values
- Method Detail
  - 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.
    Parameters:
    payload - the payload whose metadata should be read
    metadataMimeType - the metadata MimeType for the connection.
    Returns:
    name values pairs extracted from the metadata
    Throws:
    DecodingException - if the metadata cannot be decoded
    IllegalArgumentException - if routing metadata cannot be decoded