java.lang.Object
- org.springframework.messaging.support.MessageHeaderAccessor
- - org.springframework.messaging.support.NativeMessageHeaderAccessor

Direct Known Subclasses:
JmsMessageHeaderAccessor, SimpMessageHeaderAccessor
```
public class NativeMessageHeaderAccessor
extends MessageHeaderAccessor
```
MessageHeaderAccessor sub-class that supports storage and access of headers from an external source such as a message broker. Headers from the external source are kept separate from other headers, in a sub-map under the key NATIVE_HEADERS. This allows separating processing headers from headers that need to be sent to or received from the external source.
This class is likely to be used through indirectly through a protocol specific sub-class that also provide factory methods to translate message headers to an from an external messaging source.
Since:
4.0
Author:
Rossen Stoyanchev

Field Summary
Fields
Modifier and Type Field Description
static String NATIVE_HEADERS
The header name used to store native headers.
- Fields inherited from class org.springframework.messaging.support.MessageHeaderAccessor
  DEFAULT_CHARSET

Constructor Summary

Constructors
Modifier	Constructor	Description
`protected`	`NativeMessageHeaderAccessor()`	Protected constructor to create a new instance.
`protected`	`NativeMessageHeaderAccessor(Map<String,List<String>> nativeHeaders)`	Protected constructor to create an instance with the given native headers.
`protected`	`NativeMessageHeaderAccessor(Message<?> message)`	Protected constructor that copies headers from another message.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`void`	`addNativeHeader(String name, String value)`	Add the specified native header value to existing values.
`void`	`addNativeHeaders(MultiValueMap<String,String> headers)`	Add the specified native headers to existing values.
`boolean`	`containsNativeHeader(String headerName)`	Whether the native header map contains the give header name.
`void`	`copyHeaders(Map<String,?> headersToCopy)`	Copy the name-value pairs from the provided Map.
`void`	`copyHeadersIfAbsent(Map<String,?> headersToCopy)`	Copy the name-value pairs from the provided Map.
`String`	`getFirstNativeHeader(String headerName)`	Return the first value for the specified native header, if present.
`static String`	`getFirstNativeHeader(String headerName, Map<String,Object> headers)`	Return the first value for the specified native header, or `null` if none.
`List<String>`	`getNativeHeader(String headerName)`	Return all values for the specified native header, if present.
`protected Map<String,List<String>>`	`getNativeHeaders()`	Subclasses can use this method to access the "native" headers sub-map.
`List<String>`	`removeNativeHeader(String headerName)`	Remove the specified native header value replacing existing values.
`void`	`setImmutable()`	By default when `MessageHeaderAccessor.getMessageHeaders()` is called, `"this"MessageHeaderAccessor` instance can no longer be used to modify the underlying message headers.
`void`	`setNativeHeader(String name, String value)`	Set the specified native header value replacing existing values.
`void`	`setNativeHeaderValues(String name, List<String> values)`	Variant of `addNativeHeader(String, String)` for all values.
`Map<String,List<String>>`	`toNativeHeaderMap()`	Return a copy of the native headers sub-map, or an empty map.

Methods inherited from class org.springframework.messaging.support.MessageHeaderAccessor
createAccessor, getAccessor, getAccessor, getAccessor, getContentType, getDetailedLogMessage, getDetailedPayloadLogMessage, getErrorChannel, getHeader, getId, getMessageHeaders, getMutableAccessor, getReplyChannel, getShortLogMessage, getShortPayloadLogMessage, getTimestamp, isModified, isMutable, isReadableContentType, isReadOnly, removeHeader, removeHeaders, setContentType, setErrorChannel, setErrorChannelName, setHeader, setHeaderIfAbsent, setLeaveMutable, setModified, setReplyChannel, setReplyChannelName, toMap, toMessageHeaders, toString, verifyType

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

- Field Detail
  - NATIVE_HEADERS
```
public static final String NATIVE_HEADERS
```
    The header name used to store native headers.
    See Also:
    Constant Field Values
- Constructor Detail
  - NativeMessageHeaderAccessor
```
protected NativeMessageHeaderAccessor()
```
    Protected constructor to create a new instance.
  - NativeMessageHeaderAccessor
```
protected NativeMessageHeaderAccessor(@Nullable
                                      Map<String,List<String>> nativeHeaders)
```
    Protected constructor to create an instance with the given native headers.
    Parameters:
    nativeHeaders - native headers to create the message with (may be null)
  - NativeMessageHeaderAccessor
```
protected NativeMessageHeaderAccessor(@Nullable
                                      Message<?> message)
```
    Protected constructor that copies headers from another message.
- Method Detail
  - getNativeHeaders
```
@Nullable
protected Map<String,List<String>> getNativeHeaders()
```
    Subclasses can use this method to access the "native" headers sub-map.
  - toNativeHeaderMap
```
public Map<String,List<String>> toNativeHeaderMap()
```
    Return a copy of the native headers sub-map, or an empty map.
  - setImmutable
```
public void setImmutable()
```
    Description copied from class: MessageHeaderAccessor
    By default when MessageHeaderAccessor.getMessageHeaders() is called, "this"MessageHeaderAccessor instance can no longer be used to modify the underlying message headers. However if MessageHeaderAccessor.setLeaveMutable(boolean) is used, this method is necessary to indicate explicitly when the MessageHeaders instance should no longer be modified.
    Overrides:
    setImmutable in class MessageHeaderAccessor
  - copyHeaders
```
public void copyHeaders(@Nullable
                        Map<String,?> headersToCopy)
```
    Description copied from class: MessageHeaderAccessor
    Copy the name-value pairs from the provided Map.
    This operation will overwrite any existing values. Use MessageHeaderAccessor.copyHeadersIfAbsent(Map) to avoid overwriting values.
    Overrides:
    copyHeaders in class MessageHeaderAccessor
  - copyHeadersIfAbsent
```
public void copyHeadersIfAbsent(@Nullable
                                Map<String,?> headersToCopy)
```
    Description copied from class: MessageHeaderAccessor
    Copy the name-value pairs from the provided Map.
    This operation will not overwrite any existing values.
    Overrides:
    copyHeadersIfAbsent in class MessageHeaderAccessor
  - containsNativeHeader
```
public boolean containsNativeHeader(String headerName)
```
    Whether the native header map contains the give header name.
    Parameters:
    headerName - the name of the header
  - getNativeHeader
```
@Nullable
public List<String> getNativeHeader(String headerName)
```
    Return all values for the specified native header, if present.
    Parameters:
    headerName - the name of the header
    Returns:
    the associated values, or null if none
  - getFirstNativeHeader
```
@Nullable
public String getFirstNativeHeader(String headerName)
```
    Return the first value for the specified native header, if present.
    Parameters:
    headerName - the name of the header
    Returns:
    the associated value, or null if none
  - setNativeHeader
```
public void setNativeHeader(String name,
                            @Nullable
                            String value)
```
    Set the specified native header value replacing existing values.
    In order for this to work, the accessor must be mutable. See MessageHeaderAccessor for details.
  - setNativeHeaderValues
```
public void setNativeHeaderValues(String name,
                                  @Nullable
                                  List<String> values)
```
    Variant of addNativeHeader(String, String) for all values.
    Since:
    5.2.12
  - addNativeHeader
```
public void addNativeHeader(String name,
                            @Nullable
                            String value)
```
    Add the specified native header value to existing values.
    In order for this to work, the accessor must be mutable. See MessageHeaderAccessor for details.
    Parameters:
    name - the name of the header
    value - the header value to set
  - addNativeHeaders
```
public void addNativeHeaders(@Nullable
                             MultiValueMap<String,String> headers)
```
    Add the specified native headers to existing values.
    Parameters:
    headers - the headers to set
  - removeNativeHeader
```
@Nullable
public List<String> removeNativeHeader(String headerName)
```
    Remove the specified native header value replacing existing values.
    In order for this to work, the accessor must be mutable. See MessageHeaderAccessor for details.
    Parameters:
    headerName - the name of the header
    Returns:
    the associated values, or null if the header was not present
  - getFirstNativeHeader
```
@Nullable
public static String getFirstNativeHeader(String headerName,
                                          Map<String,Object> headers)
```
    Return the first value for the specified native header, or null if none.
    Parameters:
    headerName - the name of the header
    headers - the headers map to introspect
    Returns:
    the associated value, or null if none

Class NativeMessageHeaderAccessor

Field Summary

Fields inherited from class org.springframework.messaging.support.MessageHeaderAccessor

Constructor Summary

Method Summary

Methods inherited from class org.springframework.messaging.support.MessageHeaderAccessor

Methods inherited from class java.lang.Object

Field Detail

NATIVE_HEADERS

Constructor Detail

NativeMessageHeaderAccessor

NativeMessageHeaderAccessor

NativeMessageHeaderAccessor

Method Detail

getNativeHeaders

toNativeHeaderMap

setImmutable

copyHeaders

copyHeadersIfAbsent

containsNativeHeader

getNativeHeader

getFirstNativeHeader

setNativeHeader

setNativeHeaderValues

addNativeHeader

addNativeHeaders

removeNativeHeader

getFirstNativeHeader