java.lang.Object
- org.springframework.http.codec.LoggingCodecSupport
- - org.springframework.http.codec.FormHttpMessageWriter

All Implemented Interfaces:
HttpMessageWriter<MultiValueMap<String,String>>
```
public class FormHttpMessageWriter
extends LoggingCodecSupport
implements HttpMessageWriter<MultiValueMap<String,String>>
```
HttpMessageWriter for writing a MultiValueMap<String, String> as HTML form data, i.e. "application/x-www-form-urlencoded", to the body of a request.
Note that unless the media type is explicitly set to MediaType.APPLICATION_FORM_URLENCODED, the canWrite(org.springframework.core.ResolvableType, org.springframework.http.MediaType) method will need generic type information to confirm the target map has String values. This is because a MultiValueMap with non-String values can be used to write multipart requests.
To support both form data and multipart requests, consider using MultipartHttpMessageWriter configured with this writer as the fallback for writing plain form data.
Since:
5.0
Author:
Sebastien Deleuze, Rossen Stoyanchev
See Also:
MultipartHttpMessageWriter

Field Summary
Fields
Modifier and Type Field Description
static Charset DEFAULT_CHARSET
The default charset used by the writer.
- Fields inherited from class org.springframework.http.codec.LoggingCodecSupport
  logger

Constructor Summary
Constructors
Constructor Description
FormHttpMessageWriter()

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`boolean`	`canWrite(ResolvableType elementType, MediaType mediaType)`	Whether the given object type is supported by this writer.
`Charset`	`getDefaultCharset()`	Return the configured default charset.
`protected MediaType`	`getMediaType(MediaType mediaType)`
`List<MediaType>`	`getWritableMediaTypes()`	Return the `MediaType`'s that this writer supports.
`protected String`	`serializeForm(MultiValueMap<String,String> formData, Charset charset)`
`void`	`setDefaultCharset(Charset charset)`	Set the default character set to use for writing form data when the response Content-Type header does not explicitly specify it.
`reactor.core.publisher.Mono<Void>`	`write(org.reactivestreams.Publisher<? extends MultiValueMap<String,String>> inputStream, ResolvableType elementType, MediaType mediaType, ReactiveHttpOutputMessage message, Map<String,Object> hints)`	Write an given stream of object to the output message.

Methods inherited from class org.springframework.http.codec.LoggingCodecSupport
isEnableLoggingRequestDetails, setEnableLoggingRequestDetails

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

Methods inherited from interface org.springframework.http.codec.HttpMessageWriter
write

- Field Detail
  - DEFAULT_CHARSET
```
public static final Charset DEFAULT_CHARSET
```
    The default charset used by the writer.
- Constructor Detail
  - FormHttpMessageWriter
```
public FormHttpMessageWriter()
```
- Method Detail
  - setDefaultCharset
```
public void setDefaultCharset(Charset charset)
```
    Set the default character set to use for writing form data when the response Content-Type header does not explicitly specify it.
    By default this is set to "UTF-8".
  - getDefaultCharset
```
public Charset getDefaultCharset()
```
    Return the configured default charset.
  - getWritableMediaTypes
```
public List<MediaType> getWritableMediaTypes()
```
    Description copied from interface: HttpMessageWriter
    Return the MediaType's that this writer supports.
    Specified by:
    getWritableMediaTypes in interface HttpMessageWriter<MultiValueMap<String,String>>
  - canWrite
```
public boolean canWrite(ResolvableType elementType,
                        @Nullable
                        MediaType mediaType)
```
    Description copied from interface: HttpMessageWriter
    Whether the given object type is supported by this writer.
    Specified by:
    canWrite in interface HttpMessageWriter<MultiValueMap<String,String>>
    Parameters:
    elementType - the type of object to check
    mediaType - the media type for the write (possibly null)
    Returns:
    true if writable, false otherwise
  - write
```
public reactor.core.publisher.Mono<Void> write(org.reactivestreams.Publisher<? extends MultiValueMap<String,String>> inputStream,
                                               ResolvableType elementType,
                                               @Nullable
                                               MediaType mediaType,
                                               ReactiveHttpOutputMessage message,
                                               Map<String,Object> hints)
```
    Description copied from interface: HttpMessageWriter
    Write an given stream of object to the output message.
    Specified by:
    write in interface HttpMessageWriter<MultiValueMap<String,String>>
    Parameters:
    inputStream - the objects to write
    elementType - the type of objects in the stream which must have been previously checked via HttpMessageWriter.canWrite(ResolvableType, MediaType)
    mediaType - the content type for the write (possibly null to indicate that the default content type of the writer must be used)
    message - the message to write to
    hints - additional information about how to encode and write
    Returns:
    indicates completion or error
  - getMediaType
```
protected MediaType getMediaType(@Nullable
                                 MediaType mediaType)
```
  - serializeForm
```
protected String serializeForm(MultiValueMap<String,String> formData,
                               Charset charset)
```

Class FormHttpMessageWriter

Field Summary

Fields inherited from class org.springframework.http.codec.LoggingCodecSupport

Constructor Summary

Method Summary

Methods inherited from class org.springframework.http.codec.LoggingCodecSupport

Methods inherited from class java.lang.Object

Methods inherited from interface org.springframework.http.codec.HttpMessageWriter

Field Detail

DEFAULT_CHARSET

Constructor Detail

FormHttpMessageWriter

Method Detail

setDefaultCharset

getDefaultCharset

getWritableMediaTypes

canWrite

write

getMediaType

serializeForm