Class FormHttpMessageWriter

java.lang.Object
org.springframework.http.codec.LoggingCodecSupport
org.springframework.http.codec.FormHttpMessageWriter
All Implemented Interfaces:
HttpMessageWriter<org.springframework.util.MultiValueMap<String,String>>

public class FormHttpMessageWriter extends LoggingCodecSupport implements HttpMessageWriter<org.springframework.util.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:
  • Field Details

    • DEFAULT_CHARSET

      public static final Charset DEFAULT_CHARSET
      The default charset used by the writer.
  • Constructor Details

    • FormHttpMessageWriter

      public FormHttpMessageWriter()
  • Method Details

    • 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 list of media types supported by this Writer. The list may not apply to every possible target element type and calls to this method should typically be guarded via canWrite(elementType, null). The list may also exclude media types supported only for a specific element type. Alternatively, use HttpMessageWriter.getWritableMediaTypes(ResolvableType) for a more precise list.
      Specified by:
      getWritableMediaTypes in interface HttpMessageWriter<org.springframework.util.MultiValueMap<String,String>>
      Returns:
      the general list of supported media types
    • canWrite

      public boolean canWrite(org.springframework.core.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<org.springframework.util.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(Publisher<? extends org.springframework.util.MultiValueMap<String,String>> inputStream, org.springframework.core.ResolvableType elementType, @Nullable MediaType mediaType, ReactiveHttpOutputMessage message, Map<String,Object> hints)
      Description copied from interface: HttpMessageWriter
      Write a given stream of object to the output message.
      Specified by:
      write in interface HttpMessageWriter<org.springframework.util.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(org.springframework.util.MultiValueMap<String,String> formData, Charset charset)