org.springframework.http.converter

## Class StringHttpMessageConverter

- java.lang.Object
- - org.springframework.http.converter.AbstractHttpMessageConverter<String>
  - - org.springframework.http.converter.StringHttpMessageConverter

- All Implemented Interfaces:
    HttpMessageConverter<String>

      public class StringHttpMessageConverter
      extends AbstractHttpMessageConverter<String>

  Implementation of `HttpMessageConverter` that can read and write strings.

  By default, this converter supports all media types (`*/*`), and writes with a `Content-Type` of `text/plain`. This can be overridden by setting the `supportedMediaTypes` property.

  Since:
    3.0
  Author:
    Arjen Poutsma

- - ### Field Summary

    Fields
    Modifier and Type | Field and Description
    --- | ---
    `static Charset` | `DEFAULT_CHARSET`

    - ### Fields inherited from class org.springframework.http.converter.AbstractHttpMessageConverter

      `logger`

  - ### Constructor Summary

    Constructors
    Constructor and Description
    `StringHttpMessageConverter()` A default constructor that uses `"ISO-8859-1"` as the default charset.
    `StringHttpMessageConverter(Charset defaultCharset)` A constructor accepting a default charset to use if the requested content type does not specify one.

  - ### Method Summary

    Methods
    Modifier and Type | Method and Description
    --- | ---
    `protected List<Charset>` | `getAcceptedCharsets()` Return the list of supported `Charset`.
    `protected Long` | `getContentLength(String s, MediaType contentType)` Returns the content length for the given type.
    `protected String` | `readInternal(Class<? extends String> clazz, HttpInputMessage inputMessage)` Abstract template method that reads the actual object.
    `void` | `setWriteAcceptCharset(boolean writeAcceptCharset)` Indicates whether the `Accept-Charset` should be written to any outgoing request.
    `boolean` | `supports(Class<?> clazz)` Indicates whether the given class is supported by this converter.
    `protected void` | `writeInternal(String s, HttpOutputMessage outputMessage)` Abstract template method that writes the actual body.

    - ### Methods inherited from class org.springframework.http.converter.AbstractHttpMessageConverter

      `canRead, canRead, canWrite, canWrite, getDefaultContentType, getSupportedMediaTypes, read, setSupportedMediaTypes, write`

    - ### Methods inherited from class java.lang.Object

      `clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

- - ### Field Detail

    - #### DEFAULT_CHARSET

          public static final Charset DEFAULT_CHARSET

  - ### Constructor Detail

    - #### StringHttpMessageConverter

          public StringHttpMessageConverter()

      A default constructor that uses `"ISO-8859-1"` as the default charset.
      See Also:
        `StringHttpMessageConverter(Charset)`

    - #### StringHttpMessageConverter

          public StringHttpMessageConverter(Charset defaultCharset)

      A constructor accepting a default charset to use if the requested content type does not specify one.

  - ### Method Detail

    - #### setWriteAcceptCharset

          public void setWriteAcceptCharset(boolean writeAcceptCharset)

      Indicates whether the `Accept-Charset` should be written to any outgoing request.

      Default is `true`.

    - #### supports

          public boolean supports(Class<?> clazz)

      Description copied from class: `AbstractHttpMessageConverter`
      Indicates whether the given class is supported by this converter.
      Specified by:
        `supports` in class `AbstractHttpMessageConverter<String>`
      Parameters:
        `clazz` - the class to test for support
      Returns:
        `true` if supported; `false` otherwise

    - #### readInternal

          protected String readInternal(Class<? extends String> clazz,
                            HttpInputMessage inputMessage)
                                 throws IOException

      Description copied from class: `AbstractHttpMessageConverter`
      Abstract template method that reads the actual object. Invoked from `AbstractHttpMessageConverter.read(java.lang.Class<? extends T>, org.springframework.http.HttpInputMessage)`.
      Specified by:
        `readInternal` in class `AbstractHttpMessageConverter<String>`
      Parameters:
        `clazz` - the type of object to return
        `inputMessage` - the HTTP input message to read from
      Returns:
        the converted object
      Throws:
        `IOException` - in case of I/O errors

    - #### getContentLength

          protected Long getContentLength(String s,
                              MediaType contentType)

      Description copied from class: `AbstractHttpMessageConverter`
      Returns the content length for the given type.

      By default, this returns `null`, meaning that the content length is unknown. Can be overridden in subclasses.

      Overrides:
        `getContentLength` in class `AbstractHttpMessageConverter<String>`
      Parameters:
        `s` - the type to return the content length for
      Returns:
        the content length, or `null` if not known

    - #### writeInternal

          protected void writeInternal(String s,
                           HttpOutputMessage outputMessage)
                                throws IOException

      Description copied from class: `AbstractHttpMessageConverter`
      Abstract template method that writes the actual body. Invoked from `AbstractHttpMessageConverter.write(T, org.springframework.http.MediaType, org.springframework.http.HttpOutputMessage)`.
      Specified by:
        `writeInternal` in class `AbstractHttpMessageConverter<String>`
      Parameters:
        `s` - the object to write to the output message
        `outputMessage` - the message to write to
      Throws:
        `IOException` - in case of I/O errors

    - #### getAcceptedCharsets

          protected List<Charset> getAcceptedCharsets()

      Return the list of supported `Charset`.

      By default, returns `Charset.availableCharsets()`. Can be overridden in subclasses.

      Returns:
        the list of accepted charsets