org.springframework.core.io

## Interface InputStreamSource

- All Known Subinterfaces:
    ContextResource, Resource, WritableResource
  All Known Implementing Classes:
    AbstractFileResolvingResource, AbstractResource, ByteArrayResource, ClassPathResource, DescriptiveResource, FileSystemResource, InputStreamResource, PortletContextResource, ServletContextResource, UrlResource, VfsResource

      public interface InputStreamSource

  Simple interface for objects that are sources for an `InputStream`.

  This is the base interface for Spring's more extensive `Resource` interface.

  For single-use streams, `InputStreamResource` can be used for any given `InputStream`. Spring's `ByteArrayResource` or any file-based `Resource` implementation can be used as a concrete instance, allowing one to read the underlying content stream multiple times. This makes this interface useful as an abstract content source for mail attachments, for example.

  Since:
    20.01.2004
  Author:
    Juergen Hoeller
  See Also:
    `InputStream`, `Resource`, `InputStreamResource`, `ByteArrayResource`

- - ### Method Summary

    Methods
    Modifier and Type | Method and Description
    --- | ---
    `InputStream` | `getInputStream()` Return an `InputStream`.

- - ### Method Detail

    - #### getInputStream

          InputStream getInputStream()
                                     throws IOException

      Return an `InputStream`.

      It is expected that each call creates a fresh stream.

      This requirement is particularly important when you consider an API such as JavaMail, which needs to be able to read the stream multiple times when creating mail attachments. For such a use case, it is required that each `getInputStream()` call returns a fresh stream.

      Returns:
        the input stream for the underlying resource (must not be `null`)
      Throws:
        `IOException` - if the stream could not be opened
      See Also:
        `MimeMessageHelper.addAttachment(String, InputStreamSource)`