Package org.apache.commons.fileupload2.core

Interface FileItem<F extends FileItem<F>>

Type Parameters:
F - The FileItem type.
All Superinterfaces:
FileItemHeadersProvider<F>
All Known Implementing Classes:
DiskFileItem
public interface FileItem<F extends FileItem<F>> extends FileItemHeadersProvider<F>

This class represents a file or form item that was received within a multipart/form-data POST request.

After retrieving an instance of this class from a FileUpload instance (see org.apache.commons.fileupload2.core.servlet.ServletFileUpload #parseRequest(javax.servlet.http.HttpServletRequest)), you may either request all contents of the file at once using get() or request an InputStream with getInputStream() and process the file without attempting to load it into memory, which may come handy with large files.

While this interface does not extend javax.activation.DataSource (to avoid a seldom used dependency), several of the defined methods are specifically defined with the same signatures as methods in that interface. This allows an implementation of this interface to also implement javax.activation.DataSource with minimal additional work.

  • Method Summary

    Modifier and Type
    Method
    Description
    F
    delete()
    Deletes the underlying storage for a file item, including deleting any associated temporary disk file.
    byte[]
    get()
    Gets the contents of the file item as a byte array.
    String
    getContentType()
    Gets the content type passed by the browser or null if not defined.
    String
    getFieldName()
    Gets the name of the field in the multipart form corresponding to this file item.
    InputStream
    getInputStream()
    Gets an InputStream that can be used to retrieve the contents of the file.
    String
    getName()
    Gets the original file name in the client's file system, as provided by the browser (or other client software).
    OutputStream
    getOutputStream()
    Gets an OutputStream that can be used for storing the contents of the file.
    long
    getSize()
    Gets the size of the file item.
    String
    getString()
    Gets the contents of the file item as a String, using the default character encoding.
    String
    getString(Charset toCharset)
    Gets the contents of the file item as a String, using the specified encoding.
    boolean
    isFormField()
    Tests whether or not a FileItem instance represents a simple form field.
    boolean
    isInMemory()
    Tests a hint as to whether or not the file contents will be read from memory.
    F
    setFieldName(String name)
    Sets the field name used to reference this file item.
    F
    setFormField(boolean state)
    Sets whether or not a FileItem instance represents a simple form field.
    F
    write(Path file)
    Writes an uploaded item to disk.

    Methods inherited from interface org.apache.commons.fileupload2.core.FileItemHeadersProvider

    getHeaders, setHeaders

  • Method Details

    • delete

      F delete() throws IOException
      Deletes the underlying storage for a file item, including deleting any associated temporary disk file. Use this method to ensure that this is done at an earlier time, to preserve resources.
      Returns:
      this
      Throws:
      IOException - if an error occurs.

    • get

      byte[] get() throws UncheckedIOException
      Gets the contents of the file item as a byte array.
      Returns:
      The contents of the file item as a byte array.
      Throws:
      UncheckedIOException - if an I/O error occurs

    • getContentType

      String getContentType()
      Gets the content type passed by the browser or null if not defined.
      Returns:
      The content type passed by the browser or null if not defined.

    • getFieldName

      String getFieldName()
      Gets the name of the field in the multipart form corresponding to this file item.
      Returns:
      The name of the form field.

    • getInputStream

      InputStream getInputStream() throws IOException
      Gets an InputStream that can be used to retrieve the contents of the file.
      Returns:
      An InputStream that can be used to retrieve the contents of the file.
      Throws:
      IOException - if an error occurs.

    • getName

      String getName()
      Gets the original file name in the client's file system, as provided by the browser (or other client software). In most cases, this will be the base file name, without path information. However, some clients, such as the Opera browser, do include path information.
      Returns:
      The original file name in the client's file system.
      Throws:
      InvalidPathException - The file name contains a NUL character, which might be an indicator of a security attack. If you intend to use the file name anyways, catch the exception and use InvalidFileNameException#getName().

    • getOutputStream

      OutputStream getOutputStream() throws IOException
      Gets an OutputStream that can be used for storing the contents of the file.
      Returns:
      An OutputStream that can be used for storing the contents of the file.
      Throws:
      IOException - if an error occurs.

    • getSize

      long getSize()
      Gets the size of the file item.
      Returns:
      The size of the file item, in bytes.

    • getString

      String getString()
      Gets the contents of the file item as a String, using the default character encoding. This method uses get() to retrieve the contents of the item.
      Returns:
      The contents of the item, as a string.

    • getString

      String getString(Charset toCharset) throws IOException
      Gets the contents of the file item as a String, using the specified encoding. This method uses get() to retrieve the contents of the item.
      Parameters:
      toCharset - The character encoding to use.
      Returns:
      The contents of the item, as a string.
      Throws:
      IOException - if an I/O error occurs

    • isFormField

      boolean isFormField()
      Tests whether or not a FileItem instance represents a simple form field.
      Returns:
      true if the instance represents a simple form field; false if it represents an uploaded file.

    • isInMemory

      boolean isInMemory()
      Tests a hint as to whether or not the file contents will be read from memory.
      Returns:
      true if the file contents will be read from memory; false otherwise.

    • setFieldName

      F setFieldName(String name)
      Sets the field name used to reference this file item.
      Parameters:
      name - The name of the form field.
      Returns:
      this

    • setFormField

      F setFormField(boolean state)
      Sets whether or not a FileItem instance represents a simple form field.
      Parameters:
      state - true if the instance represents a simple form field; false if it represents an uploaded file.
      Returns:
      this

    • write

      F write(Path file) throws IOException
      Writes an uploaded item to disk.

      The client code is not concerned with whether or not the item is stored in memory, or on disk in a temporary location. They just want to write the uploaded item to a file.

      This method is not guaranteed to succeed if called more than once for the same item. This allows a particular implementation to use, for example, file renaming, where possible, rather than copying all of the underlying data, thus gaining a significant performance benefit.

      Parameters:
      file - The File into which the uploaded item should be stored.
      Returns:
      this
      Throws:
      IOException - if an error occurs.