Package org.apache.commons.vfs2

Interface FileContent

All Superinterfaces:
AutoCloseable, Closeable
All Known Implementing Classes:
DefaultFileContent
public interface FileContent extends Closeable
Represents the data content of a file.

To read from a file, use the InputStream returned by getInputStream().

To write to a file, use the OutputStream returned by getOutputStream() method. This will create the file, and the parent folder, if necessary.

A file may have multiple InputStreams open at the same time.

See Also:

  • Method Details

    • close

      void close() throws FileSystemException
      Closes all resources used by the content, including any open stream. Commits pending changes to the file.

      This method is a hint to the implementation that it can release resources. This object can continue to be used after calling this method.

      Specified by:
      close in interface AutoCloseable
      Specified by:
      close in interface Closeable
      Throws:
      FileSystemException - if an error occurs closing the file.

    • getAttribute

      Object getAttribute(String attrName) throws FileSystemException
      Gets the value of an attribute of the file's content.
      Parameters:
      attrName - The name of the attribute. Attribute names are case-insensitive.
      Returns:
      The value of the attribute, or null if the attribute value is unknown.
      Throws:
      FileSystemException - If the file does not exist, or does not support attributes.

    • getAttributeNames

      String[] getAttributeNames() throws FileSystemException
      Gets the attributes of the file's content.
      Returns:
      The names of the attributes. Never returns null;
      Throws:
      FileSystemException - If the file does not exist, or does not support attributes.

    • getAttributes

      Map<String,Object> getAttributes() throws FileSystemException
      Returns a read-only map of this file's attributes.
      Returns:
      The attribute Map.
      Throws:
      FileSystemException - If the file does not exist, or does not support attributes.

    • getByteArray

      default byte[] getByteArray() throws IOException
      Returns the content of a file as a byte array.
      Returns:
      The content as a byte array.
      Throws:
      IOException - if the file content cannot be accessed.
      Since:
      2.4

    • getCertificates

      Certificate[] getCertificates() throws FileSystemException
      Gets the certificates if any used to sign this file or folder.
      Returns:
      The certificates, or an empty array if there are no certificates or the file does not support signing.
      Throws:
      FileSystemException - If the file does not exist, or is being written.

    • getContentInfo

      FileContentInfo getContentInfo() throws FileSystemException
      Gets the content info. e.g. type, encoding, ...
      Returns:
      the FileContentInfo
      Throws:
      FileSystemException - if an error occurs.

    • getFile

      FileObject getFile()
      Gets the file which this is the content of.
      Returns:
      The FileObject this is the content of.

    • getInputStream

      InputStream getInputStream() throws FileSystemException
      Gets an input stream for reading the file's content.

      There may only be a single input or output stream open for the file at any time.

      Returns:
      An input stream to read the file's content from. The input stream is buffered, so there is no need to wrap it in a BufferedInputStream.
      Throws:
      FileSystemException - If the file does not exist, or is being read, or is being written, or on error opening the stream.

    • getInputStream

      default InputStream getInputStream(int bufferSize) throws FileSystemException
      Gets an input stream for reading the file's content.

      There may only be a single input or output stream open for the file at any time.

      Parameters:
      bufferSize - The buffer size to use.
      Returns:
      An input stream to read the file's content from. The input stream is buffered, so there is no need to wrap it in a BufferedInputStream.
      Throws:
      FileSystemException - If the file does not exist, or is being read, or is being written, or on error opening the stream.
      Since:
      2.4

    • getLastModifiedTime

      long getLastModifiedTime() throws FileSystemException
      Gets the last-modified timestamp of the file.
      Returns:
      The last-modified timestamp.
      Throws:
      FileSystemException - If the file does not exist, or is being written to, or on error determining the last-modified timestamp.

    • getOutputStream

      OutputStream getOutputStream() throws FileSystemException
      Gets an output stream for writing the file's content.

      If the file does not exist, this method creates it, and the parent folder, if necessary. If the file does exist, it is replaced with whatever is written to the output stream.

      There may only be a single input or output stream open for the file at any time.

      Returns:
      An output stream to write the file's content to. The stream is buffered, so there is no need to wrap it in a BufferedOutputStream.
      Throws:
      FileSystemException - If the file is read-only, or is being read, or is being written, or on error opening the stream.

    • getOutputStream

      OutputStream getOutputStream(boolean bAppend) throws FileSystemException
      Gets an output stream for writing the file's content.

      If the file does not exist, this method creates it, and the parent folder, if necessary. If the file does exist, it is replaced with whatever is written to the output stream.

      There may only be a single input or output stream open for the file at any time.

      Parameters:
      bAppend - true if you would like to append to the file. This may not be supported by all implementations.
      Returns:
      An output stream to write the file's content to. The stream is buffered, so there is no need to wrap it in a BufferedOutputStream.
      Throws:
      FileSystemException - If the file is read-only, or is being read, or is being written, or bAppend is true and the implementation does not support it, or on error opening the stream.

    • getOutputStream

      default OutputStream getOutputStream(boolean bAppend, int bufferSize) throws FileSystemException
      Gets an output stream for writing the file's content.

      If the file does not exist, this method creates it, and the parent folder, if necessary. If the file does exist, it is replaced with whatever is written to the output stream.

      There may only be a single input or output stream open for the file at any time.

      Parameters:
      bAppend - true if you would like to append to the file. This may not be supported by all implementations.
      bufferSize - The buffer size to use.
      Returns:
      An output stream to write the file's content to. The stream is buffered, so there is no need to wrap it in a BufferedOutputStream.
      Throws:
      FileSystemException - If the file is read-only, or is being read, or is being written, or bAppend is true and the implementation does not support it, or on error opening the stream.
      Since:
      2.4

    • getOutputStream

      default OutputStream getOutputStream(int bufferSize) throws FileSystemException
      Gets an output stream for writing the file's content.

      If the file does not exist, this method creates it, and the parent folder, if necessary. If the file does exist, it is replaced with whatever is written to the output stream.

      There may only be a single input or output stream open for the file at any time.

      Parameters:
      bufferSize - The buffer size to use.
      Returns:
      An output stream to write the file's content to. The stream is buffered, so there is no need to wrap it in a BufferedOutputStream.
      Throws:
      FileSystemException - If the file is read-only, or is being read, or is being written, or bAppend is true and the implementation does not support it, or on error opening the stream.
      Since:
      2.4

    • getRandomAccessContent

      RandomAccessContent getRandomAccessContent(RandomAccessMode mode) throws FileSystemException
      Gets a stream for reading/writing the file's content.

      If the file does not exist, and you use one of the write* methods, this method creates it, and the parent folder, if necessary. If the file does exist, parts of the file are replaced with whatever is written at a given position.

      There may only be a single input or output stream open for the file at any time.

      Parameters:
      mode - The mode to use to access the file.
      Returns:
      the stream for reading and writing the file's content.
      Throws:
      FileSystemException - If the file is read-only, or is being read, or is being written, or on error opening the stream.

    • getSize

      long getSize() throws FileSystemException
      Gets the size of the file, in bytes.
      Returns:
      The size of the file, in bytes.
      Throws:
      FileSystemException - If the file does not exist, or is being written to, or on error determining the size.

    • getString

      default String getString(Charset charset) throws IOException
      Returns the content of a file as a String.
      Parameters:
      charset - The file character set, may be null.
      Returns:
      The content as a byte array.
      Throws:
      IOException - if the file content cannot be accessed.
      Since:
      2.4

    • getString

      default String getString(String charset) throws IOException
      Gets the content of a file as a String.
      Parameters:
      charset - The file character set, may be null.
      Returns:
      The content as a byte array.
      Throws:
      IOException - if the file content cannot be accessed.
      Since:
      2.4

    • hasAttribute

      boolean hasAttribute(String attrName) throws FileSystemException
      Checks if an attribute of the file's content exists.
      Parameters:
      attrName - The name of the attribute.
      Returns:
      true if the attribute exists, false otherwise.
      Throws:
      FileSystemException - If the file does not exist, or does not support attributes.

    • isEmpty

      default boolean isEmpty() throws FileSystemException
      Tests if the receiver is empty.
      Returns:
      true if the receiver is empty, false otherwise.
      Throws:
      FileSystemException - If the file does not exist, or is being written to, or on error determining the size.
      Since:
      2.5.0

    • isOpen

      boolean isOpen()
      Tests if this file has open streams.
      Returns:
      true if the file is open, false otherwise.

    • removeAttribute

      void removeAttribute(String attrName) throws FileSystemException
      Removes the value of an attribute of the file's content.
      Parameters:
      attrName - The name of the attribute.
      Throws:
      FileSystemException - If the file does not exist, or is read-only, or does not support attributes, or on error removing the attribute.

    • setAttribute

      void setAttribute(String attrName, Object value) throws FileSystemException
      Sets the value of an attribute of the file's content. Creates the file if it does not exist.
      Parameters:
      attrName - The name of the attribute.
      value - The value of the attribute.
      Throws:
      FileSystemException - If the file does not exist, or is read-only, or does not support attributes, or on error setting the attribute.

    • setLastModifiedTime

      void setLastModifiedTime(long modTime) throws FileSystemException
      Sets the last-modified timestamp of the file. Creates the file if it does not exist.
      Parameters:
      modTime - The time to set the last-modified timestamp to.
      Throws:
      FileSystemException - If the file is read-only, or is being written to, or on error setting the last-modified timestamp.

    • write

      long write(FileContent output) throws IOException
      Writes this content to another FileContent.
      Parameters:
      output - The target OutputStream.
      Returns:
      the total number of bytes written
      Throws:
      IOException - if an error occurs writing the content.
      Since:
      2.1

    • write

      long write(FileObject file) throws IOException
      Writes this content to another FileObject.
      Parameters:
      file - The target FileObject.
      Returns:
      the total number of bytes written
      Throws:
      IOException - if an error occurs writing the content.
      Since:
      2.1

    • write

      long write(OutputStream output) throws IOException
      Writes this content to an OutputStream.
      Parameters:
      output - The target OutputStream.
      Returns:
      the total number of bytes written
      Throws:
      IOException - if an error occurs writing the content.
      Since:
      2.1

    • write

      long write(OutputStream output, int bufferSize) throws IOException
      Writes this content to an OutputStream.
      Parameters:
      output - The target OutputStream.
      bufferSize - The buffer size to write data chunks.
      Returns:
      the total number of bytes written
      Throws:
      IOException - if an error occurs writing the file.
      Since:
      2.1