Package org.docx4j.org.apache.poi.poifs.filesystem

Class OPOIFSFileSystem

java.lang.Object
org.docx4j.org.apache.poi.poifs.filesystem.OPOIFSFileSystem
All Implemented Interfaces:
POIFSViewable
public class OPOIFSFileSystem extends Object implements POIFSViewable

This is the main class of the POIFS system; it manages the entire life cycle of the filesystem.

This is the older version, which uses more memory, and doesn't support in-place writes.

  • Constructor Details

    • OPOIFSFileSystem

      public OPOIFSFileSystem()
      Constructor, intended for writing

    • OPOIFSFileSystem

      public OPOIFSFileSystem(InputStream stream) throws IOException
      Create a OPOIFSFileSystem from an InputStream. Normally the stream is read until EOF. The stream is always closed.

      Some streams are usable after reaching EOF (typically those that return true for markSupported()). In the unlikely case that the caller has such a stream and needs to use it after this constructor completes, a work around is to wrap the stream in order to trap the close() call. A convenience method ( createNonClosingInputStream()) has been provided for this purpose: 

       InputStream wrappedStream = OPOIFSFileSystem.createNonClosingInputStream(is);
 HSSFWorkbook wb = new HSSFWorkbook(wrappedStream);
 is.reset();
 doSomethingElse(is);
      Note also the special case of ByteArrayInputStream for which the close() method does nothing. 
       ByteArrayInputStream bais = ...
 HSSFWorkbook wb = new HSSFWorkbook(bais); // calls bais.close() !
 bais.reset(); // no problem
 doSomethingElse(bais);
      Parameters:
      stream - the InputStream from which to read the data
      Throws:
      IOException - on errors reading, or on invalid data

  • Method Details

    • createNonClosingInputStream

      public static InputStream createNonClosingInputStream(InputStream is)
      Convenience method for clients that want to avoid the auto-close behaviour of the constructor.

    • closeInputStream

      protected void closeInputStream(InputStream stream, boolean success)
      Parameters:
      stream - the stream to be closed
      success - false if an exception is currently being thrown in the calling method

    • hasPOIFSHeader

      public static boolean hasPOIFSHeader(InputStream inp) throws IOException
      Checks that the supplied InputStream (which MUST support mark and reset, or be a PushbackInputStream) has a POIFS (OLE2) header at the start of it. If your InputStream does not support mark / reset, then wrap it in a PushBackInputStream, then be sure to always use that, and not the original!
      Parameters:
      inp - An InputStream which supports either mark/reset, or is a PushbackInputStream
      Throws:
      IOException

    • hasPOIFSHeader

      public static boolean hasPOIFSHeader(byte[] header8Bytes)
      Checks if the supplied first 8 bytes of a stream / file has a POIFS (OLE2) header.

    • createDocument

      public DocumentEntry createDocument(InputStream stream, String name) throws IOException
      Create a new document to be added to the root directory
      Parameters:
      stream - the InputStream from which the document's data will be obtained
      name - the name of the new POIFSDocument
      Returns:
      the new DocumentEntry
      Throws:
      IOException - on error creating the new POIFSDocument

    • createDocument

      public DocumentEntry createDocument(String name, int size, POIFSWriterListener writer) throws IOException
      create a new DocumentEntry in the root entry; the data will be provided later
      Parameters:
      name - the name of the new DocumentEntry
      size - the size of the new DocumentEntry
      writer - the writer of the new DocumentEntry
      Returns:
      the new DocumentEntry
      Throws:
      IOException

    • createDirectory

      public DirectoryEntry createDirectory(String name) throws IOException
      create a new DirectoryEntry in the root directory
      Parameters:
      name - the name of the new DirectoryEntry
      Returns:
      the new DirectoryEntry
      Throws:
      IOException - on name duplication

    • writeFilesystem

      public void writeFilesystem(OutputStream stream) throws IOException
      Write the filesystem out
      Parameters:
      stream - the OutputStream to which the filesystem will be written
      Throws:
      IOException - thrown on errors writing to the stream

    • main

      public static void main(String[] args) throws IOException
      read in a file and write it back out again
      Parameters:
      args - names of the files; arg[ 0 ] is the input file, arg[ 1 ] is the output file
      Throws:
      IOException

    • getRoot

      public DirectoryNode getRoot()
      get the root entry
      Returns:
      the root entry

    • createDocumentInputStream

      public DocumentInputStream createDocumentInputStream(String documentName) throws IOException
      open a document in the root entry's list of entries
      Parameters:
      documentName - the name of the document to be opened
      Returns:
      a newly opened DocumentInputStream
      Throws:
      IOException - if the document does not exist or the name is that of a DirectoryEntry

    • getViewableArray

      public Object[] getViewableArray()
      Get an array of objects, some of which may implement POIFSViewable
      Specified by:
      getViewableArray in interface POIFSViewable
      Returns:
      an array of Object; may not be null, but may be empty

    • getViewableIterator

      public Iterator<Object> getViewableIterator()
      Get an Iterator of objects, some of which may implement POIFSViewable
      Specified by:
      getViewableIterator in interface POIFSViewable
      Returns:
      an Iterator; may not be null, but may have an empty back end store

    • preferArray

      public boolean preferArray()
      Give viewers a hint as to whether to call getViewableArray or getViewableIterator
      Specified by:
      preferArray in interface POIFSViewable
      Returns:
      true if a viewer should call getViewableArray, false if a viewer should call getViewableIterator

    • getShortDescription

      public String getShortDescription()
      Provides a short description of the object, to be used when a POIFSViewable object has not provided its contents.
      Specified by:
      getShortDescription in interface POIFSViewable
      Returns:
      short description

    • getBigBlockSize

      public int getBigBlockSize()
      Returns:
      The Big Block size, normally 512 bytes, sometimes 4096 bytes

    • getBigBlockSizeDetails

      public POIFSBigBlockSize getBigBlockSizeDetails()
      Returns:
      The Big Block size, normally 512 bytes, sometimes 4096 bytes