poifsdocument.java

Office格式转换代码

    {
        _property.setStartBlock(index);
    }

    /* **********  END  implementation of BATManaged ********** */
    /* ********** START begin implementation of POIFSViewable ********** */

    /**
     * Get an array of objects, some of which may implement
     * POIFSViewable
     *
     * @return an array of Object; may not be null, but may be empty
     */

    public Object [] getViewableArray()
    {
        Object[] results = new Object[ 1 ];
        String   result;

        try
        {
            ByteArrayOutputStream output = new ByteArrayOutputStream();
            BlockWritable[]       blocks = null;

            if (_big_store.isValid())
            {
                blocks = _big_store.getBlocks();
            }
            else if (_small_store.isValid())
            {
                blocks = _small_store.getBlocks();
            }
            if (blocks != null)
            {
                for (int k = 0; k < blocks.length; k++)
                {
                    blocks[ k ].writeBlocks(output);
                }
                byte[] data = output.toByteArray();

                if (data.length > _property.getSize())
                {
                    byte[] tmp = new byte[ _property.getSize() ];

                    System.arraycopy(data, 0, tmp, 0, tmp.length);
                    data = tmp;
                }
                output = new ByteArrayOutputStream();
                HexDump.dump(data, 0, output, 0);
                result = output.toString();
            }
            else
            {
                result = "<NO DATA>";
            }
        }
        catch (IOException e)
        {
            result = e.getMessage();
        }
        results[ 0 ] = result;
        return results;
    }

    /**
     * Get an Iterator of objects, some of which may implement
     * POIFSViewable
     *
     * @return an Iterator; may not be null, but may have an empty
     * back end store
     */

    public Iterator getViewableIterator()
    {
        return Collections.EMPTY_LIST.iterator();
    }

    /**
     * Give viewers a hint as to whether to call getViewableArray or
     * getViewableIterator
     *
     * @return true if a viewer should call getViewableArray, false if
     *         a viewer should call getViewableIterator
     */

    public boolean preferArray()
    {
        return true;
    }

    /**
     * Provides a short description of the object, to be used when a
     * POIFSViewable object has not provided its contents.
     *
     * @return short description
     */

    public String getShortDescription()
    {
        StringBuffer buffer = new StringBuffer();

        buffer.append("Document: \"").append(_property.getName())
            .append("\"");
        buffer.append(" size = ").append(getSize());
        return buffer.toString();
    }

    /* **********  END  begin implementation of POIFSViewable ********** */
    private class SmallBlockStore
    {
        private SmallDocumentBlock[] smallBlocks;
        private POIFSDocumentPath    path;
        private String               name;
        private int                  size;
        private POIFSWriterListener  writer;

        /**
         * Constructor
         *
         * @param blocks blocks to construct the store from
         */

        SmallBlockStore(final Object [] blocks)
        {
            smallBlocks = new SmallDocumentBlock[ blocks.length ];
            for (int j = 0; j < blocks.length; j++)
            {
                smallBlocks[ j ] = ( SmallDocumentBlock ) blocks[ j ];
            }
            this.path   = null;
            this.name   = null;
            this.size   = -1;
            this.writer = null;
        }

        /**
         * Constructor for a small block store that will be written
         * later
         *
         * @param path path of the document
         * @param name name of the document
         * @param size length of the document
         * @param writer the object that will eventually write the document
         */

        SmallBlockStore(final POIFSDocumentPath path, final String name,
                        final int size, final POIFSWriterListener writer)
        {
            smallBlocks = new SmallDocumentBlock[ 0 ];
            this.path   = path;
            this.name   = name;
            this.size   = size;
            this.writer = writer;
        }

        /**
         * @return true if this store is a valid source of data
         */

        boolean isValid()
        {
            return ((smallBlocks.length > 0) || (writer != null));
        }

        /**
         * @return the SmallDocumentBlocks
         */

        BlockWritable [] getBlocks()
        {
            if (isValid() && (writer != null))
            {
                ByteArrayOutputStream stream  =
                    new ByteArrayOutputStream(size);
                DocumentOutputStream  dstream =
                    new DocumentOutputStream(stream, size);

                writer.processPOIFSWriterEvent(new POIFSWriterEvent(dstream,
                        path, name, size));
                smallBlocks = SmallDocumentBlock.convert(stream.toByteArray(),
                                                         size);
            }
            return smallBlocks;
        }
    }   // end private class SmallBlockStore

    private class BigBlockStore
    {
        private DocumentBlock[]     bigBlocks;
        private POIFSDocumentPath   path;
        private String              name;
        private int                 size;
        private POIFSWriterListener writer;

        /**
         * Constructor
         *
         * @param blocks the blocks making up the store
         *
         * @exception IOException on I/O error
         */

        BigBlockStore(final Object [] blocks)
            throws IOException
        {
            bigBlocks = new DocumentBlock[ blocks.length ];
            for (int j = 0; j < blocks.length; j++)
            {
                if (blocks[ j ] instanceof DocumentBlock)
                {
                    bigBlocks[ j ] = ( DocumentBlock ) blocks[ j ];
                }
                else
                {
                    bigBlocks[ j ] =
                        new DocumentBlock(( RawDataBlock ) blocks[ j ]);
                }
            }
            this.path   = null;
            this.name   = null;
            this.size   = -1;
            this.writer = null;
        }

        /**
         * Constructor for a big block store that will be written
         * later
         *
         * @param path path of the document
         * @param name name of the document
         * @param size length of the document
         * @param writer the object that will eventually write the
         *               document
         */

        BigBlockStore(final POIFSDocumentPath path, final String name,
                      final int size, final POIFSWriterListener writer)
        {
            bigBlocks   = new DocumentBlock[ 0 ];
            this.path   = path;
            this.name   = name;
            this.size   = size;
            this.writer = writer;
        }

        /**
         * @return true if this store is a valid source of data
         */

        boolean isValid()
        {
            return ((bigBlocks.length > 0) || (writer != null));
        }

        /**
         * @return the DocumentBlocks
         */

        DocumentBlock [] getBlocks()
        {
            if (isValid() && (writer != null))
            {
                ByteArrayOutputStream stream  =
                    new ByteArrayOutputStream(size);
                DocumentOutputStream  dstream =
                    new DocumentOutputStream(stream, size);

                writer.processPOIFSWriterEvent(new POIFSWriterEvent(dstream,
                        path, name, size));
                bigBlocks = DocumentBlock.convert(stream.toByteArray(), size);
            }
            return bigBlocks;
        }

        /**
         * write the blocks to a stream
         *
         * @param stream the stream to which the data is to be written
         *
         * @exception IOException on error
         */

        void writeBlocks(OutputStream stream)
            throws IOException
        {
            if (isValid())
            {
                if (writer != null)
                {
                    DocumentOutputStream dstream =
                        new DocumentOutputStream(stream, size);

                    writer.processPOIFSWriterEvent(
                        new POIFSWriterEvent(dstream, path, name, size));
                    dstream.writeFiller(countBlocks()
                                        * POIFSConstants
                                            .BIG_BLOCK_SIZE, DocumentBlock
                                            .getFillByte());
                }
                else
                {
                    for (int k = 0; k < bigBlocks.length; k++)
                    {
                        bigBlocks[ k ].writeBlocks(stream);
                    }
                }
            }
        }

        /**
         * @return number of big blocks making up this document
         */

        int countBlocks()
        {
            int rval = 0;

            if (isValid())
            {
                if (writer != null)
                {
                    rval = (size + POIFSConstants.BIG_BLOCK_SIZE - 1)
                           / POIFSConstants.BIG_BLOCK_SIZE;
                }
                else
                {
                    rval = bigBlocks.length;
                }
            }
            return rval;
        }
    }   // end private class BigBlockStore
}       // end class POIFSDocument