pdstream.java

非常有用的操作pdf文件的java源码

        return stream;
    }
    
    /**
     * This will get the length of the filtered/compressed stream.  This is readonly in the 
     * PD Model and will be managed by this class.
     * 
     * @return The length of the filtered stream.
     */
    public int getLength()
    {
        return stream.getInt( "Length", 0 );
    }
    
    /**
     * This will get the list of filters that are associated with this stream.  Or
     * null if there are none.
     * @return A list of all encoding filters to apply to this stream.
     */
    public List getFilters()
    {
        List retval = null;
        COSBase filters = stream.getFilters();
        if( filters instanceof COSName )
        {
            COSName name = (COSName)filters;
            retval = new COSArrayList( name.getName(), name, stream, "Filter" );
        }
        else if( filters instanceof COSArray )
        {
            retval = COSArrayList.convertCOSNameCOSArrayToList( (COSArray)filters );
        }
        return retval;
    }
    
    /**
     * This will set the filters that are part of this stream.
     * 
     * @param filters The filters that are part of this stream.
     */
    public void setFilters( List filters )
    {
        COSBase obj = COSArrayList.convertStringListToCOSNameCOSArray( filters );
        stream.setItem( "Filter", obj );
    }
    
    /**
     * Get the list of decode parameters.  Each entry in the list will refer to 
     * an entry in the filters list.
     * 
     * @return The list of decode parameters.
     * 
     * @throws IOException if there is an error retrieving the parameters.
     */
    public List getDecodeParams() throws IOException
    {
        List retval = null;
        
        COSBase dp = stream.getDictionaryObject( "DecodeParms" );
        if( dp == null )
        {
            //See PDF Ref 1.5 implementation note 7, the DP is sometimes used instead.
            dp = stream.getDictionaryObject( "DP" );
        }
        if( dp instanceof COSDictionary )
        {
            Map map = COSDictionaryMap.convertBasicTypesToMap( (COSDictionary)dp );
            retval = new COSArrayList(map, dp, stream, "DecodeParams" );
        }
        else if( dp instanceof COSArray )
        {
            COSArray array = (COSArray)dp;
            List actuals = new ArrayList();
            for( int i=0; i<array.size(); i++ )
            {
                actuals.add( 
                    COSDictionaryMap.convertBasicTypesToMap( 
                        (COSDictionary)array.getObject( i ) ) );
            }
            retval = new COSArrayList(actuals, array);
        }
        
        return retval;
    }
    
    /**
     * This will set the list of decode params.
     * 
     * @param decodeParams The list of decode params.
     */
    public void setDecodeParams( List decodeParams )
    {
        stream.setItem(
            "DecodeParams", COSArrayList.converterToCOSArray( decodeParams ) );
    }
    
    /**
     * This will get the file specification for this stream.  This is only
     * required for external files.
     * 
     * @return The file specification.
     * 
     * @throws IOException If there is an error creating the file spec.
     */
    public PDFileSpecification getFile() throws IOException
    {
        COSBase f = stream.getDictionaryObject( "F" );
        PDFileSpecification retval = PDFileSpecification.createFS( f );
        return retval;
    }
    
    /**
     * Set the file specification.
     * @param f The file specification.
     */
    public void setFile( PDFileSpecification f )
    {
        stream.setItem( "F", f );
    }
    
    /**
     * This will get the list of filters that are associated with this stream.  Or
     * null if there are none.
     * @return A list of all encoding filters to apply to this stream.
     */
    public List getFileFilters()
    {
        List retval = null;
        COSBase filters = stream.getDictionaryObject( "FFilter" );
        if( filters instanceof COSName )
        {
            COSName name = (COSName)filters;
            retval = new COSArrayList( name.getName(), name, stream, "FFilter" );
        }
        else if( filters instanceof COSArray )
        {
            retval = COSArrayList.convertCOSNameCOSArrayToList( (COSArray)filters );
        }
        return retval;
    }
    
    /**
     * This will set the filters that are part of this stream.
     * 
     * @param filters The filters that are part of this stream.
     */
    public void setFileFilters( List filters )
    {
        COSBase obj = COSArrayList.convertStringListToCOSNameCOSArray( filters );
        stream.setItem( "FFilter", obj );
    }
    
    /**
     * Get the list of decode parameters.  Each entry in the list will refer to 
     * an entry in the filters list.
     * 
     * @return The list of decode parameters.
     * 
     * @throws IOException if there is an error retrieving the parameters.
     */
    public List getFileDecodeParams() throws IOException
    {
        List retval = null;
        
        COSBase dp = stream.getDictionaryObject( "FDecodeParms" );
        if( dp instanceof COSDictionary )
        {
            Map map = COSDictionaryMap.convertBasicTypesToMap( (COSDictionary)dp );
            retval = new COSArrayList(map, dp, stream, "FDecodeParams" );
        }
        else if( dp instanceof COSArray )
        {
            COSArray array = (COSArray)dp;
            List actuals = new ArrayList();
            for( int i=0; i<array.size(); i++ )
            {
                actuals.add( 
                    COSDictionaryMap.convertBasicTypesToMap( 
                        (COSDictionary)array.getObject( i ) ) );
            }
            retval = new COSArrayList(actuals, array);
        }
        
        return retval;
    }
    
    /**
     * This will set the list of decode params.
     * 
     * @param decodeParams The list of decode params.
     */
    public void setFileDecodeParams( List decodeParams )
    {
        stream.setItem(
            "FDecodeParams", COSArrayList.converterToCOSArray( decodeParams ) );
    }
    
    /**
     * This will copy the stream into a byte array. 
     * 
     * @return The byte array of the filteredStream
     * @throws IOException When getFilteredStream did not work
     */
    public byte[] getByteArray() throws IOException
    {
        ByteArrayOutputStream output = new ByteArrayOutputStream();
        byte[] buf = new byte[1024];
        InputStream is = null;
        try
        {
            is = createInputStream();
            int amountRead = -1;
            while( (amountRead = is.read( buf )) != -1)
            {
                output.write( buf, 0, amountRead );
            }
        }
        finally
        {
            if( is != null )
            {
                is.close();
            }
        }
        return output.toByteArray();
    }
    
    /**
     * A convenience method to get this stream as a string.  Uses
     * the default system encoding. 
     * 
     * @return a String representation of this (input) stream, with the
     * platform default encoding.
     * 
     * @throws IOException if there is an error while converting the stream 
     *                     to a string.
     */
    public String getInputStreamAsString() throws IOException 
    {
        byte[] bStream = getByteArray();
        return new String(bStream);
    }
    
    /**
     * Get the metadata that is part of the document catalog.  This will 
     * return null if there is no meta data for this object.
     * 
     * @return The metadata for this object.
     */
    public PDMetadata getMetadata()
    {
        PDMetadata retval = null;
        COSStream mdStream = (COSStream)stream.getDictionaryObject( "Metadata" );
        if( mdStream != null )
        {
            retval = new PDMetadata( mdStream );
        }
        return retval;
    }
    
    /**
     * Set the metadata for this object.  This can be null.
     * 
     * @param meta The meta data for this object.
     */
    public void setMetadata( PDMetadata meta )
    {
        stream.setItem( "Metadata", meta );
    }
}