/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.pdfbox.filter;
import java.io.IOException;
import java.util.Collection;
import java.util.HashMap;
import java.util.Map;
import org.apache.pdfbox.cos.COSName;
/**
* Factory for Filter classes.
*
* @author Ben Litchfield
*/
public final class FilterFactory
{
/**
* Singleton instance.
*/
public static final FilterFactory INSTANCE = new FilterFactory();
private final Map<COSName, Filter> filters = new HashMap<>();
private FilterFactory()
{
Filter flate = new FlateFilter();
Filter dct = new DCTFilter();
Filter ccittFax = new CCITTFaxFilter();
Filter lzw = new LZWFilter();
Filter asciiHex = new ASCIIHexFilter();
Filter ascii85 = new ASCII85Filter();
Filter runLength = new RunLengthDecodeFilter();
Filter crypt = new CryptFilter();
Filter jpx = new JPXFilter();
Filter jbig2 = new JBIG2Filter();
filters.put(COSName.FLATE_DECODE, flate);
filters.put(COSName.FLATE_DECODE_ABBREVIATION, flate);
filters.put(COSName.DCT_DECODE, dct);
filters.put(COSName.DCT_DECODE_ABBREVIATION, dct);
filters.put(COSName.CCITTFAX_DECODE, ccittFax);
filters.put(COSName.CCITTFAX_DECODE_ABBREVIATION, ccittFax);
filters.put(COSName.LZW_DECODE, lzw);
filters.put(COSName.LZW_DECODE_ABBREVIATION, lzw);
filters.put(COSName.ASCII_HEX_DECODE, asciiHex);
filters.put(COSName.ASCII_HEX_DECODE_ABBREVIATION, asciiHex);
filters.put(COSName.ASCII85_DECODE, ascii85);
filters.put(COSName.ASCII85_DECODE_ABBREVIATION, ascii85);
filters.put(COSName.RUN_LENGTH_DECODE, runLength);
filters.put(COSName.RUN_LENGTH_DECODE_ABBREVIATION, runLength);
filters.put(COSName.CRYPT, crypt);
filters.put(COSName.JPX_DECODE, jpx);
filters.put(COSName.JBIG2_DECODE, jbig2);
}
/**
* Returns a filter instance given its name as a string.
* @param filterName the name of the filter to retrieve
* @return the filter that matches the name
* @throws IOException if the filter name was invalid
*/
public Filter getFilter(String filterName) throws IOException
{
return getFilter(COSName.getPDFName(filterName));
}
/**
* Returns a filter instance given its COSName.
* @param filterName the name of the filter to retrieve
* @return the filter that matches the name
* @throws IOException if the filter name was invalid
*/
public Filter getFilter(COSName filterName) throws IOException
{
Filter filter = filters.get(filterName);
if (filter == null)
{
throw new IOException("Invalid filter: " + filterName);
}
return filter;
}
// returns all available filters, for testing
Collection<Filter> getAllFilters()
{
return filters.values();
}
}