/*
* 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.jackrabbit.extractor;
import org.apache.poi.poifs.eventfilesystem.POIFSReader;
import org.apache.poi.poifs.eventfilesystem.POIFSReaderListener;
import org.apache.poi.poifs.eventfilesystem.POIFSReaderEvent;
import org.apache.poi.poifs.filesystem.DocumentInputStream;
import org.apache.poi.util.LittleEndian;
import java.io.Reader;
import java.io.InputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.io.ByteArrayOutputStream;
import java.io.InputStreamReader;
import java.io.ByteArrayInputStream;
/**
* Text extractor for Microsoft PowerPoint presentations.
*/
public class MsPowerPointTextExtractor extends AbstractTextExtractor {
/**
* Force loading of dependent class.
*/
static {
POIFSReader.class.getName();
}
/**
* Creates a new <code>MsPowerPointTextExtractor</code> instance.
*/
public MsPowerPointTextExtractor() {
super(new String[]{"application/vnd.ms-powerpoint",
"application/mspowerpoint"});
}
//-------------------------------------------------------< TextExtractor >
/**
* {@inheritDoc}
*/
public Reader extractText(InputStream stream,
String type,
String encoding) throws IOException {
try {
ByteArrayOutputStream baos = new ByteArrayOutputStream();
MsPowerPointListener listener = new MsPowerPointListener(baos);
POIFSReader reader = new POIFSReader();
reader.registerListener(listener);
reader.read(stream);
return new InputStreamReader(
new ByteArrayInputStream(baos.toByteArray()));
} finally {
stream.close();
}
}
//------------------------------------------------< MsPowerPointListener >
/**
* Reader listener.
*/
private class MsPowerPointListener implements POIFSReaderListener {
private OutputStream os;
MsPowerPointListener(OutputStream os) {
this.os = os;
}
public void processPOIFSReaderEvent(POIFSReaderEvent event) {
try {
if (!event.getName().equalsIgnoreCase("PowerPoint Document")) {
return;
}
DocumentInputStream input = event.getStream();
byte[] buffer = new byte[input.available()];
input.read(buffer, 0, input.available());
for (int i = 0; i < buffer.length - 20; i++) {
long type = LittleEndian.getUShort(buffer, i + 2);
long size = LittleEndian.getUInt(buffer, i + 4);
if (type == 4008) {
os.write(buffer, i + 4 + 1, (int) size + 3);
i = i + 4 + 1 + (int) size - 1;
}
}
} catch (Exception e) {
}
}
}
}