/*
* 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.pdfbox.pdfparser.PDFParser;
import org.pdfbox.pdmodel.PDDocument;
import org.pdfbox.util.PDFTextStripper;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.io.Reader;
import java.io.InputStream;
import java.io.IOException;
import java.io.BufferedInputStream;
import java.io.CharArrayWriter;
import java.io.CharArrayReader;
import java.io.StringReader;
/**
* Text extractor for Portable Document Format (PDF).
*/
public class PdfTextExtractor extends AbstractTextExtractor {
/**
* Logger instance.
*/
private static final Logger logger =
LoggerFactory.getLogger(PdfTextExtractor.class);
/**
* Force loading of dependent class.
*/
static {
PDFParser.class.getName();
}
/**
* Creates a new <code>PdfTextExtractor</code> instance.
*/
public PdfTextExtractor() {
super(new String[]{"application/pdf"});
}
//-------------------------------------------------------< TextExtractor >
/**
* {@inheritDoc}
*/
public Reader extractText(InputStream stream,
String type,
String encoding) throws IOException {
try {
PDFParser parser = new PDFParser(new BufferedInputStream(stream));
try {
parser.parse();
PDDocument document = parser.getPDDocument();
CharArrayWriter writer = new CharArrayWriter();
PDFTextStripper stripper = new PDFTextStripper();
stripper.setLineSeparator("\n");
stripper.writeText(document, writer);
return new CharArrayReader(writer.toCharArray());
} finally {
try {
PDDocument doc = parser.getPDDocument();
if (doc != null) {
doc.close();
}
} catch (IOException e) {
// ignore
}
}
} catch (Exception e) {
// it may happen that PDFParser throws a runtime
// exception when parsing certain pdf documents
logger.warn("Failed to extract PDF text content", e);
return new StringReader("");
} finally {
stream.close();
}
}
}