/*
* 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.tika.parser;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.Reader;
import java.util.Collections;
import java.util.HashSet;
import java.util.Set;
import org.apache.tika.exception.TikaException;
import org.apache.tika.io.IOUtils;
import org.apache.tika.io.NullOutputStream;
import org.apache.tika.metadata.Metadata;
import org.apache.tika.mime.MediaType;
import org.apache.tika.sax.XHTMLContentHandler;
import org.xml.sax.ContentHandler;
import org.xml.sax.SAXException;
/**
* Very basic parser that uses an external program (like catdoc or pdf2txt)
* to extract text content from a given document.
*
* @deprecated Use the more advanced {@link org.apache.tika.parser.external.ExternalParser} instead
*/
@Deprecated
public class ExternalParser extends AbstractParser {
/**
* Media types supported by the external program.
*/
private Set<MediaType> supportedTypes = Collections.emptySet();
/**
* The external command to invoke.
* @see Runtime#exec(String)
*/
private String command = "cat";
public Set<MediaType> getSupportedTypes(ParseContext context) {
return getSupportedTypes();
}
public Set<MediaType> getSupportedTypes() {
return supportedTypes;
}
public void setSupportedTypes(Set<MediaType> supportedTypes) {
this.supportedTypes =
Collections.unmodifiableSet(new HashSet<MediaType>(supportedTypes));
}
public String getCommand() {
return command;
}
public void setCommand(String command) {
this.command = command;
}
/**
* Executes the configured external command and passes the given document
* stream as a simple XHTML document to the given SAX content handler.
* No metadata is extracted.
*/
public void parse(
final InputStream stream, ContentHandler handler,
Metadata metadata, ParseContext context)
throws IOException, SAXException, TikaException {
XHTMLContentHandler xhtml =
new XHTMLContentHandler(handler, metadata);
Process process = Runtime.getRuntime().exec(command);
try {
sendInput(process, stream);
ignoreError(process);
extractOutput(process, xhtml);
} finally {
try {
process.waitFor();
} catch (InterruptedException ignore) {
}
}
}
/**
* Starts a thread that extracts the contents of the standard output
* stream of the given process to the given XHTML content handler.
* The standard output stream is closed once fully processed.
*
* @param process process
* @param xhtml XHTML content handler
* @throws SAXException if the XHTML SAX events could not be handled
* @throws IOException if an input error occurred
*/
private void extractOutput(Process process, XHTMLContentHandler xhtml)
throws SAXException, IOException {
Reader reader = new InputStreamReader(process.getInputStream());
try {
xhtml.startDocument();
xhtml.startElement("p");
char[] buffer = new char[1024];
for (int n = reader.read(buffer); n != -1; n = reader.read(buffer)) {
xhtml.characters(buffer, 0, n);
}
xhtml.endElement("p");
xhtml.endDocument();
} finally {
reader.close();
}
}
/**
* Starts a thread that sends the contents of the given input stream
* to the standard input stream of the given process. Potential
* exceptions are ignored, and the standard input stream is closed
* once fully processed. Note that the given input stream is <em>not</em>
* closed by this method.
*
* @param process process
* @param stream input stream
*/
private void sendInput(final Process process, final InputStream stream) {
new Thread() {
public void run() {
OutputStream stdin = process.getOutputStream();
try {
IOUtils.copy(stream, stdin);
} catch (IOException e) {
} finally {
IOUtils.closeQuietly(stdin);
}
}
}.start();
}
/**
* Starts a thread that reads and discards the contents of the
* standard error stream of the given process. Potential exceptions
* are ignored, and the error stream is closed once fully processed.
*
* @param process process
*/
private void ignoreError(final Process process) {
new Thread() {
public void run() {
InputStream error = process.getErrorStream();
try {
IOUtils.copy(error, new NullOutputStream());
} catch (IOException e) {
} finally {
IOUtils.closeQuietly(error);
}
}
}.start();
}
}