| /* |
| * 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; |
| |
| /** |
| * Parser that uses an external program (like catdoc or pdf2txt) to extract |
| * text content from a given document. |
| */ |
| public class ExternalParser implements Parser { |
| |
| /** |
| * 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) { |
| } |
| } |
| } |
| |
| /** |
| * @deprecated This method will be removed in Apache Tika 1.0. |
| */ |
| public void parse( |
| InputStream stream, ContentHandler handler, Metadata metadata) |
| throws IOException, SAXException, TikaException { |
| parse(stream, handler, metadata, new ParseContext()); |
| } |
| |
| /** |
| * 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(); |
| } |
| |
| } |