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Diffstat (limited to 'src/main/java/org/pdfbox/searchengine/lucene/LucenePDFDocument.java')
| -rw-r--r-- | src/main/java/org/pdfbox/searchengine/lucene/LucenePDFDocument.java | 387 |
1 files changed, 387 insertions, 0 deletions
diff --git a/src/main/java/org/pdfbox/searchengine/lucene/LucenePDFDocument.java b/src/main/java/org/pdfbox/searchengine/lucene/LucenePDFDocument.java new file mode 100644 index 0000000..1bb8d0c --- /dev/null +++ b/src/main/java/org/pdfbox/searchengine/lucene/LucenePDFDocument.java @@ -0,0 +1,387 @@ +/**
+ * Copyright (c) 2003, www.pdfbox.org
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ * this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ * 3. Neither the name of pdfbox; nor the names of its
+ * contributors may be used to endorse or promote products derived from this
+ * software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY
+ * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * http://www.pdfbox.org
+ *
+ */
+package org.pdfbox.searchengine.lucene;
+
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.InputStream;
+import java.io.IOException;
+import java.io.StringReader;
+import java.io.StringWriter;
+
+import java.net.URL;
+import java.net.URLConnection;
+
+import java.util.Date;
+
+import org.apache.lucene.document.DateField;
+import org.apache.lucene.document.Document;
+import org.apache.lucene.document.Field;
+
+import org.pdfbox.pdmodel.PDDocument;
+import org.pdfbox.pdmodel.PDDocumentInformation;
+
+import org.pdfbox.exceptions.CryptographyException;
+import org.pdfbox.exceptions.InvalidPasswordException;
+
+import org.pdfbox.util.PDFTextStripper;
+
+/**
+ * This class is used to create a document for the lucene search engine.
+ * This should easily plug into the IndexHTML or IndexFiles that comes with
+ * the lucene project. This class will populate the following fields.
+ * <table>
+ * <tr>
+ * <td>Lucene Field Name</td>
+ * <td>Description</td>
+ * </tr>
+ * <tr>
+ * <td>path</td>
+ * <td>File system path if loaded from a file</td>
+ * </tr>
+ * <tr>
+ * <td>url</td>
+ * <td>URL to PDF document</td>
+ * </tr>
+ * <tr>
+ * <td>contents</td>
+ * <td>Entire contents of PDF document, indexed but not stored</td>
+ * </tr>
+ * <tr>
+ * <td>summary</td>
+ * <td>First 500 characters of content</td>
+ * </tr>
+ * <tr>
+ * <td>modified</td>
+ * <td>The modified date/time according to the url or path</td>
+ * </tr>
+ * <tr>
+ * <td>uid</td>
+ * <td>A unique identifier for the Lucene document.</td>
+ * </tr>
+ * <tr>
+ * <td>CreationDate</td>
+ * <td>From PDF meta-data if available</td>
+ * </tr>
+ * <tr>
+ * <td>Creator</td>
+ * <td>From PDF meta-data if available</td>
+ * </tr>
+ * <tr>
+ * <td>Keywords</td>
+ * <td>From PDF meta-data if available</td>
+ * </tr>
+ * <tr>
+ * <td>ModificationDate</td>
+ * <td>From PDF meta-data if available</td>
+ * </tr>
+ * <tr>
+ * <td>Producer</td>
+ * <td>From PDF meta-data if available</td>
+ * </tr>
+ * <tr>
+ * <td>Subject</td>
+ * <td>From PDF meta-data if available</td>
+ * </tr>
+ * <tr>
+ * <td>Trapped</td>
+ * <td>From PDF meta-data if available</td>
+ * </tr>
+ * </table>
+ *
+ * @author Ben Litchfield
+ * @version $Revision: 1.18 $
+ */
+public final class LucenePDFDocument
+{
+ private static final char FILE_SEPARATOR = System.getProperty("file.separator").charAt(0);
+
+
+ /**
+ * private constructor because there are only static methods.
+ */
+ private LucenePDFDocument()
+ {
+ //utility class should not be instantiated
+ }
+
+ /**
+ * This will get a lucene document from a PDF file.
+ *
+ * @param is The stream to read the PDF from.
+ *
+ * @return The lucene document.
+ *
+ * @throws IOException If there is an error parsing or indexing the document.
+ */
+ public static Document getDocument( InputStream is ) throws IOException
+ {
+ Document document = new Document();
+ addContent( document, is, "<inputstream>" );
+ return document;
+ }
+
+ /**
+ * This will get a lucene document from a PDF file.
+ *
+ * @param file The file to get the document for.
+ *
+ * @return The lucene document.
+ *
+ * @throws IOException If there is an error parsing or indexing the document.
+ */
+ public static Document getDocument( File file ) throws IOException
+ {
+ Document document = new Document();
+
+ // Add the url as a field named "url". Use an UnIndexed field, so
+ // that the url is just stored with the document, but is not searchable.
+ document.add( Field.UnIndexed("path", file.getPath() ) );
+ document.add(Field.UnIndexed("url", file.getPath().replace(FILE_SEPARATOR, '/')));
+
+ // Add the last modified date of the file a field named "modified". Use a
+ // Keyword field, so that it's searchable, but so that no attempt is made
+ // to tokenize the field into words.
+ document.add(Field.Keyword("modified", DateField.timeToString( file.lastModified() )));
+
+ String uid = file.getPath().replace(FILE_SEPARATOR, '\u0000') + "\u0000" +
+ DateField.timeToString(file.lastModified() );
+
+ // Add the uid as a field, so that index can be incrementally maintained.
+ // This field is not stored with document, it is indexed, but it is not
+ // tokenized prior to indexing.
+ document.add(new Field("uid", uid, false, true, false));
+
+ FileInputStream input = null;
+ try
+ {
+ input = new FileInputStream( file );
+ addContent( document, input, file.getPath() );
+ }
+ finally
+ {
+ if( input != null )
+ {
+ input.close();
+ }
+ }
+
+
+ // return the document
+
+ return document;
+ }
+
+ /**
+ * This will get a lucene document from a PDF file.
+ *
+ * @param url The file to get the document for.
+ *
+ * @return The lucene document.
+ *
+ * @throws IOException If there is an error parsing or indexing the document.
+ */
+ public static Document getDocument( URL url ) throws IOException
+ {
+ Document document = new Document();
+ URLConnection connection = url.openConnection();
+ connection.connect();
+ // Add the url as a field named "url". Use an UnIndexed field, so
+ // that the url is just stored with the document, but is not searchable.
+ document.add( Field.UnIndexed("url", url.toExternalForm() ) );
+
+ // Add the last modified date of the file a field named "modified". Use a
+ // Keyword field, so that it's searchable, but so that no attempt is made
+ // to tokenize the field into words.
+ document.add(Field.Keyword("modified", DateField.timeToString( connection.getLastModified())));
+
+ String uid = url.toExternalForm().replace(FILE_SEPARATOR, '\u0000') + "\u0000" +
+ DateField.timeToString( connection.getLastModified() );
+
+ // Add the uid as a field, so that index can be incrementally maintained.
+ // This field is not stored with document, it is indexed, but it is not
+ // tokenized prior to indexing.
+ document.add(new Field("uid", uid, false, true, false));
+
+ InputStream input = null;
+ try
+ {
+ input = connection.getInputStream();
+ addContent( document, input,url.toExternalForm() );
+ }
+ finally
+ {
+ if( input != null )
+ {
+ input.close();
+ }
+ }
+
+ // return the document
+ return document;
+ }
+
+ /**
+ * This will add the contents to the lucene document.
+ *
+ * @param document The document to add the contents to.
+ * @param is The stream to get the contents from.
+ * @param documentLocation The location of the document, used just for debug messages.
+ *
+ * @throws IOException If there is an error parsing the document.
+ */
+ private static void addContent( Document document, InputStream is, String documentLocation ) throws IOException
+ {
+ PDDocument pdfDocument = null;
+ try
+ {
+ pdfDocument = PDDocument.load( is );
+
+
+ if( pdfDocument.isEncrypted() )
+ {
+ //Just try using the default password and move on
+ pdfDocument.decrypt( "" );
+ }
+
+ //create a writer where to append the text content.
+ StringWriter writer = new StringWriter();
+ PDFTextStripper stripper = new PDFTextStripper();
+ stripper.writeText( pdfDocument, writer );
+
+ // Note: the buffer to string operation is costless;
+ // the char array value of the writer buffer and the content string
+ // is shared as long as the buffer content is not modified, which will
+ // not occur here.
+ String contents = writer.getBuffer().toString();
+
+ StringReader reader = new StringReader( contents );
+
+ // Add the tag-stripped contents as a Reader-valued Text field so it will
+ // get tokenized and indexed.
+ document.add( Field.Text( "contents", reader ) );
+
+ PDDocumentInformation info = pdfDocument.getDocumentInformation();
+ if( info.getAuthor() != null )
+ {
+ document.add(Field.Text( "Author", info.getAuthor() ) );
+ }
+ if( info.getCreationDate() != null )
+ {
+ Date date = info.getCreationDate().getTime();
+ //for some reason lucene cannot handle dates before the epoch
+ //and throws a nasty RuntimeException, so we will check and
+ //verify that this does not happen
+ if( date.getTime() >= 0 )
+ {
+ document.add(Field.Text("CreationDate", DateField.dateToString( date ) ) );
+ }
+ }
+ if( info.getCreator() != null )
+ {
+ document.add( Field.Text( "Creator", info.getCreator() ) );
+ }
+ if( info.getKeywords() != null )
+ {
+ document.add( Field.Text( "Keywords", info.getKeywords() ) );
+ }
+ if( info.getModificationDate() != null )
+ {
+ Date date = info.getModificationDate().getTime();
+ //for some reason lucene cannot handle dates before the epoch
+ //and throws a nasty RuntimeException, so we will check and
+ //verify that this does not happen
+ if( date.getTime() >= 0 )
+ {
+ document.add(Field.Text("ModificationDate", DateField.dateToString( date ) ) );
+ }
+ }
+ if( info.getProducer() != null )
+ {
+ document.add( Field.Text( "Producer", info.getProducer() ) );
+ }
+ if( info.getSubject() != null )
+ {
+ document.add( Field.Text( "Subject", info.getSubject() ) );
+ }
+ if( info.getTitle() != null )
+ {
+ document.add( Field.Text( "Title", info.getTitle() ) );
+ }
+ if( info.getTrapped() != null )
+ {
+ document.add( Field.Text( "Trapped", info.getTrapped() ) );
+ }
+
+ int summarySize = Math.min( contents.length(), 500 );
+ String summary = contents.substring( 0, summarySize );
+ // Add the summary as an UnIndexed field, so that it is stored and returned
+ // with hit documents for display.
+ document.add( Field.UnIndexed( "summary", summary ) );
+ }
+ catch( CryptographyException e )
+ {
+ throw new IOException( "Error decrypting document(" + documentLocation + "): " + e );
+ }
+ catch( InvalidPasswordException e )
+ {
+ //they didn't suppply a password and the default of "" was wrong.
+ throw new IOException( "Error: The document(" + documentLocation +
+ ") is encrypted and will not be indexed." );
+ }
+ finally
+ {
+ if( pdfDocument != null )
+ {
+ pdfDocument.close();
+ }
+ }
+ }
+
+ /**
+ * This will test creating a document.
+ *
+ * usage: java pdfparser.searchengine.lucene.LucenePDFDocument <pdf-document>
+ *
+ * @param args command line arguments.
+ *
+ * @throws IOException If there is an error.
+ */
+ public static void main( String[] args ) throws IOException
+ {
+ if( args.length != 1 )
+ {
+ System.err.println( "usage: java org.pdfbox.searchengine.lucene.LucenePDFDocument <pdf-document>" );
+ System.exit( 1 );
+ }
+ System.out.println( "Document=" + getDocument( new File( args[0] ) ) );
+ }
+}
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