Java tutorial
/* Copyright 2008-2010 Gephi Authors : Mathieu Bastian <mathieu.bastian@gephi.org> Website : http://www.gephi.org This file is part of Gephi. DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER. Copyright 2011 Gephi Consortium. All rights reserved. The contents of this file are subject to the terms of either the GNU General Public License Version 3 only ("GPL") or the Common Development and Distribution License("CDDL") (collectively, the "License"). You may not use this file except in compliance with the License. You can obtain a copy of the License at http://gephi.org/about/legal/license-notice/ or /cddl-1.0.txt and /gpl-3.0.txt. See the License for the specific language governing permissions and limitations under the License. When distributing the software, include this License Header Notice in each file and include the License files at /cddl-1.0.txt and /gpl-3.0.txt. If applicable, add the following below the License Header, with the fields enclosed by brackets [] replaced by your own identifying information: "Portions Copyrighted [year] [name of copyright owner]" If you wish your version of this file to be governed by only the CDDL or only the GPL Version 3, indicate your decision by adding "[Contributor] elects to include this software in this distribution under the [CDDL or GPL Version 3] license." If you do not indicate a single choice of license, a recipient has the option to distribute your version of this file under either the CDDL, the GPL Version 3 or to extend the choice of license to its licensees as provided above. However, if you add GPL Version 3 code and therefore, elected the GPL Version 3 license, then the option applies only if the new code is made subject to such option by the copyright holder. Contributor(s): Portions Copyrighted 2011 Gephi Consortium. */ package org.gephi.io.importer.api; import java.io.File; import java.io.FileInputStream; import java.io.FileNotFoundException; import java.io.FileOutputStream; import java.io.IOException; import java.io.InputStream; import java.io.LineNumberReader; import java.io.Reader; import java.nio.ByteBuffer; import java.util.zip.GZIPInputStream; import javax.xml.parsers.DocumentBuilder; import javax.xml.parsers.DocumentBuilderFactory; import javax.xml.parsers.ParserConfigurationException; import javax.xml.stream.Location; import javax.xml.stream.XMLInputFactory; import javax.xml.stream.XMLReporter; import javax.xml.stream.XMLStreamException; import javax.xml.stream.XMLStreamReader; import org.apache.commons.compress.compressors.bzip2.BZip2CompressorInputStream; import org.gephi.utils.CharsetToolkit; import org.openide.filesystems.FileObject; import org.openide.filesystems.FileUtil; import org.openide.util.Exceptions; import org.openide.util.NbBundle; import org.w3c.dom.Document; import org.xml.sax.InputSource; import org.xml.sax.SAXException; /** * * @author Mathieu Bastian */ public final class ImportUtils { /** * Returns a <code>LineNumberReader</code> for <code>fileObject</code>. The file must * be a text file. The charset is detected automatically. * @param fileObject the file object that is to be read * @return a reader for the text file * @throws IOException if the file can't be found or read */ public static LineNumberReader getTextReader(FileObject fileObject) throws IOException { try { return getTextReader(fileObject.getInputStream()); } catch (IOException ex) { throw new IOException(NbBundle.getMessage(ImportUtils.class, "ImportUtils.error_file_not_found")); } } /** * Returns a <code>LineNumberReader</code> for <code>inputStream</code>. The stream must * be a character stream. The charset is detected automatically. * @param stream the stream that is to be read * @return a reader for the character stream * @throws IOException if the stream can't be read */ public static LineNumberReader getTextReader(InputStream stream) throws IOException { LineNumberReader reader; CharsetToolkit charsetToolkit = new CharsetToolkit(stream); reader = (LineNumberReader) charsetToolkit.getReader(); return reader; } public static LineNumberReader getTextReader(Reader reader) { LineNumberReader lineNumberReader = new LineNumberReader(reader); return lineNumberReader; } public static Document getXMLDocument(InputStream stream) throws RuntimeException { try { DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance(); DocumentBuilder builder = factory.newDocumentBuilder(); Document document = builder.parse(stream); return document; } catch (ParserConfigurationException ex) { throw new RuntimeException( NbBundle.getMessage(ImportUtils.class, "ImportUtils.error_missing_document_instance_factory")); } catch (FileNotFoundException ex) { throw new RuntimeException(NbBundle.getMessage(ImportUtils.class, "ImportUtils.error_file_not_found")); } catch (SAXException ex) { throw new RuntimeException(NbBundle.getMessage(ImportUtils.class, "ImportUtils.error_sax")); } catch (IOException ex) { throw new RuntimeException(NbBundle.getMessage(ImportUtils.class, "ImportUtils.error_io")); } } public static Document getXMLDocument(Reader reader) throws RuntimeException { try { DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance(); DocumentBuilder builder = factory.newDocumentBuilder(); Document document = builder.parse(new InputSource(reader)); return document; } catch (ParserConfigurationException ex) { throw new RuntimeException( NbBundle.getMessage(ImportUtils.class, "ImportUtils.error_missing_document_instance_factory")); } catch (FileNotFoundException ex) { throw new RuntimeException(NbBundle.getMessage(ImportUtils.class, "ImportUtils.error_file_not_found")); } catch (SAXException ex) { throw new RuntimeException(NbBundle.getMessage(ImportUtils.class, "ImportUtils.error_sax")); } catch (IOException ex) { throw new RuntimeException(NbBundle.getMessage(ImportUtils.class, "ImportUtils.error_io")); } } public static Document getXMLDocument(FileObject fileObject) throws RuntimeException { try { InputStream stream = fileObject.getInputStream(); return getXMLDocument(stream); } catch (FileNotFoundException ex) { throw new RuntimeException(NbBundle.getMessage(ImportUtils.class, "ImportUtils.error_file_not_found")); } } public static XMLStreamReader getXMLReader(Reader reader) { try { XMLInputFactory inputFactory = XMLInputFactory.newInstance(); if (inputFactory.isPropertySupported("javax.xml.stream.isValidating")) { inputFactory.setProperty("javax.xml.stream.isValidating", Boolean.FALSE); } inputFactory.setXMLReporter(new XMLReporter() { @Override public void report(String message, String errorType, Object relatedInformation, Location location) throws XMLStreamException { throw new RuntimeException("Error:" + errorType + ", message : " + message); //System.out.println("Error:" + errorType + ", message : " + message); } }); return inputFactory.createXMLStreamReader(reader); } catch (XMLStreamException ex) { throw new RuntimeException(NbBundle.getMessage(ImportUtils.class, "ImportUtils.error_io")); } } public static FileObject getArchivedFile(FileObject fileObject) { if (FileUtil.isArchiveFile(fileObject)) { fileObject = FileUtil.getArchiveRoot(fileObject).getChildren()[0]; } return fileObject; } /** * Uncompress a Bzip2 file. */ public static File getBzipFile(FileObject in, File out, boolean isTar) throws IOException { // Stream buffer final int BUFF_SIZE = 8192; final byte[] buffer = new byte[BUFF_SIZE]; BZip2CompressorInputStream inputStream = null; FileOutputStream outStream = null; try { FileInputStream is = new FileInputStream(in.getPath()); inputStream = new BZip2CompressorInputStream(is); outStream = new FileOutputStream(out.getAbsolutePath()); if (isTar) { // Read Tar header int remainingBytes = readTarHeader(inputStream); // Read content ByteBuffer bb = ByteBuffer.allocateDirect(4 * BUFF_SIZE); byte[] tmpCache = new byte[BUFF_SIZE]; int nRead, nGet; while ((nRead = inputStream.read(tmpCache)) != -1) { if (nRead == 0) { continue; } bb.put(tmpCache); bb.position(0); bb.limit(nRead); while (bb.hasRemaining() && remainingBytes > 0) { nGet = Math.min(bb.remaining(), BUFF_SIZE); nGet = Math.min(nGet, remainingBytes); bb.get(buffer, 0, nGet); outStream.write(buffer, 0, nGet); remainingBytes -= nGet; } bb.clear(); } } else { int len; while ((len = inputStream.read(buffer)) > 0) { outStream.write(buffer, 0, len); } } } catch (IOException ex) { Exceptions.printStackTrace(ex); } finally { if (inputStream != null) { inputStream.close(); } if (outStream != null) { outStream.close(); } } return out; } /** * Uncompress a GZIP file. */ public static File getGzFile(FileObject in, File out, boolean isTar) throws IOException { // Stream buffer final int BUFF_SIZE = 8192; final byte[] buffer = new byte[BUFF_SIZE]; GZIPInputStream inputStream = null; FileOutputStream outStream = null; try { inputStream = new GZIPInputStream(new FileInputStream(in.getPath())); outStream = new FileOutputStream(out); if (isTar) { // Read Tar header int remainingBytes = readTarHeader(inputStream); // Read content ByteBuffer bb = ByteBuffer.allocateDirect(4 * BUFF_SIZE); byte[] tmpCache = new byte[BUFF_SIZE]; int nRead, nGet; while ((nRead = inputStream.read(tmpCache)) != -1) { if (nRead == 0) { continue; } bb.put(tmpCache); bb.position(0); bb.limit(nRead); while (bb.hasRemaining() && remainingBytes > 0) { nGet = Math.min(bb.remaining(), BUFF_SIZE); nGet = Math.min(nGet, remainingBytes); bb.get(buffer, 0, nGet); outStream.write(buffer, 0, nGet); remainingBytes -= nGet; } bb.clear(); } } else { int len; while ((len = inputStream.read(buffer)) > 0) { outStream.write(buffer, 0, len); } } } catch (IOException ex) { Exceptions.printStackTrace(ex); } finally { if (inputStream != null) { inputStream.close(); } if (outStream != null) { outStream.close(); } } return out; } private static int readTarHeader(InputStream inputStream) throws IOException { // Tar bytes final int FILE_SIZE_OFFSET = 124; final int FILE_SIZE_LENGTH = 12; final int HEADER_LENGTH = 512; ignoreBytes(inputStream, FILE_SIZE_OFFSET); String fileSizeLengthOctalString = readString(inputStream, FILE_SIZE_LENGTH).trim(); final int fileSize = Integer.parseInt(fileSizeLengthOctalString, 8); ignoreBytes(inputStream, HEADER_LENGTH - (FILE_SIZE_OFFSET + FILE_SIZE_LENGTH)); return fileSize; } private static void ignoreBytes(InputStream inputStream, int numberOfBytes) throws IOException { for (int counter = 0; counter < numberOfBytes; counter++) { inputStream.read(); } } private static String readString(InputStream inputStream, int numberOfBytes) throws IOException { return new String(readBytes(inputStream, numberOfBytes)); } private static byte[] readBytes(InputStream inputStream, int numberOfBytes) throws IOException { byte[] readBytes = new byte[numberOfBytes]; inputStream.read(readBytes); return readBytes; } }