Java tutorial
/** * 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 com.cloudera.knittingboar.utils; 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.OutputStream; import java.util.Iterator; import java.util.LinkedList; import java.util.List; import java.util.zip.GZIPInputStream; import org.apache.commons.compress.archivers.ArchiveException; import org.apache.commons.compress.archivers.ArchiveStreamFactory; import org.apache.commons.compress.archivers.tar.TarArchiveEntry; import org.apache.commons.compress.archivers.tar.TarArchiveInputStream; import org.apache.commons.compress.utils.IOUtils; import org.apache.mahout.math.Vector; public class Utils { public static void UnTarAndZipGZFile(final File inputFile, final File outputDir) throws FileNotFoundException, IOException, ArchiveException { unTar(inputFile, outputDir); unGzip(inputFile, outputDir); } /** * Untar an input file into an output file. * * The output file is created in the output folder, having the same name as * the input file, minus the '.tar' extension. * * @param inputFile * the input .tar file * @param outputDir * the output directory file. * @throws IOException * @throws FileNotFoundException * * @return The {@link List} of {@link File}s with the untared content. * @throws ArchiveException */ private static List<File> unTar(final File inputFile, final File outputDir) throws FileNotFoundException, IOException, ArchiveException { System.out.println( String.format("Untaring %s to dir %s.", inputFile.getAbsolutePath(), outputDir.getAbsolutePath())); final List<File> untaredFiles = new LinkedList<File>(); final InputStream is = new FileInputStream(inputFile); final TarArchiveInputStream debInputStream = (TarArchiveInputStream) new ArchiveStreamFactory() .createArchiveInputStream("tar", is); TarArchiveEntry entry = null; while ((entry = (TarArchiveEntry) debInputStream.getNextEntry()) != null) { final File outputFile = new File(outputDir, entry.getName()); if (entry.isDirectory()) { System.out.println( String.format("Attempting to write output directory %s.", outputFile.getAbsolutePath())); if (!outputFile.exists()) { System.out.println(String.format("Attempting to create output directory %s.", outputFile.getAbsolutePath())); if (!outputFile.mkdirs()) { throw new IllegalStateException( String.format("Couldn't create directory %s.", outputFile.getAbsolutePath())); } } } else { System.out.println(String.format("Creating output file %s.", outputFile.getAbsolutePath())); final OutputStream outputFileStream = new FileOutputStream(outputFile); IOUtils.copy(debInputStream, outputFileStream); outputFileStream.close(); } untaredFiles.add(outputFile); } debInputStream.close(); return untaredFiles; } /** * Ungzip an input file into an output file. * <p> * The output file is created in the output folder, having the same name as * the input file, minus the '.gz' extension. * * @param inputFile * the input .gz file * @param outputDir * the output directory file. * @throws IOException * @throws FileNotFoundException * * @return The {@File} with the ungzipped content. */ private static File unGzip(final File inputFile, final File outputDir) throws FileNotFoundException, IOException { System.out.println(String.format("Ungzipping %s to dir %s.", inputFile.getAbsolutePath(), outputDir.getAbsolutePath())); final File outputFile = new File(outputDir, inputFile.getName().substring(0, inputFile.getName().length() - 3)); final GZIPInputStream in = new GZIPInputStream(new FileInputStream(inputFile)); final FileOutputStream out = new FileOutputStream(outputFile); for (int c = in.read(); c != -1; c = in.read()) { out.write(c); } in.close(); out.close(); return outputFile; } public static void PrintVector(Vector v) { boolean first = true; Iterator<Vector.Element> nonZeros = v.iterator(); while (nonZeros.hasNext()) { Vector.Element vec_loc = nonZeros.next(); if (!first) { System.out.print(","); } else { first = false; } System.out.print(" " + vec_loc.get()); } System.out.println(""); } public static void PrintVectorSection(Vector v, int num) { boolean first = true; Iterator<Vector.Element> nonZeros = v.iterator(); int cnt = 0; while (nonZeros.hasNext()) { Vector.Element vec_loc = nonZeros.next(); if (!first) { System.out.print(","); } else { first = false; } System.out.print(" " + vec_loc.get()); if (cnt > num) { break; } cnt++; } System.out.println(" ######## "); } public static void PrintVectorNonZero(Vector v) { boolean first = true; Iterator<Vector.Element> nonZeros = v.iterateNonZero(); while (nonZeros.hasNext()) { Vector.Element vec_loc = nonZeros.next(); if (!first) { System.out.print(","); } else { first = false; } System.out.print(" " + vec_loc.get()); } System.out.println(""); } public static void PrintVectorSectionNonZero(Vector v, int size) { boolean first = true; Iterator<Vector.Element> nonZeros = v.iterateNonZero(); int cnt = 0; while (nonZeros.hasNext()) { Vector.Element vec_loc = nonZeros.next(); if (!first) { System.out.print(","); } else { first = false; } System.out.print(" " + vec_loc.get()); if (cnt > size) { break; } cnt++; } System.out.println(""); } }