org.eclipse.tracecompass.tmf.ui/src/org/eclipse/tracecompass/internal/tmf/ui/project/wizards/importtrace/GzipFile.java

   1 /*******************************************************************************
   2  * Copyright (c) 2015 Ericsson
   3  *
   4  * All rights reserved. This program and the accompanying materials are
   5  * made available under the terms of the Eclipse Public License v1.0 which
   6  * accompanies this distribution, and is available at
   7  * http://www.eclipse.org/legal/epl-v10.html
   8  *
   9  * Contributors:
  10  *   Marc-Andre Laperle - Initial API and implementation.
  11  *******************************************************************************/
  12
  13 package org.eclipse.tracecompass.internal.tmf.ui.project.wizards.importtrace;
  14
  15 import java.io.File;
  16 import java.io.FileInputStream;
  17 import java.io.IOException;
  18 import java.io.InputStream;
  19 import java.util.Enumeration;
  20 import java.util.zip.GZIPInputStream;
  21
  22 /**
  23  * Wrapper for a Gzipped file
  24  */
  25 public class GzipFile implements AutoCloseable {
  26
  27     private static final String GZIP_EXTENSION = ".gz"; //$NON-NLS-1$
  28
  29     private final File fFile;
  30     private final GzipEntry fEntry;
  31     private GzipEntry fCurEntry;
  32     private boolean fIsClosed = false;
  33
  34     private final InputStream fInternalEntryStream;
  35
  36     /**
  37      * Create a new GzipFile for the given file.
  38      *
  39      * @param source the source file
  40      * @throws IOException
  41      *             File not found and such
  42      */
  43     public GzipFile(File source) throws IOException {
  44         fFile = source;
  45
  46         InputStream in = new FileInputStream(source);
  47         try {
  48             // Check if it's a GZIPInputStream.
  49             fInternalEntryStream = new GZIPInputStream(in);
  50         } catch (IOException e) {
  51             in.close();
  52             throw e;
  53         }
  54         String name = source.getName();
  55         fEntry = new GzipEntry(name.substring(0, name.lastIndexOf(GZIP_EXTENSION)));
  56         fCurEntry = fEntry;
  57     }
  58
  59     /**
  60      * Close the tar file input stream.
  61      *
  62      * @throws IOException if the file cannot be successfully closed
  63      */
  64     @Override
  65     public void close() throws IOException {
  66         if (fInternalEntryStream != null && !fIsClosed) {
  67             fInternalEntryStream.close();
  68             fIsClosed = true;
  69
  70         }
  71     }
  72
  73     /**
  74      * Create a new GzipFile for the given path name.
  75      *
  76      * @param filename
  77      *            the filename of the gzip file
  78      * @throws IOException
  79      *             if the file cannot be opened
  80      */
  81     public GzipFile(String filename) throws IOException {
  82         this(new File(filename));
  83     }
  84
  85     /**
  86      * Returns an enumeration cataloguing the tar archive.
  87      *
  88      * @return enumeration of all files in the archive
  89      */
  90     public Enumeration<GzipEntry> entries() {
  91         return new Enumeration<GzipEntry>() {
  92             @Override
  93             public boolean hasMoreElements() {
  94                 return (fCurEntry != null);
  95             }
  96
  97             @Override
  98             public GzipEntry nextElement() {
  99                 GzipEntry oldEntry = fCurEntry;
 100                 fCurEntry = null;
 101                 return oldEntry;
 102             }
 103         };
 104     }
 105
 106     /**
 107      * Returns a new InputStream for the given file in the tar archive.
 108      *
 109      * @param entry
 110      *            the GzipEntry
 111      * @return an input stream for the given file
 112      */
 113     public InputStream getInputStream(GzipEntry entry) {
 114         if (entry != fEntry) {
 115             throw new IllegalArgumentException();
 116         }
 117         return fInternalEntryStream;
 118     }
 119
 120     /**
 121      * Returns the path name of the file this archive represents.
 122      *
 123      * @return path
 124      */
 125     public String getName() {
 126         return fFile.getPath();
 127     }
 128
 129     @Override
 130     protected void finalize() throws Throwable {
 131         close();
 132         super.finalize();
 133     }
 134
 135 }