src/main/java/eu/svjatoslav/meviz/htmlindexer/Utils.java

   1 /*
   2  * Meviz - Various tools collection to work with multimedia.
   3  * Copyright (C) 2012, Svjatoslav Agejenko, svjatoslav@svjatoslav.eu
   4  *
   5  * This program is free software; you can redistribute it and/or
   6  * modify it under the terms of version 2 of the GNU General Public License
   7  * as published by the Free Software Foundation.
   8  */
   9
  10 package eu.svjatoslav.meviz.htmlindexer;
  11
  12 import java.awt.image.BufferedImage;
  13 import java.io.BufferedReader;
  14 import java.io.File;
  15 import java.io.FileNotFoundException;
  16 import java.io.FileReader;
  17 import java.io.IOException;
  18 import java.util.HashSet;
  19 import java.util.zip.CRC32;
  20
  21 import javax.imageio.ImageIO;
  22
  23 import eu.svjatoslav.meviz.htmlindexer.layouts.MixedLayout;
  24
  25 public class Utils {
  26
  27         private static File lastLoadedFile;
  28
  29         private static BufferedImage lastLoadedBufferedImage;
  30
  31         /**
  32          * Load image into {@link BufferedImage} and return it. Caches last loaded
  33          * image to speed up subsequent loading attempts.
  34          *
  35          * @throws ImageFormatError
  36          * @throws IOException
  37          */
  38         public static BufferedImage getBufferedImage(final File file)
  39                         throws ImageFormatError, IOException {
  40                 if (file.equals(lastLoadedFile))
  41                         return lastLoadedBufferedImage;
  42
  43                 System.out.println("Loading image: " + file.getPath());
  44                 lastLoadedBufferedImage = ImageIO.read(file);
  45                 lastLoadedFile = file;
  46
  47                 if (lastLoadedBufferedImage == null) {
  48                         System.out.println("Error reading image: " + file);
  49                         throw new ImageFormatError("File: " + file
  50                                         + " is not a valid image.");
  51
  52                 }
  53
  54                 return lastLoadedBufferedImage;
  55         }
  56
  57         public static File getLayoutIndexFile(final Layout layout,
  58                         final File directoryToIndex) {
  59
  60                 final String indexFilePath = directoryToIndex.getAbsolutePath()
  61                                 + "/index" + layout.getFileNameSuffix() + ".html";
  62
  63                 return new File(indexFilePath);
  64         }
  65
  66         public static HashSet<Layout> getLayouts() {
  67                 final HashSet<Layout> layouts = new HashSet<Layout>();
  68                 layouts.add(new MixedLayout());
  69                 return layouts;
  70         }
  71
  72         public static String getStringCrcAsHex(final String input) {
  73
  74                 // create a new CRC-calculating object
  75                 final CRC32 crc = new CRC32();
  76
  77                 // loop, calculating CRC for each byte of the string
  78                 // There is no CRC16.update(byte[]) method.
  79                 for (final byte b : input.getBytes())
  80                         crc.update(b);
  81
  82                 // note use crc.value, not crc.getValue()
  83                 final String hex = Integer.toHexString((int) crc.getValue())
  84                                 .toUpperCase();
  85
  86                 // System.out.println("Input string: " + input);
  87                 // System.out.println("Result: " + hex);
  88
  89                 return hex;
  90         }
  91
  92         public static File getThumbnailsDirectory(final File directoryToIndex) {
  93                 return new File(getThumbnailsDirectoryPath(directoryToIndex));
  94         }
  95
  96         public static String getThumbnailsDirectoryPath(final File directoryToIndex) {
  97                 return directoryToIndex.getAbsolutePath() + "/"
  98                                 + Constants.THUMBNAILS_DIRECTORY_NAME + "/";
  99         }
 100
 101         public static boolean isMevizGeneratedIndexFile(final File indexFile)
 102                         throws FileNotFoundException, IOException {
 103
 104                 boolean isMevizFile = false;
 105
 106                 final FileReader fileReader = new FileReader(indexFile);
 107                 final BufferedReader reader = new BufferedReader(fileReader);
 108
 109                 parseFile: {
 110                         while (true) {
 111                                 final String line = reader.readLine();
 112
 113                                 if (line == null)
 114                                         break parseFile;
 115
 116                                 if (line.contains(Constants.HTML_MAGIC_STRING)) {
 117                                         isMevizFile = true;
 118                                         break parseFile;
 119                                 }
 120                         }
 121                 }
 122
 123                 reader.close();
 124                 fileReader.close();
 125                 return isMevizFile;
 126         }
 127
 128 }