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.io.UnsupportedEncodingException;
  19 import java.net.URLEncoder;
  20 import java.util.HashSet;
  21 import java.util.zip.CRC32;
  22
  23 import javax.imageio.ImageIO;
  24
  25 import eu.svjatoslav.meviz.htmlindexer.layouts.MixedLayout;
  26
  27 public class Utils {
  28
  29         private static File lastLoadedFile;
  30         private static final String UTF_8 = "UTF-8";
  31
  32         private static BufferedImage lastLoadedBufferedImage;
  33
  34         /**
  35          * Load image into {@link BufferedImage} and return it. Caches last loaded
  36          * image to speed up subsequent loading attempts.
  37          *
  38          * @throws ImageFormatError
  39          * @throws IOException
  40          */
  41         public static BufferedImage getBufferedImage(final File file)
  42                         throws ImageFormatError, IOException {
  43                 if (file.equals(lastLoadedFile))
  44                         return lastLoadedBufferedImage;
  45
  46                 System.out.println("Loading image: " + file.getPath());
  47                 lastLoadedBufferedImage = ImageIO.read(file);
  48                 lastLoadedFile = file;
  49
  50                 if (lastLoadedBufferedImage == null) {
  51                         System.out.println("Error reading image: " + file);
  52                         throw new ImageFormatError("File: " + file
  53                                         + " is not a valid image.");
  54
  55                 }
  56
  57                 return lastLoadedBufferedImage;
  58         }
  59
  60         public static File getLayoutIndexFile(final Layout layout,
  61                         final File directoryToIndex) {
  62
  63                 final String indexFilePath = directoryToIndex.getAbsolutePath()
  64                                 + "/index" + layout.getFileNameSuffix() + ".html";
  65
  66                 return new File(indexFilePath);
  67         }
  68
  69         public static HashSet<Layout> getLayouts() {
  70                 final HashSet<Layout> layouts = new HashSet<Layout>();
  71                 layouts.add(new MixedLayout());
  72                 return layouts;
  73         }
  74
  75         public static String getStringCrcAsHex(final String input) {
  76
  77                 // create a new CRC-calculating object
  78                 final CRC32 crc = new CRC32();
  79
  80                 // loop, calculating CRC for each byte of the string
  81                 // There is no CRC16.update(byte[]) method.
  82                 for (final byte b : input.getBytes())
  83                         crc.update(b);
  84
  85                 // note use crc.value, not crc.getValue()
  86                 final String hex = Integer.toHexString((int) crc.getValue())
  87                                 .toUpperCase();
  88
  89                 // System.out.println("Input string: " + input);
  90                 // System.out.println("Result: " + hex);
  91
  92                 return hex;
  93         }
  94
  95         public static File getThumbnailsDirectory(final File directoryToIndex) {
  96                 return new File(getThumbnailsDirectoryPath(directoryToIndex));
  97         }
  98
  99         public static String getThumbnailsDirectoryPath(final File directoryToIndex) {
 100                 return directoryToIndex.getAbsolutePath() + "/"
 101                                 + Constants.THUMBNAILS_DIRECTORY_NAME + "/";
 102         }
 103
 104         public static boolean isMevizGeneratedIndexFile(final File indexFile)
 105                         throws FileNotFoundException, IOException {
 106
 107                 boolean isMevizFile = false;
 108
 109                 final FileReader fileReader = new FileReader(indexFile);
 110                 final BufferedReader reader = new BufferedReader(fileReader);
 111
 112                 parseFile: {
 113                         while (true) {
 114                                 final String line = reader.readLine();
 115
 116                                 if (line == null)
 117                                         break parseFile;
 118
 119                                 if (line.contains(Constants.HTML_MAGIC_STRING)) {
 120                                         isMevizFile = true;
 121                                         break parseFile;
 122                                 }
 123                         }
 124                 }
 125
 126                 reader.close();
 127                 fileReader.close();
 128                 return isMevizFile;
 129         }
 130
 131         public static String urlEncode(String string) {
 132                 try {
 133                         return URLEncoder.encode(string, UTF_8);
 134                 } catch (UnsupportedEncodingException e) {
 135                         throw new RuntimeException(e);
 136                 }
 137         }
 138
 139 }