resources/TransBundle_ResourceList.java

   1 package be.nikiroo.utils.resources;
   2
   3 // code copied from from:
   4 //              http://forums.devx.com/showthread.php?t=153784,
   5 // via:
   6 //              http://stackoverflow.com/questions/3923129/get-a-list-of-resources-from-classpath-directory
   7
   8 import java.io.File;
   9 import java.io.IOException;
  10 import java.util.ArrayList;
  11 import java.util.Collection;
  12 import java.util.Enumeration;
  13 import java.util.regex.Pattern;
  14 import java.util.zip.ZipEntry;
  15 import java.util.zip.ZipException;
  16 import java.util.zip.ZipFile;
  17
  18 /**
  19  * list resources available from the classpath @ *
  20  */
  21 class TransBundle_ResourceList {
  22
  23         /**
  24          * for all elements of java.class.path get a Collection of resources Pattern
  25          * pattern = Pattern.compile(".*"); gets all resources
  26          *
  27          * @param pattern
  28          *            the pattern to match
  29          * @return the resources in the order they are found
  30          */
  31         public static Collection<String> getResources(final Pattern pattern) {
  32                 final ArrayList<String> retval = new ArrayList<String>();
  33                 final String classPath = System.getProperty("java.class.path", ".");
  34                 final String[] classPathElements = classPath.split(System
  35                                 .getProperty("path.separator"));
  36                 for (final String element : classPathElements) {
  37                         retval.addAll(getResources(element, pattern));
  38                 }
  39
  40                 return retval;
  41         }
  42
  43         private static Collection<String> getResources(final String element,
  44                         final Pattern pattern) {
  45                 final ArrayList<String> retval = new ArrayList<String>();
  46                 final File file = new File(element);
  47                 if (file.isDirectory()) {
  48                         retval.addAll(getResourcesFromDirectory(file, pattern));
  49                 } else {
  50                         retval.addAll(getResourcesFromJarFile(file, pattern));
  51                 }
  52
  53                 return retval;
  54         }
  55
  56         private static Collection<String> getResourcesFromJarFile(final File file,
  57                         final Pattern pattern) {
  58                 final ArrayList<String> retval = new ArrayList<String>();
  59                 ZipFile zf;
  60                 try {
  61                         zf = new ZipFile(file);
  62                 } catch (final ZipException e) {
  63                         throw new Error(e);
  64                 } catch (final IOException e) {
  65                         throw new Error(e);
  66                 }
  67                 final Enumeration<? extends ZipEntry> e = zf.entries();
  68                 while (e.hasMoreElements()) {
  69                         final ZipEntry ze = e.nextElement();
  70                         final String fileName = ze.getName();
  71                         final boolean accept = pattern.matcher(fileName).matches();
  72                         if (accept) {
  73                                 retval.add(fileName);
  74                         }
  75                 }
  76                 try {
  77                         zf.close();
  78                 } catch (final IOException e1) {
  79                         throw new Error(e1);
  80                 }
  81
  82                 return retval;
  83         }
  84
  85         private static Collection<String> getResourcesFromDirectory(
  86                         final File directory, final Pattern pattern) {
  87                 final ArrayList<String> retval = new ArrayList<String>();
  88                 final File[] fileList = directory.listFiles();
  89                 for (final File file : fileList) {
  90                         if (file.isDirectory()) {
  91                                 retval.addAll(getResourcesFromDirectory(file, pattern));
  92                         } else {
  93                                 try {
  94                                         final String fileName = file.getCanonicalPath();
  95                                         final boolean accept = pattern.matcher(fileName).matches();
  96                                         if (accept) {
  97                                                 retval.add(fileName);
  98                                         }
  99                                 } catch (final IOException e) {
 100                                         throw new Error(e);
 101                                 }
 102                         }
 103                 }
 104
 105                 return retval;
 106         }
 107 }