/**
* Loads specified JAR.
*
* @param jarFileInfo
* @throws IOException
*/
private void loadJar(JarFileInfo jarFileInfo) throws IOException {
lstJarFile.add(jarFileInfo);
try {
Enumeration<JarEntry> en = jarFileInfo.jarFile.entries();
final String EXT_JAR = ".jar";
while (en.hasMoreElements()) {
JarEntry je = en.nextElement();
if (je.isDirectory()) {
continue;
}
String s = je.getName().toLowerCase(); // JarEntry name
if (s.lastIndexOf(EXT_JAR) == s.length() - EXT_JAR.length()) {
JarEntryInfo inf = new JarEntryInfo(jarFileInfo, je);
File fileTemp = createTempFile(inf);
logInfo(
LogArea.JAR,
"Loading inner JAR %s from temp file %s",
inf.jarEntry,
getFilename4Log(fileTemp));
loadJar(new JarFileInfo(new JarFile(fileTemp), inf.getName(), jarFileInfo, fileTemp));
}
}
} catch (JarClassLoaderException e) {
throw new RuntimeException("ERROR on loading inner JAR: " + e.getMessageAll());
}
} // loadJar()
/**
* Using temp files (one per inner JAR/DLL) solves many issues: 1. There are no ways to load JAR
* defined in a JarEntry directly into the JarFile object (see also #6 below). 2. Cannot use
* memory-mapped files because they are using nio channels, which are not supported by JarFile
* ctor. 3. JarFile object keeps opened JAR files handlers for fast access. 4. Deep resource in a
* jar-in-jar does not have well defined URL. Making temp file with JAR solves this problem. 5.
* Similar issues with native libraries: <code>ClassLoader.findLibrary()</code> accepts ONLY
* string with absolute path to the file with native library. 6. Option
* "java.protocol.handler.pkgs" does not allow access to nested JARs(?).
*
* @param inf JAR entry information.
* @return temporary file object presenting JAR entry.
* @throws JarClassLoaderException
*/
private File createTempFile(JarEntryInfo inf) throws JarClassLoaderException {
// Temp files directory:
// WinXP: C:/Documents and Settings/username/Local Settings/Temp/JarClassLoader
// Unix: /var/tmp/JarClassLoader
if (dirTemp == null) {
File dir = new File(System.getProperty("java.io.tmpdir"), TMP_SUB_DIRECTORY);
if (!dir.exists()) {
dir.mkdir();
}
chmod777(dir); // Unix - allow temp directory RW access to all users.
if (!dir.exists() || !dir.isDirectory()) {
throw new JarClassLoaderException("Cannot create temp directory " + dir.getAbsolutePath());
}
dirTemp = dir;
}
File fileTmp = null;
try {
fileTmp = File.createTempFile(inf.getName() + ".", null, dirTemp);
fileTmp.deleteOnExit();
chmod777(fileTmp); // Unix - allow temp file deletion by any user
byte[] a_by = inf.getJarBytes();
BufferedOutputStream os = new BufferedOutputStream(new FileOutputStream(fileTmp));
os.write(a_by);
os.close();
return fileTmp;
} catch (IOException e) {
throw new JarClassLoaderException(
String.format("Cannot create temp file '%s' for %s", fileTmp, inf.jarEntry), e);
}
} // createTempFile()