Locker_JavaNio.lock() doesn't wrap I/O exceptions

[trancexpress]

We have this exception printed on standard error:

Caused by: java.io.IOException: An error occurred while locking file "...": "No locks available". A common reason is that the file system or Runtime Environment does not support file locking for that location. Please choose a different location, or disable file locking by passing "-Dosgi.locking=none" as a VM argument.
	at org.eclipse.osgi.internal.location.Locker_JavaNio.lock(Locker_JavaNio.java:53)
	at org.eclipse.osgi.storagemanager.StorageManager.lock(StorageManager.java:403)
	at org.eclipse.osgi.storagemanager.StorageManager.open(StorageManager.java:716)
	at org.eclipse.osgi.storage.Storage.getChildStorageManager(Storage.java:2241)
	at org.eclipse.osgi.storage.Storage.getInfoInputStream(Storage.java:2258)
	at org.eclipse.osgi.storage.Storage.<init>(Storage.java:253)
	at org.eclipse.osgi.storage.Storage.createStorage(Storage.java:181)
	at org.eclipse.osgi.internal.framework.EquinoxContainer.<init>(EquinoxContainer.java:108)

While the error message tries to explain what went wrong, I would still like to know what the actual occurred IOException is. It should get wrapped, not just used to extend the error message:

	@Override
	public synchronized boolean lock() throws IOException {
		raFile = new RandomAccessFile(lockFile, "rw"); //$NON-NLS-1$
		try {
			/*
			 * fix for bug http://bugs.sun.com/view_bug.do?bug_id=6628575 and
			 * https://bugs.eclipse.org/bugs/show_bug.cgi?id=44735#c17
			 */
			fileLock = raFile.getChannel().tryLock(0, 1, false);
		} catch (IOException ioe) {
			// print exception if debugging
			if (debug)
				System.out.println(NLS.bind(Msg.location_cannotLock, lockFile));
			// produce a more specific message for clients
			String specificMessage = NLS.bind(Msg.location_cannotLockNIO, new Object[] {lockFile, ioe.getMessage(), "\"-D" + LocationHelper.PROP_OSGI_LOCKING + "=none\""}); //$NON-NLS-1$ //$NON-NLS-2$
			throw new IOException(specificMessage);
		} catch (OverlappingFileLockException e) {
			// handle it as null result
			fileLock = null;
		} finally {
			if (fileLock != null)
				return true;
			raFile.close();
			raFile = null;
		}
		return false;
	}

I essentially have to grep OpenJDK code to find where "No locks available" is coming from.

[tjwatson]

I agree, we should set the cause of the thrown new IOException with the original one caught.