Bug 211004 Failed to remove temp db directory after running multiple reports
Description: I use Report Engine API to do runAndrender, run and dataextract tasks on multiple reports. Before the Platform started, I change the temp folder(System.setProperty( "java.io.tmpdir", TEMP_HOME )). Each task is closed after it finished and I shutdown the Platform after all the tasks finished. In log I found "Fail to remove one or more file in temp db directory,but it will be removed when the VM exits: D:\BIRT_NG\temp/BIRTSampleDB_1196129572031_10a6ae2". In temp folder the BIRTSampleDB_XXX is still here but not removed. I think it is the issue when remove the Temp sampleDB. Build number: 2.3.0.v20071127-0630
data/org.eclipse.birt.report.data.oda.jdbc/src/org/eclipse/birt/report/data/oda/jdbc/JDBCDriverManager.java
if(  refreshUrlsWhenFail && extraDriverLoader.refreshURLs() )
			{
				
				return loadExtraDriver( className, false, driverClassPath );
			}
			
			
			logger.log( Level.FINER, "Driver class not found in drivers directory: " + className );
			return null;
		}
	}
	
	private static class DriverClassLoader extends URLClassLoader
	{
		private Bundle bundle;
		private HashSet fileSet = new HashSet();
		private String driverClassPath;
		public DriverClassLoader( String driverClassPath ) throws OdaException 
		{
			super( new URL[0], DriverClassLoader.class.getClassLoader() );
			logger.entering( DriverClassLoader.class.getName(), "constructor()" );
			this.driverClassPath = driverClassPath;
			bundle = Platform.getBundle( "org.eclipse.birt.report.data.oda.jdbc" );
			if ( bundle == null )
			{
				
				logger.severe( "Failed to get Bundle object" );
			}
			else
			{