if ( tempRootDirStr != null )
if ( tempRootDirStr != null && new File( tempRootDirStr ).exists( ) == true )
		private void createTempRootDir( )		{			if ( tempRootDirStr != null )				return;						// system default temp dir is used			String tempDirStr = System.getProperty( "java.io.tmpdir" );			File tempDtEDir = new File( tempDirStr, "BirtDataCache" );			if ( tempDtEDir.exists( ) == false )			{				tempDtEDir.mkdir( );			}			else			{				File[] sessionsFolder = tempDtEDir.listFiles( );				for ( int i = 0; i < sessionsFolder.length; i++ )				{					File[] oneSessionFolder = sessionsFolder[i].listFiles( );					for ( int j = 0; j < oneSessionFolder.length; j++ )					{						// temp files						if ( oneSessionFolder[j].isDirectory( ) )						{							File[] oneSessionTempFiles = oneSessionFolder[j].listFiles( );							for ( int k = 0; k < oneSessionTempFiles.length; k++ )							{								oneSessionTempFiles[k].delete( );							}							oneSessionFolder[j].delete( );						}						// goal file						else						{							oneSessionFolder[j].delete( );						}					}					sessionsFolder[i].delete( );				}			}			try			{				tempRootDirStr = tempDtEDir.getCanonicalPath( );			}			catch ( IOException e )			{				// normally this exception will never be thrown			}		}