Bug 179636 [Smoke] Chart can not be previewed [0001]
Description: Chart can not be previewed Build number: 2.2.0.v20070328-0630 Steps to reproduce: 1. New a chart, preview. Expected result: Chart is displayed correctly. Actual result: Chart can not be previewed. Error log: N/A
viewer/org.eclipse.birt.report.viewer/birt/WEB-INF/classes/org/eclipse/birt/report/utility/ParameterAccessor.java
}
	/**
	 * Clears the report document/image files which had been created last time
	 * the server starts up.
	 */
	protected static void clearTempFiles( )
	{
		
		File file = new File( documentFolder );
		deleteDir( file );
		makeDir( documentFolder );
		
		file = new File( imageFolder );
		deleteDir( file );
		makeDir( imageFolder );
	}
	/**
	 * Deletes all files and subdirectories under dir. Returns true if all
	 * deletions were successful. If a deletion fails, the method stops
	 * attempting to delete and returns false.
	 */
	protected static boolean deleteDir( File dir )
	{
		if ( dir.isDirectory( ) )
		{
			String[] children = dir.list( );
			for ( int i = 0; i < children.length; i++ )
			{
				boolean success = deleteDir( new File( dir, children[i] ) );
				if ( !success )