Bug 214204 Only document content in document folder should be removed.[0601]
Description: Only document related content in document folder should be removed. Build number:2.3.0.v20080103 Steps to reproduce: 1. Deploy BIRT. 2. Edit web.xml to set BIRT_VIEWER_DOCUMENT_FOLDER to your local path and there are content inside the path. 3. Start server and click View Example to preview sample report. Expected result: Only content created by viewer should be removed in specified document folder. Actual result: All contents are deleted despite whether they are related with BIRT. Error log:n/a
viewer/org.eclipse.birt.report.viewer/birt/WEB-INF/classes/org/eclipse/birt/report/utility/ParameterAccessor.java
* @return
	 */
	public static boolean isOverwrite( HttpServletRequest request )
	{
		boolean overwrite = isOverWrite;
		String urlParam = getParameter( request, PARAM_OVERWRITE );
		if ( "true".equalsIgnoreCase( urlParam ) ) 
		{
			overwrite = true;
		}
		else if ( "false".equalsIgnoreCase( urlParam ) ) 
		{
			overwrite = false;
		}
		return overwrite;
	}
	/**
	 * Checks if a given file name is a relative path.
	 * 
	 * @param fileName
	 *            The file name.
	 * @return A <code>boolean</code> value indicating if the file name is a
	 *         relative path or not.
	 */
	public static boolean isRelativePath( String fileName )
	{
		if ( fileName == null )
		{
			return false;
		}