Bug 137176 It takes unacceptable long time to render a report
Description: Get the attached report design, preview in report designer. It takes unacceptable long time to render a report, and users could not get the output finally. Even during the rending, the computer could not do anything else.
viewer/org.eclipse.birt.report.viewer/birt/WEB-INF/classes/org/eclipse/birt/report/service/ReportEngineService.java
/*************************************************************************************
 * Copyright (c) 2004 Actuate Corporation and others.
 * All rights reserved. This program and the accompanying materials 
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 * 
 * Contributors:
 *     Actuate Corporation - Initial implementation.
 ************************************************************************************/
package org.eclipse.birt.report.service;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.IOException;