Bug 165188 logging per report
Setting up a dedicated (birt) report server, which serves all our web apps, leads to a logging desaster. Birtegine logs all messages to one file. There's no info which rptdesign caused the logmessage or who (e.g. user) caused the logmessage. Retrieving who/which rpt caused some logmessage is not possible! There are two possible solutions: (a) prefixing each logmessage with a userdefineable message (task.setLogprefix("myprefix")) (b) set an outputstream for each task (task.setLoggingOutputStream(outputstream)) to split the huge logfile to many small pieces.
engine/org.eclipse.birt.report.engine/src/org/eclipse/birt/report/engine/api/impl/EngineTask.java
}
				boolean visitParameterGroup( ParameterGroupHandle group,
						Object value )
				{
					return visitParametersInGroup( group, value );
				}
			}.visit( (ReportDesignHandle) runnable.getDesignHandle( ), null );
			log.log( Level.FINE, "Running the report with paramters: {0}",
					buffer );
		}
	}
	/**
	 * validate whether the parameter value is a valid value for the parameter
	 * 
	 * @param p
	 *            the parameter to be verified
	 * @param paramValue
	 *            the value for the parameter
	 * @return true if the given parameter value is valid; false otherwise
	 */
	private boolean validateScalarParameter( ScalarParameterHandle paramHandle )
	{
		String paramName = paramHandle.getName( );
		Object paramValue = runValues.get( paramName );
		String type = paramHandle.getDataType( );
		
		if ( paramValue == null )
		{
			if ( !paramHandle.isRequired( ) )
				return true;