Bug 164764 Joint data set does not work properly using attached flatfile
The data set preview keep empty in joint data set. Step to reproduce: 1.Create two data sets based on attached flat file 2.Make an inner join using joint data set with key "A". 3.Preview data set in data set editor. Expect result: The data set preview correctly Actual result: The data set preview is empty.
data/org.eclipse.birt.data/src/org/eclipse/birt/data/engine/script/ScriptEvalUtil.java
}
	}
	
	/**
	 * Evaluates a IJSExpression or IConditionalExpression
	 * 	
	 * @param expr
	 * @param cx
	 * @param scope
	 * @param source
	 * @param lineNo
	 * @return 
	 * @throws DataException
	 */
	public static Object evalExpr( IBaseExpression expr, Context cx, Scriptable scope, 
				String source, int lineNo )
		throws DataException
	{
		if ( logger.isLoggable( Level.FINER ) )
			logger.entering( ScriptEvalUtil.class.getName( ),
				"evalExpr",
				"evalExpr() expr="
						+ LogUtil.toString( expr ) + ", source=" + source
						+ ", lineNo=" + lineNo );
		Object result;
		if ( expr == null )
		{
			result = null;
		}
		else if ( expr instanceof IConditionalExpression)