@Override
    public OutputStream.OutputEventType visitOutput_event_type(@NotNull SiddhiQLParser.Output_event_typeContext ctx) {
//        output_event_type
//        : ALL EVENTS | EXPIRED EVENTS | CURRENT? EVENTS
//        ;

        if (ctx.ALL() != null) {
            return OutputStream.OutputEventType.ALL_EVENTS;
        } else if (ctx.EXPIRED() != null) {
            return OutputStream.OutputEventType.EXPIRED_EVENTS;
        } else {
            return OutputStream.OutputEventType.CURRENT_EVENTS;
        }
    }
{@inheritDoc}
<p>The default implementation returns the result of calling
{@link #visitChildren} on {@code ctx}.</p>

@param ctx
modules/siddhi-query-compiler/src/main/java/io/siddhi/query/compiler/internal/SiddhiQLBaseVisitorImpl.java