public Event[] query(String onDemandQuery) {
        if (this.running) {
            return query(SiddhiCompiler.parseOnDemandQuery(onDemandQuery), onDemandQuery);
        }
        throw new OnDemandQueryCreationException("The siddhi app, '" + this.getName() + "' is currently shut down, " +
                "the on demand query '" + onDemandQuery + "' cannot be executed.");
    }
Get the names of the available queries.

@return string set of query names.
modules/siddhi-core/src/main/java/io/siddhi/core/SiddhiAppRuntimeImpl.java