Package org.apache.druid.query

Class QueryPlus<T>

  • public final class QueryPlus<T>
extends Object
    An immutable composite object of Query + extra stuff needed in QueryRunners.

    • Method Detail

      • wrap

        public static <T> QueryPlus<T> wrap​(Query<T> query)
        Returns the minimum bare QueryPlus object with the given query. getQueryMetrics() of the QueryPlus object, returned from this factory method, returns null.

      • getQuery

        public Query<T> getQuery()

      • unwrapQuery

        public <C extends Query<T>> C unwrapQuery​(Class<C> clazz)

      • withIdentity

        public QueryPlus<T> withIdentity​(String identity)
        Returns the same QueryPlus object with the identity replaced. This new identity will affect future calls to withoutQueryMetrics() but will not affect any currently-existing queryMetrics.

      • withQueryMetrics

        public QueryPlus<T> withQueryMetrics​(QueryToolChest<T,​? extends Query<T>> queryToolChest)
        Returns the same QueryPlus object, if it already has QueryMetrics (getQueryMetrics() returns not null), or returns a new QueryPlus object with Query from this QueryPlus and QueryMetrics created using the given QueryToolChest, via QueryToolChest.makeMetrics(Query) method. By convention, callers of withQueryMetrics() must also call .getQueryMetrics().emit() on the returned QueryMetrics object, regardless if this object is the same as the object on which .withQueryMetrics() was initially called (i. e. it already had non-null QueryMetrics), or if it is a new QueryPlus object. See MetricsEmittingQueryRunner for example.

      • withoutThreadUnsafeState

        public QueryPlus<T> withoutThreadUnsafeState()
        Returns a QueryPlus object without the components which are unsafe for concurrent use from multiple threads, therefore couldn't be passed down in concurrent or async QueryRunners. Currently the only unsafe component is QueryMetrics, i. e. withoutThreadUnsafeState() call is equivalent to withoutQueryMetrics().

      • withMaxQueuedBytes

        public QueryPlus<T> withMaxQueuedBytes​(long maxQueuedBytes)
        Equivalent of withQuery(getQuery().withOverriddenContext(ImmutableMap.of(MAX_QUEUED_BYTES_KEY, maxQueuedBytes))).

      • withQuery

        public <U> QueryPlus<U> withQuery​(Query<U> replacementQuery)
        Returns a QueryPlus object with QueryMetrics from this QueryPlus object, and the provided Query.