org.apache.druid.query

Class QueryPlus<T>

java.lang.Object

org.apache.druid.query.QueryPlus<T>

public final class QueryPlus<T>
extends Object

An immutable composite object of Query + extra stuff needed in QueryRunners.

Method Summary

Modifier and Type	Method and Description
Query<T>	getQuery()
QueryMetrics<?>	getQueryMetrics()
QueryPlus<T>	optimizeForSegment(PerSegmentQueryOptimizationContext optimizationContext)
Sequence<T>	run(QuerySegmentWalker walker, ResponseContext context)
QueryPlus<T>	withIdentity(String identity) Returns the same QueryPlus object with the identity replaced.
QueryPlus<T>	withMaxQueuedBytes(long maxQueuedBytes) Equivalent of withQuery(getQuery().withOverriddenContext(ImmutableMap.of(MAX_QUEUED_BYTES_KEY, maxQueuedBytes))).
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.
<U> QueryPlus<U>	withQuery(Query<U> replacementQuery) Returns a QueryPlus object with QueryMetrics from this QueryPlus object, and the provided Query.
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.
static <T> QueryPlus<T>	wrap(Query<T> query) Returns the minimum bare QueryPlus object with the given query.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

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()

getQueryMetrics

@Nullable
public QueryMetrics<?> getQueryMetrics()

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.

run

public Sequence<T> run(QuerySegmentWalker walker,
                       ResponseContext context)

optimizeForSegment

public QueryPlus<T> optimizeForSegment(PerSegmentQueryOptimizationContext optimizationContext)