com.google.cloud.datastore

Class GqlQuery<V>

java.lang.Object

com.google.cloud.datastore.Query<V>

com.google.cloud.datastore.GqlQuery<V>

Type Parameters:

V - the type of the result values this query will produce

All Implemented Interfaces:

RecordQuery<V>, Serializable

public final class GqlQuery<V>
extends Query<V>
implements RecordQuery<V>

A Google Cloud Datastore GQL query.

A usage example:

When the type of the results is known the preferred usage would be:

 Query<Entity> query =
     Query.newGqlQueryBuilder(Query.ResultType.ENTITY, "select * from kind").build();
 QueryResults<Entity> results = datastore.run(query);
 while (results.hasNext()) {
   Entity entity = results.next();
   ...
 }
 

When the type of the results is unknown you can use this approach:

 Query<?> query = Query.newGqlQueryBuilder("select __key__ from kind").build();
 QueryResults<?> results = datastore.run(query);
 if (Key.class.isAssignableFrom(results.getResultClass())) {
   QueryResults<Key> keys = (QueryResults<Key>) results;
   while (keys.hasNext()) {
     Key key = keys.next();
     ...
   }
 }
 

See Also:

GQL Reference, Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	GqlQuery.Builder<V> A GQL query builder.

Nested classes/interfaces inherited from class com.google.cloud.datastore.Query

Query.ResultType<V>

Method Summary

Modifier and Type	Method and Description
boolean	allowLiteral() Returns whether the query string can contain literals.
boolean	equals(Object obj)
Map<String,Object>	getNamedBindings() Returns an immutable map of named bindings.
Map<String,com.google.cloud.datastore.GqlQuery.Binding>	getNamedBindingsMap()
List<Object>	getNumberArgs() Returns an immutable list of positional bindings (using original order).
List<com.google.cloud.datastore.GqlQuery.Binding>	getPositionalBindingsMap()
String	getQueryString() Returns the query string for this query.
Query.ResultType<V>	getType()
int	hashCode()
RecordQuery<V>	nextQuery(RunQueryResponse responsePb)
void	populatePb(RunQueryRequest.Builder requestPb)
String	toString()

Methods inherited from class com.google.cloud.datastore.Query

getNamespace, newAggregationQueryBuilder, newEntityQueryBuilder, newGqlQueryBuilder, newGqlQueryBuilder, newKeyQueryBuilder, newProjectionEntityQueryBuilder

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Method Detail

getQueryString

public String getQueryString()

Returns the query string for this query.

allowLiteral

public boolean allowLiteral()

Returns whether the query string can contain literals. When false, the query string must not contain any literals and instead must bind all values.

getNamedBindings

public Map<String,Object> getNamedBindings()

Returns an immutable map of named bindings.

getNamedBindingsMap

@InternalApi
public Map<String,com.google.cloud.datastore.GqlQuery.Binding> getNamedBindingsMap()

getPositionalBindingsMap

@InternalApi
public List<com.google.cloud.datastore.GqlQuery.Binding> getPositionalBindingsMap()

getNumberArgs

public List<Object> getNumberArgs()

Returns an immutable list of positional bindings (using original order).

getType

public Query.ResultType<V> getType()

Specified by:

getType in interface RecordQuery<V>

toString

public String toString()

Overrides:

toString in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object

equals

public boolean equals(Object obj)

Overrides:

equals in class Object

populatePb

@InternalApi
public void populatePb(RunQueryRequest.Builder requestPb)

Specified by:

populatePb in interface RecordQuery<V>

nextQuery

@InternalApi
public RecordQuery<V> nextQuery(RunQueryResponse responsePb)

Specified by:

nextQuery in interface RecordQuery<V>