com.googlecode.objectify.cmd

Interface QueryExecute<T>

All Superinterfaces:

Iterable<T>, QueryResultIterable<T>

All Known Subinterfaces:

Loader, LoadType<T>, Query<T>, QueryKeys<T>, SimpleQuery<T>

All Known Implementing Classes:

QueryImpl, SimpleQueryImpl

public interface QueryExecute<T>
extends QueryResultIterable<T>

Most of the various methods that can end the definition of a query and start execution. The first() method is excluded because it returns a Ref which encapsulates both the regular and keys-only result. It makes no sense to have a Ref>, but when you do keys() you get a QueryExecute>.

Author:

Jeff Schnitzer

Method Summary

Modifier and Type	Method and Description
LoadResult<T>	first() Gets the first entity in the result set.
QueryResultIterable<T>	iterable() Starts an asynchronous query which will return entities.
List<T>	list() Execute the query and get the results as a List.
String	toString() Generates a string that consistently and uniquely specifies this query.

Methods inherited from interface com.googlecode.objectify.cmd.QueryResultIterable

iterator

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Method Detail

iterable

QueryResultIterable<T> iterable()

Starts an asynchronous query which will return entities.

Note that since the Query itself is QueryResultIterable, you can iterate on the query object itself. However, if you want to start an async query and iterate on it later, you can use this method.

list

List<T> list()

Execute the query and get the results as a List. The list will be equivalent to a simple ArrayList; you can iterate through it multiple times without incurring additional datastore cost.

Note that you must be careful about limit()ing the size of the list returned; you can easily exceed the practical memory limits of Appengine by querying for a very large dataset.

first

LoadResult<T> first()

Gets the first entity in the result set. Obeys the offset value.

Returns:

an asynchronous result containing the first result. The result will hold null if the result set is empty.

toString

String toString()

Generates a string that consistently and uniquely specifies this query. There is no way to convert this string back into a query and there is no guarantee that the string will be consistent across versions of Objectify.

In particular, this value is useful as a key for a simple memcache query cache.

Overrides:

toString in class Object