Identifies a callback method to be invoked before a Query for any of the specified kinds
is executed against the datastore. If #kinds() is not provided the callback will execute
for queries against all kinds, including kind-less queries. Methods with this annotation must
return void, must accept a single argument of type PreQueryContext, must not
throw any checked exceptions, must not be static, and must belong to a class with a no-arg
constructor. Neither the method nor the no-arg constructor of the class to which it belongs are
required to be public. Methods with this annotation are free to throw any unchecked exception
they like. Throwing an unchecked exception will prevent callbacks that have not yet been executed
from running, and the exception will propagate to the code that invoked the datastore operation
that resulted in the invocation of the callback. Throwing an unchecked exception from a callback
will prevent the datastore operation from executing.
[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Hard to understand","hardToUnderstand","thumb-down"],["Incorrect information or sample code","incorrectInformationOrSampleCode","thumb-down"],["Missing the information/samples I need","missingTheInformationSamplesINeed","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-03-05 UTC."],[[["`PreQuery` is an interface annotation that designates a callback method to be executed before a `Query` is run against the datastore for specified kinds."],["Callback methods annotated with `PreQuery` must be `void`, accept a single `PreQueryContext` argument, cannot throw checked exceptions, and must be non-static within a class having a no-argument constructor."],["The `kinds()` method within `PreQuery` specifies the datastore kinds to which the callback applies, with an empty array default indicating all kinds."],["If a callback throws an unchecked exception, it halts subsequent callbacks and prevents the datastore operation, propagating the exception to the invoking code."]]],[]]
