com.google.appengine.api.datastore
Annotation Type PreQuery
-
@Target(value=METHOD) @Retention(value=RUNTIME) public @interface PreQuery
Identifies a callback method to be invoked before aQuery
for any of the specified kinds is executed against the datastore. Ifkinds()
is not provided the callback will execute for queries against all kinds, including kind-less queries. Methods with this annotation must returnvoid
, must accept a single argument of typePreQueryContext
, 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.
-
-
Optional Element Summary
Optional Elements Modifier and Type Optional Element and Description java.lang.String[]
kinds
The kinds to which this callback applies.
-