PreGetContext (Google App Engine API for Java)

Class PreGetContext

  • java.lang.Object
  • All Implemented Interfaces:

    public final class PreGetContext
    extends java.lang.Object
    Concrete CallbackContext implementation that is specific to intercepted get() operations. Methods annotated with PreGet that receive instances of this class may modify the result of the get() operation by calling setResultForCurrentElement(Entity). Keys that receive results via this method will not be fetched from the datastore. This is an effective way to inject cached results.
    • Method Detail

      • setResultForCurrentElement

        public void setResultForCurrentElement(Entity entity)
        Set the Entity that will be associated with the Key returned by getCurrentElement() in the result of the get() operation. This will prevent the get() operation from fetching the Entity from the datastore. This is an effective way to inject cached results.
        entity - The entity to provide as the result for the current element.
        java.lang.IllegalArgumentException - If the key of the provided entity is not equal to the key returned by getCurrentElement().
      • getElements

        public java.util.List<T> getElements()
        Specified by:
        getElements in interface CallbackContext<T>
        An unmodifiable view of the elements involved in the operation that triggered the callback..
      • getCurrentElement

        public T getCurrentElement()
        Specified by:
        getCurrentElement in interface CallbackContext<T>
        The element for which the callback has been invoked. Shortcut for getElements().getCurrentIndex().
      • toString

        public java.lang.String toString()
        toString in class java.lang.Object