org.eiichiro.acidhouse

Interface Update<E>

All Superinterfaces:

Command<Integer>

public interface Update<E>
extends Command<Integer>

Update is a command interface to update properties of Session entity matches to the specified Filters with the specified value in Acid House's transactional session. This command execution returns the count of updated entities. You can build & execute this command as the following code:

 import org.eiichiro.acidhouse.Session;
 import org.eiichiro.acidhouse.appengine.AppEngineDatastoreSession;
 ...
 
 Session session = new AppEngineDatastoreSession();
 Transaction transaction = session.beginTransaction();
 
 try {
        session.update(Entity3.class)
                        .set(entity3$.i, 100)
                        .set(entity3$.entity1.i, new Modification<Integer>() {
 
                                public Integer apply(Integer from) {
                                        return from + 10;
                                }
 
                        })
                        .filter(entity3$.id.equalTo("Key1"))
                        .execute();
        transaction.commit();
 } catch (Exception e) {
        transaction.rollback();
        throw e;
 } finally {
        session.close();
 }
 

Author:

Eiichiro Uchiumi

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static interface	Update.Modification<T> Modification function applied to the property to be updated.

Method Summary

Methods

Modifier and Type	Method and Description
Update<E>	filter(Filter<?>... filters) Qualifies entities to be updated with the specified Filters.
<T> Update<E>	set(Property<?,T> property, T value) Qualifies property and the value to be updated.
<T> Update<E>	set(Property<?,T> property, Update.Modification<T> modification) Qualifies property to be updated and the modification function.

Methods inherited from interface org.eiichiro.acidhouse.Command

execute

Method Detail

set

<T> Update<E> set(Property<?,T> property,
                T value)

Qualifies property and the value to be updated.

Parameters:

property - The property to be updated by this Update.

value - The property value to be updated to.

Returns:

The Update to update the specified entity properties.

set

<T> Update<E> set(Property<?,T> property,
                Update.Modification<T> modification)

Qualifies property to be updated and the modification function.

Parameters:

property - The property to be updated by this Update.

modification - The modification function applied to the property.

Returns:

The Update to update the specified entity properties.

filter

Update<E> filter(Filter<?>... filters)

Qualifies entities to be updated with the specified Filters. Each of the specified filters is combined with "logical and".

Parameters:

filters - Filters to qualify entities to be updated.

Returns:

The Update to update entities qualified with the specified Filters.