/* * Copyright (C) 2017 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package android.arch.persistence.room; import java.lang.annotation.ElementType; import java.lang.annotation.Retention; import java.lang.annotation.RetentionPolicy; import java.lang.annotation.Target; /** * Marks a method in an abstract {@link Dao} class as a transaction method. *
* The derived implementation of the method will execute the super method in a database transaction. * All the parameters and return types are preserved. The transaction will be marked as successful * unless an exception is thrown in the method body. *
* Example: *
* {@literal @}Dao * public abstract class ProductDao { * {@literal @}Insert * public abstract void insert(Product product); * {@literal @}Delete * public abstract void delete(Product product); * {@literal @}Transaction * public void insertAndDeleteInTransaction(Product newProduct, Product oldProduct) { * // Anything inside this method runs in a single transaction. * insert(newProduct); * delete(oldProduct); * } * } **/ @Target({ElementType.METHOD}) @Retention(RetentionPolicy.CLASS) public @interface Transaction { }