package org.briarproject.api.db;

import java.lang.annotation.Retention;
import java.lang.annotation.Target;

import javax.inject.Qualifier;

import static java.lang.annotation.ElementType.FIELD;
import static java.lang.annotation.ElementType.METHOD;
import static java.lang.annotation.ElementType.PARAMETER;
import static java.lang.annotation.RetentionPolicy.RUNTIME;

/**
 * Annotation for injecting the executor for database tasks. Also used for
 * annotating methods that should run on the database executor.
 * <p>
 * The contract of this executor is that tasks are run in the order they're
 * submitted, tasks are not run concurrently, and submitting a task will never
 * block. Tasks must not run indefinitely. Tasks submitted during shutdown are
 * discarded.
 */
@Qualifier
@Target({ FIELD, METHOD, PARAMETER })
@Retention(RUNTIME)
public @interface DatabaseExecutor {}