com.sleepycat.je.trigger.PersistentTrigger Maven / Gradle / Ivy
/*-
* Copyright (C) 2002, 2018, Oracle and/or its affiliates. All rights reserved.
*
* This file was distributed by Oracle as part of a version of Oracle Berkeley
* DB Java Edition made available at:
*
* http://www.oracle.com/technetwork/database/database-technologies/berkeleydb/downloads/index.html
*
* Please see the LICENSE file included in the top-level directory of the
* appropriate version of Oracle Berkeley DB Java Edition for a copy of the
* license and additional information.
*/
package com.sleepycat.je.trigger;
import java.io.Serializable;
import com.sleepycat.je.Database;
import com.sleepycat.je.Environment;
import com.sleepycat.je.Transaction;
/**
* Placeholder to be used when persistent triggers are supported in the future.
* See warning at the top of Trigger.java
*
* Note that all subtypes of PersistentTrigger must be serializable, because
* they are stored persistently in the environment.
*
* The following table captures the relationship between the database
* granularity operations and their associated trigger methods.
*
*
*
* Database Operation
* Trigger Method
*
*
* {@link Environment#openDatabase Environment.openDatabase} resulting in
* the creation of a new primary database. Or the first open of a database for
* write operations.
* {@link #open open}
*
*
* {@link Database#close Database.close} the close of a database that was
* opened for write operations.
* {@link #close close}
*
*
* {@link Environment#removeDatabase Environment.removeDatabase}
* {@link PersistentTrigger#remove remove}
*
*
* {@link Environment#truncateDatabase Environment.truncateDatabase}
* {@link PersistentTrigger#truncate truncate}
*
*
* {@link Environment#renameDatabase Environment.renameDatabase}
* {@link PersistentTrigger#rename rename}
*
*
*/
public interface PersistentTrigger extends Trigger, Serializable {
/* Database operations */
/**
* The trigger method invoked after the open of the first {@link Database}
* writable handle.
*
* A call to the open trigger always precedes any subsequent calls to the
* {@link #put} and {@link #delete} triggers defined below, since the
* put and delete operations can only be invoked
* on a database handle.
*
* If the database is replicated, the replay mechanism on a
* Replica may open and close databases as it replays the
* replication stream. The maximum number of databases that may be open at
* any given time and the duration for which they can be left open can be
* controlled by configuring
* ReplicationConfig.REPLAY_MAX_OPEN_DB_HANDLES and
* ReplicationConfig.REPLAY_DB_HANDLE_TIMEOUT respectively.
*
* The method may be invoked when the database is first created, or
* subsequently when a new trigger is added to an existing database. As a
* result, a call to this trigger is always preceded by a call to the
* {@link #addTrigger(Transaction) addTrigger} trigger method.
*
* @param txn the active transaction associated with the operation. The
* argument is null if the operation is not transactional.
*
* @param environment a handle to the environment associated with the
* database being opened. The trigger code must not close the environment
* handle.
*
* @param isNew is true if the database was newly created as a result of
* the call to {@link Environment#openDatabase}
*
* @see Environment#openDatabase
*/
public void open(Transaction txn, Environment environment, boolean isNew);
/**
* The trigger method associated with the close of the last writable
* {@link Database} handle.
*
* If the database is replicated, the replay mechanism on a
* Replica may open and close databases as it replays the
* replication stream. The maximum number of databases that may be open at
* any given time and the duration for which they can be left open can be
* controlled by configuring
* ReplicationConfig.REPLAY_MAX_OPEN_DB_HANDLES and
* ReplicationConfig.REPLAY_DB_HANDLE_TIMEOUT respectively.
*
* @see Database#close
*/
public void close();
/**
* The trigger method invoked after the successful removal of a primary
* {@link Database}.
*
* @param txn the transaction associated with the operation. The argument
* is null if the environment is non-transactional.
*
* @see Environment#removeDatabase
*/
public void remove(Transaction txn);
/**
* The trigger method invoked after the successful truncation of a
* {@link Database}.
*
* @param txn the transaction associated with the operation. The argument
* is null if the environment is non-transactional.
*
* @see Environment#truncateDatabase
*/
public void truncate(Transaction txn);
/**
* The trigger method invoked after the successful renaming of a primary
* {@link Database}.
*
* @param txn the transaction associated with the operation. The argument
* is null if the environment is non-transactional.
*
* @param newName it's current (new) name
*
* @see Environment#renameDatabase
*/
public void rename(Transaction txn, String newName);
}