org.eclipse.persistence.sequencing.SequencingControl Maven / Gradle / Ivy
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/*
* Copyright (c) 1998, 2019 Oracle and/or its affiliates. All rights reserved.
*
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License v. 2.0 which is available at
* http://www.eclipse.org/legal/epl-2.0,
* or the Eclipse Distribution License v. 1.0 which is available at
* http://www.eclipse.org/org/documents/edl-v10.php.
*
* SPDX-License-Identifier: EPL-2.0 OR BSD-3-Clause
*/
// Contributors:
// Oracle - initial API and implementation from Oracle TopLink
package org.eclipse.persistence.sequencing;
import org.eclipse.persistence.sessions.Login;
import org.eclipse.persistence.sessions.server.ConnectionPool;
/**
*
* Purpose: Define an interface to control sequencing functionality.
*
* Description: This interface is accessed through DatabaseSession.getSequencingControl().
* It allows to create, re-create, customize Sequencing object
* which is available through DatabaseSession.getSequencing()
* and provides sequencing values for all descriptors that use sequencing.
*
* Here's the lifecycle of Sequencing object used by DatabaseSession:
* 1. DatabaseSession created - sequencing object doesn't yet exist;
* 2. DatabaseSession.login() causes creation of Sequencing object;
* 3. DatabaseSession.logout() causes destruction of Sequencing object.
*
* In case sequencing object doesn't yet exist all the set parameters' values will be used
* during its creation.
*
* In case sequencing object already exists:
* 1. The following methods don't alter sequencing object - the corresponding parameters will only
* be used in case a new sequencing object is created:
* setShouldUseSeparateConnection;
* setLogin;
* setMinPoolSize;
* setMaxPoolSize.
* 2. The following methods cause immediate destruction of the sequencing object and creation of a new one:
* setValueGenerationPolicy;
* setShouldUseNativeSequencing;
* setShouldUseTableSequencing;
* resetSequencing;
* 3. The following methods cause change immediately:
* setPreallocationSize (next sequencing preallocation will use the set parameter's value).
*
* Responsibilities:
*
* - Define the APIs for controlling sequencing.
*
* @see Sequence
* @see org.eclipse.persistence.sessions.DatabaseSession
*/
public interface SequencingControl {
/**
* ADVANCED:
* Immediately re-create sequencing object.
* The only reason to use this method is to pick up all parameters'
* values that were changed after the original sequencing object has been created.
*/
void resetSequencing();
/**
* PUBLIC:
* Indicate whether separate connection(s) for sequencing could be used
* (by default it couldn't).
* If this flag is set to true then separate connection(s) for sequencing
* will be used in case getSequence().shouldUseSeparateConnection()
* returns true.
* @see Sequence
*/
boolean shouldUseSeparateConnection();
/**
* PUBLIC:
* Set whether separate connection(s) for sequencing could be used
* (by default it couldn't).
* If this flag is set to true then separate connection(s) for sequencing
* will be used in case getSequence().shouldUseSeparateConnection()
* returns true.
* @see Sequence
*/
void setShouldUseSeparateConnection(boolean shouldUseSeparateConnection);
/**
* PUBLIC:
* Indicates whether sequencing actually uses separate connection(s).
* Returns true if sequencing is connected and uses separate connection(s).
* Returns false if sequencing is not connected (getSequencing()==null).
* Note that if shouldUseSeparateConnection() returns false this method also returns false.
* However if shouldUseSeparateConnection() returns true this method
* returns false in the following two cases:
*
sequencing is not connected;
*
getSequence().shouldUseSeparateConnection() == false.
* @see Sequence
*/
boolean isConnectedUsingSeparateConnection();
/**
* ADVANCED:
* Return a DatabaseLogin to be used by separate sequencing connection(s).
* @see org.eclipse.persistence.sessions.DatabaseLogin
*/
Login getLogin();
/**
* ADVANCED:
* Returns a DatabaseLogin to be used by separate sequencing connection(s)
* The set value is ignored if shouldUseSeparateConnection() returns false.
* The DatabaseLogin *MUST*:
* 1. specify *NON-JTS* connections (such as NON_JTS driver or read-only datasource);
* 2. sequenceLogin.shouldUseExternalTransactionController()==false
* In case this method is not called, but separate connection should be used,
* sequencing will use a clone of login owned by the DatabaseSession,
* or a clone of read login owned by ServerSession.
* @see org.eclipse.persistence.sessions.DatabaseLogin
*/
void setLogin(Login login);
/**
* ADVANCED:
* Return the connection pool to use for sequencing.
*/
ConnectionPool getConnectionPool();
/**
* ADVANCED:
* Set the connection pool to use for sequencing.
*/
void setConnectionPool(ConnectionPool pool);
/**
* PUBLIC:
* Returns a minimum number of connections in sequencing connection pool.
* @see org.eclipse.persistence.sessions.server.ConnectionPool
* @see org.eclipse.persistence.sessions.server.ServerSession
*/
int getMinPoolSize();
/**
* PUBLIC:
* Sets a minimum number of connections in sequencing connection pool
* The set value is ignored if shouldUseSeparateConnection() returns false.
* The set value is ignored if SequencingControl has been obtained not from ServerSession.
* By default is 2.
* @see org.eclipse.persistence.sessions.server.ConnectionPool
* @see org.eclipse.persistence.sessions.server.ServerSession
*/
void setMinPoolSize(int size);
/**
* PUBLIC:
* Returns a maximum number of connections in sequencing connection pool
* @see org.eclipse.persistence.sessions.server.ConnectionPool
* @see org.eclipse.persistence.sessions.server.ServerSession
*/
int getMaxPoolSize();
/**
* PUBLIC:
* Sets a maximum number of connections in sequencing connection pool
* The set value is ignored if shouldUseSeparateConnection() returns false.
* The set value is ignored if SequencingControl has been obtained not from ServerSession.
* By default is 2.
* @see org.eclipse.persistence.sessions.server.ConnectionPool
* @see org.eclipse.persistence.sessions.server.ServerSession
*/
void setMaxPoolSize(int size);
/**
* PUBLIC:
* Sets a initial number of connections in sequencing connection pool
* The set value is ignored if shouldUseSeparateConnection() returns false.
* The set value is ignored if SequencingControl has been obtained not from ServerSession.
* By default is 1.
* @see org.eclipse.persistence.sessions.server.ConnectionPool
* @see org.eclipse.persistence.sessions.server.ServerSession
*/
void setInitialPoolSize(int size);
/**
* ADVANCED:
* Removes all preallocated sequencing objects.
* Ignored if getSequencingValueGenarationPolicy().shouldUsePreallocation() returns false.
* This method is called internally after Sequencing object is destructed.
* @see Sequence
*/
void initializePreallocated();
/**
* ADVANCED:
* Removes all preallocated sequencing objects for the given sequence name.
* Ignored if getSequencingValueGenarationPolicy().shouldUsePreallocation() returns false.
* @see Sequence
*/
void initializePreallocated(String seqName);
}